FM250G
Broadcast Transmitter
User’s Manual
©2002 Crown Broadcast, a division of International Radio and Electronics, Inc.
25166 Leer Drive, Elkhart, Indiana, 46514-5425 U.S.A.
(574) 262-8900
Revision Control
Revision
Print Date
Rev A
September 2002
Important Notices
©2002 International Radio and Electronics, Inc.
Portions of this document were originally copyrighted by Michael P. Axman in 1991.
All rights reserved. No part of this publication may be reproduced, transmitted,
transcribed, stored in a retrieval system, or translated into any language in any form
by any means without the written permission of Crown International, Inc.
Printed in U.S.A.
Sony and RCA are trademarks of their respective companies.
IREC attempts to provide information that is accurate, complete, and useful.
Should you find inadequacies in the text, please send your comments to the
following address:
International Radio and Electronics
25166 Leer Drive, P.O. Box 2000
Elkhart, Indiana, 46515-2000 U.S.A.
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FM250G User’s Manual
Rev A
Table of Contents
Section 1—Getting Acquainted
1.1 Your Transmitter ........................................................................................ 1–2
1.2 Applications and Options ............................................................................ 1–3
1.2.1 Stand-Alone............................................................................................ 1–4
1.2.2 Backup ................................................................................................... 1–4
1.2.3 Booster................................................................................................... 1–4
1.2.4 Exciter .................................................................................................... 1–4
1.2.5 Translator............................................................................................... 1–5
1.2.6 Satellator ................................................................................................ 1–6
1.2.7 Nearcasting ............................................................................................ 1–6
1.3 Transmitter/Exciter Specifications .............................................................. 1–7
1.4 Receiver Specifications............................................................................... 1–8
1.5 Safety Considerations ................................................................................. 1–9
1.5.1 Dangers.................................................................................................. 1–9
1.5.2 Warnings................................................................................................ 1–9
1.5.3 Cautions ................................................................................................. 1–9
Section 2—Installation
2.1 Operating Location ......................................................................................2-2
2.2 Power Connections......................................................................................2-2
2.3 Frequency (Channel) Selection ....................................................................2-4
2.3.1 Modulation Compensator ........................................................................2-5
2.3.2 RF Tuning Adjustments ...........................................................................2-5
2.4 Receiver Frequency Selection ......................................................................2-6
2.5 RF Connections ...........................................................................................2-8
2.6 Audio Input Connections .............................................................................2-9
2.7 SCA Input Connections..............................................................................2-10
2.8 Composite Input Connection .....................................................................2-10
2.9 Audio Monitor Connections .......................................................................2-11
2.10 Pre-emphasis Selection .............................................................................2-11
2.11 Processor Bypass Option ..........................................................................2-11
2.12 Program Input Fault Time-out ...................................................................2-12
2.13 Remote I/O Connector ...............................................................................2-12
Section 3—Operation
3.1 FM250G Initial Power-up Procedures ......................................................... 3–2
3.1.1 Power Switch ......................................................................................... 3–3
3.1.2 Carrier Switch......................................................................................... 3–3
3.2 Front Panel Bar-Dot Displays...................................................................... 3–4
3.2.1 Audio Processor Input............................................................................ 3–4
3.2.2 Highband and Wideband Display............................................................ 3–4
3.2.3 Modulation Display................................................................................. 3–4
3.3 Input Gain Switches.................................................................................... 3–5
3.4 Processing Control ..................................................................................... 3–5
3.5 Stereo-Mono Switch ................................................................................... 3–5
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3.6 RF Output Control....................................................................................... 3–6
3.7 Digital Multimeter ....................................................................................... 3–6
3.8 Fault Indicators ........................................................................................... 3–7
Section 4—Principles of Operation
4.1
4.2
4.3
4.4
4.5
4.6
4.7
4.8
4.9
4.10
4.11
4.12
4.13
4.14
Part Numbering .......................................................................................... 4–2
Audio Processor Circuit Board.................................................................... 4–2
Stereo Generator Circuit Board ................................................................... 4–4
RF Exciter Circuit Board.............................................................................. 4–5
Metering Circuit Board................................................................................ 4–6
Motherboard............................................................................................... 4–8
Display Circuit Board .................................................................................. 4–8
Voltage Regulator Circuit Board.................................................................. 4–9
Power Regulator Circuit Board ................................................................. 4–10
RF Driver .................................................................................................. 4–11
RF Amplifier.............................................................................................. 4–11
Chassis and AC Supply............................................................................. 4–11
RF Output Filter & Reflectometer .............................................................. 4–12
Receiver Circuit Board Option................................................................... 4–12
Section 5—Adjustments and Tests
5.1 Audio Processor Adjustments .................................................................... 5–2
5.1.1 Pre-Emphasis Selection ......................................................................... 5–2
5.1.2 Pre-Emphasis Fine Adjustment .............................................................. 5–2
5.2 Stereo Generator Adjustments.................................................................... 5–2
5.2.1 Separation .............................................................................................. 5–2
5.2.2 Composite Output .................................................................................. 5–2
5.2.2.1
Using a Modulation Monitor ............................................................ 5–2
5.2.2.2
Using Bessel Nulls ........................................................................... 5–3
5.2.3 19–kHz Level.......................................................................................... 5–3
5.2.4 19–kHz Phase......................................................................................... 5–3
5.3 Frequency Synthesizer Adjustments ........................................................... 5–3
5.3.1 Frequency Channel Selections................................................................ 5–3
5.3.2 Modulation Compensator ....................................................................... 5–4
5.3.3 Frequency Measurement and Adjustment .............................................. 5–4
5.3.4 FSK Balance Control............................................................................... 5–4
5.4 Metering Board Adjustments ...................................................................... 5–4
5.4.1 Power Calibrate ...................................................................................... 5–4
5.4.2 Power Set............................................................................................... 5–4
5.4.3 SWR Calibrate ........................................................................................ 5–5
5.4.4 PA Current Limit..................................................................................... 5–5
5.5 Motherboard Adjustments .......................................................................... 5–5
5.6 Display Modulation Calibration ................................................................... 5–5
5.7 Voltage Regulator Adjustments .................................................................. 5–5
5.8 Performance Verification ............................................................................ 5–6
5.8.1 Audio Proof-of-Performance Measurements.......................................... 5–6
5.8.2 De-emphasis Input Network................................................................... 5–6
5.9 Carrier Frequency ....................................................................................... 5–6
5.10 Output Power.............................................................................................. 5–6
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5.11 RF Bandwidth and RF Harmonics ............................................................... 5–7
5.12 Pilot Frequency ........................................................................................... 5–7
5.13 Audio Frequency Response ........................................................................ 5–7
5.14 Audio Distortion.......................................................................................... 5–7
5.15 Modulation Percentage ............................................................................... 5–7
5.16 FM and AM Noise ....................................................................................... 5–7
5.17 Stereo Separation ....................................................................................... 5–8
5.18 Crosstalk..................................................................................................... 5–8
5.18.1 Main Channel Into Sub ........................................................................... 5–8
5.18.2 Sub Channel Into Main ........................................................................... 5–8
5.19 38–kHz Subcarrier Suppression ................................................................. 5–8
5.20 Additional Checks ....................................................................................... 5–8
Section 6—Reference Drawings
6.1 Views.......................................................................................................... 6–2
6.2 Board Layouts and Schematics .................................................................. 6–4
Audio Processor ......................................................................................... 6–5
Stereo Generator ........................................................................................ 6–7
RF Exciter ................................................................................................... 6–9
Metering ................................................................................................... 6–11
Motherboard............................................................................................. 6–13
Display...................................................................................................... 6–15
Voltage Regulator ..................................................................................... 6–17
Power Regulator....................................................................................... 6–19
RF Output Amplifier .................................................................................. 6–21
Quadrature Power Combiner .................................................................... 6–22
RF Input.................................................................................................... 6–23
DC Input ................................................................................................... 6–24
RF Output Filter and Reflectometer........................................................... 6–26
FM Predriver ............................................................................................. 6–28
Chassis Wiring.......................................................................................... 6–29
Receiver Board ......................................................................................... 6–31
Section 7—Service and Support
7.1 Service........................................................................................................ 7–2
7.2 24–Hour Support........................................................................................ 7–2
7.3 Spare Parts................................................................................................. 7–2
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I
INFORMATION
Section 1—Getting Acquainted
This section provides a general description of the FM250G
transmitter and introduces you to safety conventions used within
this document. Review this material before installing or
operating the transmitter.
Getting Acquainted
1—1
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1.1
Your Transmitter
The FM250G is a member of a family of FM stereo broadcast transmitters. Crown
transmitters are known for their integration, ease-of-use, and reliability.
The integration is most apparent in the standard transmitter configuration which
incorporates audio processing, stereo generation, and RF amplification without
compromised signal quality. A single Crown transmitter can replace several pieces
of equipment in a traditional system.
Ease-of-use is apparent in the user-friendly front panel interface and in the
installation procedure. Simply select your operating frequency add an audio source,
attach an antenna, and connect AC power and you're ready to broadcast. Of course,
the FM series of transmitters also feature more sophisticated inputs and monitoring
connections if needed.
Reliability is a Crown tradition. The first Crown transmitters were designed for
rigors of worldwide and potentially portable use. The modular design, quality
components, engineering approach, and high production standards ensure stable
performance. For more direct monitoring, the front panel includes a digital
multimeter display and status indicators. Automatic control circuitry provides
protection for high VSWR as well as high current, voltage, and temperature
conditions.
Illustration 1–1 FM250G FM Broadcast Transmitter
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FM250G User’s Manual
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1.2
Applications and Options
Crown transmitters are designed for versatility in applications. They have been used
as stand-alone and backup transmitters and in booster, translator, satellator, and
nearcast applications. The following discussion describes these applications further.
Model numbers describe the configuration of the product (which has to do with its
intended purpose) and the RF output power which you can expect.
The number portion of each name represents the maximum RF output power. The
FM250G, for example, can generate up to 250 watts of RF output power.
Suffix letters describe the configuration. The FM250GT, for example, is the standard
or transmitter configuration. Except where specified, this document describes the
transmitter configuration. In this configuration, the product includes the following
components (functions):
•
•
•
•
•
audio processor
stereo generator
RF exciter
metering
low-pass filter
RF Exciter
Stereo
Generator
Low-Pass
Filtering
Metering
Audio
Processor
Illustration 1–2 Standard (Transmitter) Configuration
Getting Acquainted
1—3
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1.2.1
Stand-Alone
In the standard configuration, the FM250G is an ideal stand-alone transmitter.
When you add an audio source (monaural, L/R stereo, or composite signal), an
antenna, and AC power, the transmitter becomes a complete FM stereo broadcast
station, capable of serving a community.
As stand-alone transmitters, Crown units often replace multiple pieces of
equipment in a traditional setup (exciter, audio processor, RF amplifier).
1.2.2
Backup
In the standard configuration, Crown transmitters are also used in backup
applications. Should your primary transmitter become disabled, you can continue
to broadcast while repairs take place. In addition, the FM transmitters can replace
disabled portions of your existing system including the exciter, audio processor, or
amplifier. Transfer switches on each side of the existing and backup transmitters
make the change-over possible with minimal downtime.
1.2.3
Booster
Also in the standard configuration, Crown transmitters have been used as booster
transmitters. Booster applications typically involve certain geographic factors which
prevent your system from broadcasting to the full coverage area allowable. For
example, a mountain range might block your signal to a portion of your coverage
area. Careful placement of a Crown transmitter, operating on the same frequency as
your primary transmitter, can help you reach full coverage. An external receiver and
special antenna are required to use Crown FM transmitters as boosters.
1.2.4
Exciter
In addition to the standard configuration, Crown FM transmitters are available in
optional configurations to meet a variety of needs.
An “E” suffix, as in the FM30GE, for example, represents an exciter-only
configuration. In this configuration, the audio processor and stereo generator
boards are replaced with circuitry to bypass their function. The exciter
configurations are the least expensive way to get Crown-quality components into
your transmission system.
You might consider the Crown exciter when other portions of your system are
performing satisfactorily and you want to maximize your investment in present
equipment.
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FM250G User’s Manual
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1.2.5
Translator
The FM30GR receiver option replaces the audio processor and stereo generator
boards with a receiver module. This added feature makes Crown transmitters ideal
for translator service in terrestrial-fed networks. These networks represent a
popular and effective way to increase your broadcasting coverage. Translators,
acting as repeater emitters, are necessary links in this chain of events.
Traditionally, network engineers have relied on multiple steps and multiple pieces of
equipment to accomplish the task. Others have integrated the translator function
(receiver and exciter) to feed an amplifier. Crown, on the other hand, starts with an
integrated transmitter and adds a solid-state Receiver Module to form the ideal
translator.
Receiver
Module
(Option)
RF In
Low-Pass
Filter
RF Out
RF Exciter
Metering
Illustration 1–3 Crown’s Integrated Translator
This option enables RF in and RF out on any of Crown’s FM series of transmitters.
In addition, the module supplies a composite output to the RF exciter portion of the
transmitter. From here, the signal is brought to full power by the built-in power
amplifier for retransmission. The Receiver Module has been specifically designed to
handle SCA channel output up to 100 kHz for audio and high-speed data.
FSK ID programming is built-in to ensure compliance with regulations regarding
the on-air identification of translators. Simply specify the call sign of the repeater
station when ordering. Should you need to change the location of the translator,
replacement FSK chips are available. The Receiver Module option should be ordered
at the time of initial transmitter purchase. However, an option kit is available for
field converting existing Crown units.
In the translator configuration there are differences in the function of the front
panel, See Section 3.7, Digital Multimeter for a description.
Getting Acquainted
1—5
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1.2.6
Satellator
Crown transmitters include automatic call sign or operating frequency
transmission in a Morse code style. This feature is intended for use in satellite-fed
networks. Transmitters equipped in this fashion are often known as “satellators.”
Connect the transmitter to your satellite receiver and the built-in FSK IDer does the
rest—shifting the frequency in a manner that is unnoticeable to the listener.
1.2.7
Nearcasting
Some Crown units function as “nearcast” transmitters. Their low-power output is
not designed for broadcasting a signal but for transmitting it to local receivers,
sometimes within the same room. Crown transmitters have been used in this way
for language translation, for rebroadcasting the audio of sporting events within a
stadium, and for specialized local radio. Crown makes a dedicated nearcast
transmitter. However, the FM250G is also appropriate for this application.
1—6
FM250G User’s Manual
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1.3
Transmitter/Exciter Specifications
=
Frequency Range
87-108 MHz
RF Power Output
(VSWR 1.5:1 or better)
50-250 watts, adjustable
RF Output Impedance
50 Ω
Audio Input Impedance
50 kΩ bridging, balanced, or 600 Ω
Audio Input Level
Selectable for -10 dBm to +10 dBm for
75 kHz deviation at 400 Hz
Pre-emphasis
Selectable for 25, 50, or 75 µsec; or Flat
Audio Response
Conforms to 75 µsec pre-emphasis curve
as follows
Complete transmitter
±0.30 dB (50 Hz-10 kHz)
±1.0 dB (10 kHz-15 kHz)
Exciter only
±0.25 dB (50 Hz-15 kHz
Distortion (THD + Noise)
Complete transmitter
Less than 0.7% (at 15 kHz)
Exciter only
Less than 0.3% (50 Hz-15 kHz)
Stereo Separation
Complete transmitter
Better than -40 dB (50 Hz-15 kHz)
Exciter only
Better than -40 dB (50 Hz-15 kHz)
Crosstalk
Main into sub, better than -40 dB
Sub into main, better than -40 dB
Stereo Pilot
19 kHz ±2 Hz, 9% modulation
Subcarrier Suppression
50 dB below ±75 kHz deviation
FM S/N Ratio (FM noise)
Complete transmitter
Better than -60 dB
Exciter only
Better than -70 dB
RF Bandwidth
±120 kHz, better than -35 dB
±240 kHz, better than -45 dB
RF Spurious Products
Getting Acquainted
Better than -70 dB
1—7
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Operating Environment
Temperature (0o C -50o C)
Humidity (0-80% at 20o C)
Maximum Altitude (3,000 meters; 9843
feet)
AC Power
90-264 volts; 650 VA at 120 or 240 volts
AC
Note: Note: We set voltage and ampere requirements to assist you in
designing your system. Depending on your operating frequency,
actual requirements for maximum voltage and current readings are
10-15% lower than stated.
Regulatory
Meets CE and TUV requirements
Dimensions
13.5 x 41.9 x 44.5 cm
(5.25 x 16.5 x 17.5 inches)
Weight
1.4
13.6 kg (30 lbs) shipping weight
Receiver Specifications
Monaural Sensitivity
(demodulated, de-emphasized)
3.5 µV for signal-to-noise > 50 dB
12.6 µV for signal-to-noise > 60 dB
Stereo Sensitivity
(19–kHz pilot frequency added)
2.8 µV for signal-to-noise > 40 dB
8 µV for signal-to-noise > 50 dB
31 µV for signal-to-noise > 60 dB
Connector
Standard type N, 50 Ω
Shipping Weight
1 lb
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FM250G User’s Manual
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1.5
Safety Considerations
Crown Broadcast assumes the responsibility for providing you a safe product and
safety guidelines during its use. “Safety” means protection to all individuals who
install, operate, and service the transmitter as well as protection of the transmitter
itself. To promote safety, we use standard hazard alert labeling on the product and
in this manual. Follow the associated guidelines to avoid potential hazard.
1.5.1
Dangers
DANGER represents the most severe hazard alert. Extreme bodily harm or death
will occur if DANGER guidelines are not followed.
1.5.2
Warnings
WARNING represents hazards which could result in severe injury or death.
1.5.3
Cautions
CAUTION indicates potential personal injury, or equipment or property damage if
the associated guidelines are not followed. Particular cautions in this text also
indicate unauthorized radio-frequency operation.
Pictorial or
written
description
of hazard
DANGER
Severity of
hazard
Sever shock hazard!
Turn power off and wait
approximtely 1 minute for
capcitors to discharge before
handling them.
Explanation of
hazard
Illustration 1–4 Hazard Warning
Getting Acquainted
1—9
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FM250G User’s Manual
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Section 2—Installation
This section provides important guidelines for installing your
transmitter. Review this information carefully for proper
installation.
Installation
2—1
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CAUTION
Possible equipment damage!
Before operating the transmitter for the first
time, check for the proper AC line voltage setting and frequency described in Section 2.2,
Power Connections and Section 2.3, Frequency
(Channel) Selection.
2.1
Operating Location
You can install the FM transmitter in a standard component rack or on a suitable
surface such as a bench or desk. In any case, the area should be as clean and wellventilated as possible. Always allow for at least 2 cm of clearance under the unit for
ventilation. If you set the transmitter on a flat surface, install spacers on the bottom
cover plate. If you install the transmitter in a rack, provide adequate clearance above
and below. Do not locate the transmitter directly above a hot piece of equipment.
2.2
Power Connections
The FM250G operates on 120 or 240 volts AC (50 or 60 Hz; single phase). As
shipped (factory default settings), the FM250G operates on 240 volts at 60 Hz.
If you are operating the transmitter at 240 volts you do not need to make any
changes. To operate the FM250G at 120 volts, make the following changes.
To change the voltage setting, perform the following steps:
1. Disconnect the power cord if it is attached.
2. Open the cover of the power connector assembly using a small, flat blade
screwdriver. See Illustration 2–1, Opening the Power Connector Cover.
3. Insert the screwdriver into the top slot of the voltage selection assembly (red)
and pry out the assembly from the power connector.
4. If you are setting the input voltage for 120 volts, replace the installed fuses
with 10 amp fuses (included in your package). See Illustration 2–2, Removing
the Voltage Selection (red) Assembly.
5. Replace the red fuse assembly so that the "120V" setting appears right side up
in the window. Close the assembly window.
2—2
FM250G User’s Manual
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115V
Illustration 2–1 Opening the Power Connector Cover
115V
230V
Illustration 2–2 Removing the Voltage Selection (red) Assembly
6. Connect the AC power cord.
Input Power
Fuze Size
120 VAC
10 ampere
240 VAC
4 ampere
Table 2-1 Fuse Size
Installation
2—3
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2.3
Frequency (Channel) Selection
You may select an operating frequency of 87 to 108 MHz in the FM broadcast band.
Pins 2 and 3 of JP1 on the RF Exciter board are jumpered for these frequencies.
To adjust the operating frequency, follow these steps:
1. Remove the top cover by removing 18 screws.
2. Locate the RF Exciter board and identify the frequency selector switches which
will be used to change the setting. See Illustration 2–3, Top Cover Removed,
and Illustration 2–4, RF Exciter Board (Frequency Selector Switches)..
Modulation
Trim-pot
Frequency
Selection Rotary
RF Exciter
FM250
fi
Illustration 2–3 Top Cover Removed
MEGAHERTZ
.1
.01
Illustration 2–4 RF Exciter Board (Frequency Selector Switches)
3. Use small flat blade screwdriver or another suitable device to rotate the
switches to the desired setting. (The selected number will appear directly
above the white indicator dot on each switch.) See examples of selected frequencies in the illustration below.
= 88.1 MHz
= 107.9 MHz
Illustration 2–5 Example Frequency Selections
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FM250G User’s Manual
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2.3.1
Modulation Compensator
The Modulation trim-potentiometer, (see Section 2–6, Modulation Compensator
Settings), compensates for slight variations in deviation sensitivity with frequency.
Set the trim-pot dial according to the following graph:
Modulation Compensation Pot Setting
90
80
70
60
50
40
30
20
10
0
75
80
85
90
95
100
105
110
Frequency (MHz)
Illustration 2–6 Modulation Compensator Settings
These compensator settings are approximate. Each mark on the potentiometer
represents about 1.8% modulation compensation. For more exact settings, see
Section 5.2.2, Composite Output.
Replace the top cover before operating the transmitter.
2.3.2
RF Tuning Adjustments
All the RF stages are broadband to cover the 88 to 108 MHz broadcast band. The RF
amplifier stages require no tuning.
Note: If you requested it, the FSK chip on the RF Exciter Board has been
pre-programmed for your operating frequency. This chip is
replaceable. Should you need to change the location of your
translator, contact Crown Broadcast for a replacement chip with your
new FSK ID. To disable auto ID, remove the jumper from the auto ID
location on header HD2 on the RF Exciter Board.
Installation
2—5
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2.4
Receiver Frequency Selection
If you have a transmitter equipped with the receiver option, you will need to set the
receiving or incoming frequency.
1. With the top cover removed, locate the receiver module and the two switches
(labeled SW1 and SW2).
Receiver
Module
Frequency Selection
Switches
Illustration 2–7 Receiver Module Switches
2. Use Table 2-2, Receiver Frequency Selection, to set the switches for the desired
incoming frequency.
After setting the frequency, return to Section 2.3.1, Modulation Compensator, to set
the modulation compensator.
Note: If you requested it, the FSK chip on the RF Exciter Board has been
pre-programmed for your operating frequency. This chip is
replaceable. Should you need to change the location of your
translator, contact Crown Broadcast for a replacement chip with your
new FSK ID.
Replace the top cover before operating the transmitter.
2—6
FM250G User’s Manual
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Frequency
87.9
88.0
88.1
88.2
88.3
88.4
88.5
88.6
88.7
88.8
88.9
89.0
89.1
89.2
89.3
89.4
89.5
89.6
89.7
89.8
89.9
90.0
90.1
90.2
90.3
90.4
90.5
90.6
90.7
90.8
90.9
91.0
91.1
91.2
91.3
91.4
91.5
91.6
91.7
91.8
91.9
92.0
92.1
92.2
92.3
92.4
92.5
92.6
92.7
92.8
SW1
0
8
0
8
0
8
0
8
0
8
0
8
0
8
0
8
0
8
0
8
0
8
0
8
0
8
0
8
0
8
0
8
1
9
1
9
1
9
1
9
1
9
1
9
1
9
1
9
1
9
SW2
0
0
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
A
A
B
B
C
C
D
D
E
E
F
F
0
0
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
Frequency
92.9
93.0
93.1
93.2
93.3
93.4
93.5
93.6
93.7
93.8
93.9
94.0
94.1
94.2
94.3
94.4
94.5
94.6
94.7
94.8
94.9
95.0
95.1
95.2
95.3
95.4
95.5
95.6
95.7
95.8
95.9
96.0
96.1
96.2
96.3
96.4
96.5
96.6
96.7
96.8
96.9
97.0
97.1
97.2
97.3
97.4
97.5
97.6
97.7
97.8
SW1
1
9
1
9
1
9
1
9
1
9
1
9
1
9
2
A
2
A
2
A
2
A
2
A
2
A
2
A
2
A
2
A
2
A
2
A
2
A
2
A
2
A
2
A
2
A
3
B
3
B
SW2
9
9
A
A
B
B
C
C
D
D
E
E
F
F
0
0
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
A
A
B
B
C
C
D
D
E
E
F
F
0
0
1
1
Frequency SW1
97.9
3
B
98.0
98.1
3
98.2
B
98.3
3
98.4
B
98.5
3
98.6
B
98.7
3
98.8
B
98.9
3
B
99.0
99.1
3
99.2
B
99.3
3
99.4
B
99.5
3
99.6
B
99.7
3
99.8
B
99.9
3
B
100.0
100.1
3
100.2
B
100.3
3
100.4
B
100.5
3
100.6
B
100.7
4
100.8
C
100.9
4
C
101.0
101.1
4
101.2
C
101.3
4
101.4
C
101.5
4
101.6
C
101.7
4
101.8
C
101.9
4
C
102.0
102.1
4
102.2
C
102.3
4
102.4
C
102.5
4
102.6
C
102.7
4
102.8
C
SW2
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
A
A
B
B
C
C
D
D
E
E
F
F
0
0
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
A
A
Frequency
102.9
103.0
103.1
103.2
103.3
103.4
103.5
103.6
103.7
103.8
103.9
104.0
104.1
104.2
104.3
104.4
104.5
104.6
104.7
104.8
104.9
105.0
105.1
105.2
105.3
105.4
105.5
105.6
105.7
105.8
105.9
106.0
106.1
106.2
106.3
106.4
106.5
106.6
106.7
106.8
106.9
107.0
107.1
107.2
107.3
107.4
107.5
107.6
107.7
107.8
107.9
108.0
SW1
4
C
4
C
4
C
4
C
4
C
5
D
5
D
5
D
5
D
5
D
5
D
5
D
5
D
5
D
5
D
5
D
5
D
5
D
5
D
5
D
5
D
6
E
6
E
6
E
6
E
6
E
SW2
B
B
C
C
D
D
E
E
F
F
0
0
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
A
A
B
B
C
C
D
D
E
E
F
F
0
0
1
1
2
2
3
3
4
4
Table 2-2 Receiver Frequency Selection
Installation
2—7
Rev A
2.5
RF Connections
Connect the RF load, antenna or the input of an external power amplifier, to the
type-N, RF output connector on the rear panel. VSWR should be 1.5:1 or better.
Warning
Severe shock hazard!
Do not touch the inner portion of the RF
output connector when transmitter power is
on.
The RF monitor is intended primarily for a modulation monitor connection.
Information gained through this connection can supplement that which is available
on the transmitter front panel displays.
If your transmitter is equipped with the receiver option, connect the incoming RF
to the RF IN connector.
RF Output
RF Input Connector
(receiver option only)
120Vac
RF Output
Monitor
Illustration 2–8 RF Connection
2—8
FM250G User’s Manual
Rev A
2.6
Audio Input Connections
Attach audio inputs to the Left and Right XLR connectors on the rear panel. (The
Left channel audio is used on Mono.) Pin 1 of the XLR connector goes to chassis
ground. Pins 2 and 3 represent a balanced differential input with an impedance of
about 50 kΩ. They may be connected to balanced or unbalanced left and right
program sources.
The audio input cables should be shielded pairs, whether the source is balanced or
unbalanced. For an unbalanced program source, one line (preferably the one
connecting to pin 3) should be grounded to the shield at the source. Audio will then
connect to the line going to pin 2.
SCA IN
RIGHT
MONITOR
COMPOSITE IN
R
LEFT/MONO
L
REMOTE I/O
1
2
3
Audio
Inputs
Illustration 2–9 XLR Audio Input Connections
By bringing the audio return line back to the program source, the balanced
differential input of the transmitter is used to best advantage to minimize noise.
This practice is especially helpful if the program lines are fairly long, but is a good
practice for any distance.
If the program source requires a 600 Ω termination, install resistors on the 8–pin
DIP socket on the motherboard (socket A501 located between the XLR connectors).
See Section 6.2, Board Layouts and Schematics.
Installation
2—9
Rev A
2.7
SCA Input Connections
You can connect external SCA generators to the SCA In connectors (BNC-type) on
the rear panel. The inputs are intended for the 60 kHz to 99 kHz range, but a lower
frequency may be used if the transmitter is operated in Mono mode. (The 23 to 53
kHz band is used for stereo transmission.) For 7.5 kHz deviation (10% modulation),
input of approximately 3.5–volts (peak-to-peak) is required
SCA IN
RIGHT
MONITOR
COMPOSITE IN
R
LEFT/MONO
L
REMOTE I/O
1
2
3
SCA Inputs
Illustration 2–10 SCA Input Connections
2.8
Composite Input Connection
You may feed composite stereo (or mono audio) directly to the RF exciter, bypassing
the internal audio processor and stereo generator. To use the Crown transmitter as
an RF Exciter only (“E” version or when using the “T” version with composite
input), it is necessary to use the Composite Input section of the transmitter. This
will feed composite stereo (or mono audio) directly to the RF exciter. In the “T”
version, this will bypass the internal audio processor and stereo generator. See
Section 2.11 on the next page for caution in using the bypass option.
Input sensitivity is approximately 3.5–volt P-P for 75 kHz deviation.
1. Enable the Composite Input by grounding pin 9 of the Remote I/O connector
(see Section 2–13, Remote I/O Connector).
2. Connect the composite signal to the Composite In BNC connector.
2—10
FM250G User’s Manual
Rev A
SCA IN
RIGHT
MONITOR
COMPOSITE IN
R
LEFT/MONO
L
REMOTE I/O
1
2
3
Composite In
BNC Connector
Audio Monitor
Jacks
Illustration 2–11 Composite In and Audio Monitor Connections
2.9
Audio Monitor Connections
Processed, de-emphasized samples of the left and right audio inputs to the stereo
generator are available at the Monitor jacks on the rear panel. The signals are
suitable for feeding a studio monitor and for doing audio testing. De-emphasis is
normally set for 75 µsec.; set to 50 µsec. by moving jumpers, JP203 and JP204, on
the Stereo Generator board. See Section 5.8.2, De-emphasis Input Network, for
further information.)
2.10
Pre-emphasis Selection
Select the pre-emphasis curve (75 µsec., 50 µsec., 25 µsec., or Flat) by jumpering
the appropriate pins of header JP1 on the audio processor board. If you change the
pre-emphasis, change the de-emphasis jumpers JP203 and JP204 on the Stereo
Generator board to match. (See Section 2.8, Composite Input Connection for
additional information.)
2.11
Processor Bypass Option
You may bypass the audio processor in order to feed the left and right (preemphasized) audio directly to the stereo generator. The Normal-Bypass slide switch
is near the left-rear corner of the motherboard. If the audio source is already
processed and you do not desire further processing, use the Normal mode, but turn
the Processing control (on the front panel) to “0.” (See also Section 3.4, Processing
Control.)
CAUTION
In the BYPASS position, the pre-emphasis circuits and the filters that protect the
pilot and stereo subcarrier are bypassed. As a result, the occupied bandwidth
specifications of the transmitter could be compromised. The 15–Hz high-pass
filters are also bypassed which may mean that modulation with frequencies below
10 Hz could cause the frequency synthesizer to unlock.
Installation
2—11
Rev A
2.12
Program Input Fault Time-out
You can enable an automatic turn-off of the carrier in the event of program failure.
To enable this option, selecte a setting from Table 2-3, Fault Time-out Values. The
time between program failure and carrier turn-off is set by a jumper (JP701) on the
voltage regulator board. (See Illustration 6-4 , Chassis Bottom View)for board
location).
Delay
30 seconds
2 minutes
4 minutes
8 minutes
Pins to Jumper
1-2 (pins closest to edge)
3-4
5-6
7-8
Table 2-3 Fault Time-out Values
2.13
Remote I/O Connector
Remote control and remote metering of the transmitter is made possible through a
15–pin, D-sub connector on the rear panel. (No connections are required for normal
operation.
Remote I/O
SCA IN
RIGHT
MONITOR
COMPOSITE IN
R
LEFT/MONO
L
REMOTE I/O
1
2
3
Illustration 2–12 Remote I/O Connector
Table 2-4, Remote I/O Connector, summarizes the Remote I/O pin connections.
2—12
FM250G User’s Manual
Rev A
Pin Number
Function
1
Ground
2
(no connection)
3
Composite Out (sample of stereo generator output)
4
FSK In (Normally high; pull low to shift carrier frequency approximately 7.5 kHz. Connect to open collector or relay contacts of
user-supplied FSK keyer.)
5
/Auto Carrier Off (Pull low to enable automatic turnoff of carrier
with program failure.)
6
Meter Battery (unregulated DC voltage; 5 volts = 50 VDC)
7
Meter RF Watts (1 volt = 100 watts)
8
Meter PA Volts (5 volts = 50 VDC)
9
/Ext. Enable (Pull low to disable internal stereo generator and
enable External Composite Input.)
10
a) 38 kHz Out (From stereo generator for power supply synchronization.)
b) For transmitters equipped with tuner option, this pin becomes
the right audio output for an 8–ohm monitor speaker. 38kHZ Out
is disabled.
11
ALC
12
/Carrier Off (pull low to turn carrier off.)
13
Fault Summary (line goes high if any fault light is activated.)
14
Meter PA Temperature (5 volts = 100 degrees C.)
15
Meter PA Current (1 volt = 10 amperes DC.)
Table 2-4 Remote I/O Connector
1
8
15
9
Illustration 2–13 Remote I/O Connector
Installation
2—13
Rev A
2—14
FM250G User’s Manual
Section 3—Operation
This section provides general operating parameters of your
transmitter and a detailed description of its front panel display.
Operation
3—1
Rev A
3.1
FM250G Initial Power-up Procedures
These steps summarize the operating procedures you should use for the initial
operation of the transmitter. More detailed information follows.
Caution
Possible equipment damage!
Before operating the transmitter for the first
time, check for the proper AC line voltage
setting and frequency selection as described
in Section 2.2 and 2.3.
1. Turn on the main power switch.
Carrier
Switch
Main
Power
Switch
Illustration 3-1 Front Panel Power Switches
2. Verify the following:
a. The bottom cooling fan runs continuously.
b. The Lock Fault indicator flashes forapproximately 5 seconds, then goes off.
3. Set the Input Gain switches for mid-scale wideband gain reduction on an average program level (see Section 3.3, Input Gain Switches).
4. Set the Processing control (see Section 3.4, Processing Control; normal setting is “50”).
5. Set the Stereo-Mono switch to Stereo (see Section 3.5, Stereo-Mono Switch).
6. Turn on the Carrier switch.
7. Check the following parameters on the front panel multimeter:
a. RF Power should be 250–275 watts.
b. SWR should be less than 1.1. (A reading greater than 1.25 indicates an
antenna mismatch.
c. ALC should be between 3.50 and 5.50 volts.
d. PA DC Volts should be 35 to 45 volts. (Varies with antenna match, power,
and frequency.)
e. PA DC Amperes should be 10-12 amps for the FM250G. (Varies with
3—2
FM250G User’s Manual
Rev A
antenna match, power, and frequency.)
f.
PA Temperature should initially read 20–35 degrees C (room temperature).
After one hour the reading should be 45-55 degrees C. Maximum operating
temperature is 55 degrees C.
g. Supply DC volts should display a typical reading of 55-56 volts with the
carrier on or off.
h. Voltmeter should be reading 0.0.
The remainder of this section describes the functions of the front panel indicators
and switches.
3.1.1
Power Switch
The main on/off power switch controls the 120/240 VAC.
3.1.2
Carrier Switch
This switch controls power to the RF amplifiers and supplies a logic high to the
voltage regulator board, which enables the supply for the RF driver. In addition, the
Carrier Switch controls the operating voltage needed by the switching power
regulator.
A “Lock Fault” or a low pin 12 (/Carrier Off) on the Remote I/O connector will hold
the carrier off. (See Illustration 2–13, Remote I/O Connector)
Carrier
Switch
Main
Power
Switch
Illustration 3-2 Front Panel Power Switches
Operation
3—3
Rev A
3.2
Front Panel Bar-Dot Displays
Bar-dot LEDs show audio input levels, wideband and highband audio gain control,
and modulation percentage. Resolution for the gain control and modulation
displays is increased over a conventional bar-graph display using dither
enhancement which modulates the brightness of the LED to give the effect of a fade
from dot to dot. (Section 4.7, Display Circuit Board)
3.2.1
Audio Processor Input
Two vertical, moving-dot displays for the left and right channels indicate the relative
audio levels, in 3 dB steps, at the input of the audio processor. Under normal
operating conditions, the left and right Audio Processor indicators will be active,
indicating the relative audio input level after the Input Gain switches. During
program pauses, the red Low LED will light.
The translator configuration shows relative audio levels from the included receiver.
3.2.2
Highband and Wideband Display
During audio processing, the moving-dot displays indicate the amount of gain
control for broadband (Wide) and pre-emphasized (High) audio.
As long as program material causes activity of the Wideband green indicators,
determined by the program source level and Input Gain switches, the transmitter
will be fully modulated. (See Section 3.3, Input Gain Switches)
The Wideband indicator shows short-term “syllabic-rate” expansion and gain
reduction around a long-term (several seconds) average gain set. In the translator
configuration, the Wideband indicator also shows relative RF signal strength.
Program material and the setting of the Processing control determine the
magnitude of the short-term expansion and compression (the rapid left and right
movement of the green light).
High-frequency program content affects the activity of the Highband indicator.
With 75–µsec pre-emphasis, Highband processing begins at about 2 kHz and
increases as the audio frequency increases. Some programs, especially speech, may
show no activity while some music programs may show a great deal of activity.
3.2.3
Modulation Display
A 10–segment, vertical peak-and-hold, bar graph displays the peak modulation
percentage. A reading of “100” coincides with 75 kHz deviation. The display holds
briefly (about 0.1 seconds) after the peak. The “Pilot” indicator illuminates when
the transmitter is in the stereo mode.
To verify the actual (or more precise) modulation percentage, connect a certified
modulation monitor to the RF monitor jack on the rear panel.
3—4
FM250G User’s Manual
Rev A
3.3
Input Gain Switches
The “+6 dB” and “+12 dB” slide switches set audio input sensitivity according to the
following table.
Nominal Input Sensitivity
+10 dBm
+4 dBm
-2 dBm
-8 dBm
Switches
+6 dB
Down
Up
Down
Up
+12 dB
Down
Down
Up
Up
Illustration 3-3 Input Gain Switches
Find, experimentally, the combination of Input Gain switch settings that will bring
the Wideband gain-reduction indicator to mid scale for “normal” level program
material. The audio processor will accommodate a fairly wide range of input levels
with no degradation of audio quality.
3.4
Processing Control
Two factors contribute to the setting of the Processing control: program material
and personal taste. For most program material, a setting in the range of 40 to 70
provides good program density. For the classical music purist, who might prefer
preservation of music dynamics over density, 10 to 40 is a good range. The audio
will be heavily processed in the 70 to 100 range.
If the program source is already well processed, as might be the case with a satellite
feed, set the Processing to “0” or “10”.
3.5
Stereo-Mono Switch
The Stereo-Mono slide switch selects the transmission mode. In Mono, feed audio
only to the left channel. Although right-channel audio will not be heard as audio
modulation, it will affect the audio processing.
Operation
3—5
Rev A
3.6
RF Output Control
Set this control for the desired output power level. Preferably, set the power with an
external RF wattmeter connected in the coaxial line to the antenna. You may also
use the RF power reading on the digital multimeter.
The control sets the RF output voltage. Actual RF output power varies as the
approximate square of the relative setting of the control. For example, a setting of
“50” is approximately 1/4 full power. Operation below 10 watts is not recommended.
3.7
Digital Multimeter
The four-digit numeric display in the center of the front panel provides information
on transmitter operation. Use the “Up” and “down” push-buttons to select one of
the following parameters. A green LED indicates the one selected.
Multimeter
Multimeter Functions
Multimeter Push-buttons
Illustration 3-4 Digital Multimeter
RF Power—Actually reads RF voltage squared, so the accuracy can be affected by
VSWR (RF voltage-to-current ratio). See Section 5.4, Metering Board Adjustments,
for calibration. Requires calibration with the RF reflectometer being used.
SWR—Direct reading of the antenna standing-wave ratio (the ratio of the desired
load impedance, 50 ohms, to actual load).
ALC—DC gain control bias used to regulate PA supply voltage. With the PA power
supply at full output voltage, ALC will read about 6.0 volts. When the RF output is
being regulated by the RF power control circuit, this voltage will be reduced,
typically reading 4 to 5.5 volts. The ALC voltage will be reduced during PA DC
overcurrent, SWR, or LOCK fault conditions.
PA DC Volts—Supply voltage of the RF power amplifier.
PA DC Amps—Transistor drain current for the RF power amplifier.
PA DC Temperature—Temperature of the RF power amplifier heatsink in degrees C.
Supply DC Volts—Unregulated DC voltage at the input of the voltage regulators.
3—6
FM250G User’s Manual
Rev A
Voltmeter—Reads the voltage at a test point located on the front edge of the
motherboard. A test lead connected to this point can be used for making voltage
measurements in the transmitter. The test point is intended as a servicing aid; an
alternative to an external test meter. Remember that the accuracy is only as good as
the reference voltage used by the metering circuit. Servicing a fault affected by the
reference affects the Voltmeter reading. The metering scale is 0 to 199.9 volts.
In the translator configuration, you can read a relative indication of RF signal
strength numerically in the Voltmeter setting.
3.8
Fault Indicators
Faults are indicated by a blinking red light as follows:
SWR—Load VSWR exceeds 1.5:1. ALC voltage is reduced to limit the reflected RF
power.
Lock—Frequency synthesizer phase-lock loop is unlocked. This indicator normally
blinks for about five seconds at power turn-on. Whenever this light is blinking,
supply voltages will be inhibited for the RF driver stage as well as for the RF power
amplifier.
Input—The automatic carrier-off circuit is enabled (see Section 2.11, Processor
Bypass Option and Section 2.12, Program Input Fault Time-out) and the absence of
a program input signal has exceeded the preset time.
Note: The circuit treats white or pink noise as an absence of program audio.
Identical left and right but out of phase signals will also cause a fault.
PA DC—Power supply current for the RF power output amplifier is at the preset
limit. ALC voltage has been reduced, reducing the PA supply voltage to hold supply
current to the preset limit.
PA Temp—PA heatsink temperature has reached 70° C (158° F).
At about 72°C (162° F), ALC voltage begins to decrease, reducing the PA supply
voltage to prevent a further increase in temperature. By 75° C (167° F), the PA will
be fully cut off. The heatsink fan is proportionally controlled to hold the heatsink at
35° C (95° F). Above this temperature, the fan runs at full speed.
Operation
3—7
Rev A
3—8
FM250G User’s Manual
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Section 4—Principles of Operation
This section discusses the circuit principles upon which the
transmitter functions. This information is not needed for day-today operation of the transmitter but may be useful for advanced
users and service personnel.
Principles of Operation
4—1
Rev A
4.1
Part Numbering
As this section refers to individual components, you should be familiar with the part
numbering scheme used. Although parts on the various circuit boards and circuit
board drawings may be marked with identical reference numbers, each component
in the transmitter has a unique part reference number.
The circuit boards and component placement drawings use designators such as
“R1”, “R2”, and “C1.” These numbers represent only a portion of the full part
numbers (as shown on the schematic). To find the full number, refer to the chart
below. R401, for instance, is marked “R1” on the Metering board and on its
component placement drawing.
Circuit Name
Audio Processor
Stereo Generator
RF Exciter/Synthesizer
Metering/Protection
Motherboard
Display
Voltage Regulator
Power Regulator
RF Predriver
Chassis Wiring
RF Power Amplifier
RF Low-Pass Filter
Part numbers
0-199
200-299
300-399
400-499
500-599
600-699
700-799
800-899
900-999
1000-1099
1100-1199
1200-1299
Table 4-1 Component Part Numbering
4.2
Audio Processor Circuit Board
The audio processor board provides the audio control functions of a compressor,
limiter, and expander. Illustration 6–5 and accompanying schematic may be useful
to you during this discussion.
Audio
Processor
Illustration 4-1 Audio Processor Board
This board also contains the pre-emphasis networks. Reference numbers are for the
left channel. Where there is a right-channel counterpart, references are in
4—2
FM250G User’s Manual
Rev A
parenthesis. One processor circuit, the eighth-order elliptical filter, is located on the
stereo generator board.
Audio input from the XLR connector on the rear panel of the transmitter goes to
differential-input amplifier, U1A (U2A).
Binary data on the +6 dB and +12 dB control lines sets the gain of inverting
amplifier U1B (U2B). Analog switch, U3, selects one of four feedback points in 6–dB
steps.
The output of U1B (U2B) goes to an eighth-order, elliptical, switched-capacitor,
low-pass, 15.2–kHz filter. The filter finds its home on the stereo generator board to
take advantage of the ground plane and proximity to the 1.52 MHz clock.
The circuit associated with U4B (U4A), along with R22/C8 (R58/C20), form
third-order, low-pass filtering, attenuating audio products below 30 Hz.
The output level of analog multiplier U5 (U6) is the product of the audio signal at
pin 13 and the DC voltage difference between pins 7 and 9. At full gain (no gain
reduction) this difference will be 10 volts DC.
When either the positive or negative peaks of the output of U5 (U6) exceeds the
gain-reduction threshold, U13A generates DC bias, producing broadband gain
reduction. Q5 is a precision-matched transistor pair. Q5 and U13B form a log
converter, so that a given voltage change produces a given change in gain control
dB of U5 (U6). The log conversion ensures uniform level-processing characteristics
well beyond the 20–dB control range. The log conversion has an additional benefit;
it allows a display of gain control on a linear scale with even distribution of dB.
Q1 (Q2) is a recover/expansion gate with a threshold about 18 dB below the normal
program level. The amount of short-term expansion and gain reduction is
controlled by R650, located on the front panel display board. (See section 3.5.)
Pre-emphasis, in microseconds, is the product of the capacitance of C10 (C22),
multiplied by the gain of U8 (U9), times the value of R31 (R67). For a 75–µsecond
pre-emphasis, the gain of U8 (U9) will be about 1.11. Select the pre-emphasis curve
(75 µsec, 50 µsec, 25 µsec, or Flat) by jumpering the appropriate pins on header JP1.
Use trim pot R29 (R65) to make fine adjustments to the pre-emphasis. (See section
5.1.)
For highband processing, the peak output of U10B is detected and gain-reduction
bias is generated, as with the broadband processor. The highband processing,
however, shifts the pre-emphasis curve rather than affecting overall gain.
Peak audio voltages are compared to a plus and minus 5–volt reference, U17 and
U18. This same reference voltage is used by the stereo generator, metering, and
display boards.
For an explanation of on-board adjustments see section 5.1.
Principles of Operation
4—3
Rev A
4.3
Stereo Generator Circuit Board
The stereo generator board (see Illustration 4–3) generates a composite stereo
signal from left and right-channel audio inputs. The component side of the board is
mostly a ground plane. Once again, the eighth-order, 15.2–kHz, elliptical, low-pass
filters (U201 and U202) are on this board, but belong to the audio processor.
Illustration 6–6 and accompanying schematic complement this discussion.
Stereo
Generator
Illustration 4-2 Stereo Generator Board
U207A and Y201 comprise a 7.6–MHz crystal oscillator from which the 19 and 38–
kHz subcarriers are digitally synthesized. U207F is a buffer. The 7.6 MHz is divided
by 5 in U208A to provide 1.52 MHz at pin 6, used by filters U201 and U202. 3.8 MHz,
1.9 MHz, and 304 kHz are also derived from dividers in U208.
Exclusive-OR gates, U210A and U210B, provide a stepped approximation of a 38–
kHz sine wave—a scheme described in the CMOS Cookbook by Don Lancaster
(Howard W. Sams &. Co., Inc., Indianapolis, IN, 1978).
With the resistor ratios used, the synthesized sine wave has very little harmonic
energy below the 7th harmonic. U210C and D generate the 19–kHz pilot subcarrier.
U211 is a dual, switched-capacitor filter, configured as second-order, low-pass filters,
each with a Q of 5. The 38 and 19–kHz outputs of pins 1 and 20, respectively, are
fairly pure sine waves. Harmonic distortion products are better than 66 dB down—
THD of less than 0.05%.
U212 is a precision, four-quadrant, analog multiplier. The output of U212 is the
product of 38 kHz applied to the “X” input and the difference of left and right audio
(L-R signal) applied to the “Y” input. The resulting output is a double sideband,
suppressed carrier—the L-R subcarrier.
The SCA subcarrier, the left, right, and left-minus-right subcarriers, and the 19–kHz
pilot subcarrier are combined into the composite stereo signal by summing
amplifier U206B.
4—4
FM250G User’s Manual
Rev A
Analog switch U205, at the input of U206B, provides switching of left and right
audio for stereo and mono modes. In the mono mode, right channel audio is
disabled, and the left channel audio is increased from 45% modulation to 100%.
MON L and MON R outputs go to the AF Monitor jacks on the rear panel.
R208+R210 (R220+R222) and C207 (C211) comprise a 75–µsec de-emphasis
network. Processed, de-emphasized (75–µsec) samples of the stereo generator input
signals are used for a studio monitor and for audio testing. Option jumpers JP203
(JP204) allow you to select 50 µsec.
VR201 and VR202 supply +6 volts and –6 volts, respectively. A 5–volt reference from
the audio processor board supplies the subcarrier generators.
For an explanation of on-board adjustments see section 5.2.
4.4
RF Exciter Circuit Board
This board is also known as the Frequency Synthesizer board. The entire
component side of the board is a ground plane. Frequency selector switches along
the front edge of the board establish the operating frequency. The VCO
(voltage-controlled oscillator) circuitry is inside a cast aluminum shield cover.
RF
Exciter
Board
Illustration 4-3 RF Exciter Board
Illustration 6–7 and accompanying schematic can be used as reference in this
discussion. The following theory may apply to previous versions of the exciter board,
but it is typical of the operation of the current board.
VCO, Q301, operates at the synthesizer output frequency of 87 MHz to 108 MHz.
The frequency is controlled by voltage-variable capacitors D307 and D308. Q304 and
Q305 form an active filter to supply clean DC to the drain of Q301. Q305 also serves
as a common-base RF amplifier for Q301. U308 and U309 are hybrid RF amplifiers
to provide buffering and gain. (The circuit board has pads for Q302, ALC control of
output. Source and drain pads are jumpered in the transmitter.)
A sample of the RF from the VCO goes to the input of U302. U302 is a dual modulus
10/11 divider that has been connected to divide by 10. The output of U302 is 8.7 to
Principles of Operation
4—5
Rev A
10.8 MHz. This signal, available at TP202, may be used with a high frequency
receiver for deviation and frequency measurements. (See sections 5.2 and 5.3.)
JP301 is a jumper option for bypassing U302 and is used only in transmitters which
have been modified for operating in the Eastern Europe band (66–73 MHz).
U304 is a phase-locked-loop frequency synthesizer IC. The 10.24 MHz from the
crystal oscillator is divided to 10 kHz. Internal programmable dividers (along with
dual modulus divider U301) divide the 8.7 to 10.8 MHz RF to 10 kHz also.
Differences between the two signals produce error signals at pins 7 and 8.
The U304 dividers are set with frequency selector switches. The binary output of the
0.1–MHz switch programs the “A” counter directly. BCD data from the selector
switches is converted to binary data by EPROM U310 to set the “N” counter. There is
also provision on the circuit board for using either DIP switches or jumpers to set
the frequency. (See section 3.3.)
U305B is a differential amplifier and filter for the error signal. Audio that is out of
phase with that appearing on the error voltage is introduced by U305A, allowing for
greater loop bandwidth with less degradation of the low-frequency audio response.
U306B is an integrator. Q303 is a VCO input voltage clamp.
D307 and D308 are hyper-abrupt varactor tuning diodes with a square-law
capacitance vs. DC voltage curve, giving a straight-line frequency vs. voltage curve
in a LC oscillator where the varactors are the dominant source of capacitance.
Lock and unlock status signals are available at the outputs of U303E and U303F,
respectively. Modulation is introduced to the VCO through R351 and R326 to R329.
About 4.1 millivolts across R329 produces 75 kHz deviation.
An FSK signal (used for automatic identification of FM repeaters) shifts the
frequencies of the 10.24–MHz crystal reference and the VCO. With keying, diodes
D310 and D311, are reverse biased, increasing the crystal reference frequency. At
the same time, current through R358 increases the VCO frequency. See section
5.3.4.
4.5
Metering Circuit Board
The ALC and metering circuitry is on the metering board (see Illustration 4–5). This
board processes information for the RF and DC metering, and produces ALC (RF
level-control) bias. It also provides reference and input voltages for the digital panel
4—6
FM250G User’s Manual
Rev A
meter, voltages for remote metering, fan control, and drive for the front-panel fault
indicators.
Metering
Board
Illustration 4-4 Metering Board
Illustration 6–8 and accompanying schematic complement this discussion.
PA voltage and current come from a metering shunt on the power regulator board.
The PAI input is a current proportional to PA current; R405 converts the current to
voltage used for metering and control. A voltage divider from the PAV line is used
for DC voltage metering.
U406A, U406B, and U407A, with their respective diodes, are diode linearity
correction circuits. Their DC inputs come from diode detectors in the RF
reflectometer in the RF low-pass filter compartment.
U407B, U407C, Q405, and Q406 are components of a DC squaring circuit. Since the
DC output voltage of U407C is proportional to RF voltage squared, it is also
proportional to RF power.
U404C, U404A, U403A, and U404D are level sensors for RF power, reflected RF
power, PA temperature, and external PA current, respectively. When either of these
parameters exceeds the limits, the output of U404B will be forced low, reducing the
ALC (RF level control) voltage, which, in turn, reduces the PA supply voltage.
The DC voltage setpoint for U404A (reflected RF voltage) is one-fifth that of U404C
(forward RF voltage). This ratio corresponds to an SWR of 1.5:1 [(1+.2)/(1–.2)=1.5].
The U405 inverters drive the front panel fault indicators.
To get a direct reading of SWR, the reference input of the digital panel meter is fed
from a voltage proportional to the forward-minus-reflected RF voltage, while
forward-plus-reflected is fed to the digital panel meter input. The panel meter
provides the divide function.
Principles of Operation
4—7
Rev A
U408 and U409 function as data selectors for the digital panel meter input and
reference voltages. Binary select data for U408 and U409 comes from the display
board.
The output voltage of U403D goes positive when the temperature exceeds about 35
degrees C (set by R426) providing proportional fan control.
When the Carrier switch is off or the RF power is less than about 5 watts, the SWR
automatically switches to a calibrate-check mode. U406C provides a voltage that
simulates forward power, while Q403 shunts any residual DC from the reflectedpower source. The result is a simulation of a 1.0 to 1 SWR. (See Section 5.4,
Metering Board Adjustments.)
4.6
Motherboard
The motherboard is the large board in the upper chassis interconnecting the audio
processor, stereo generator, RF exciter, and metering boards. The motherboard
provides the interconnections for these boards, eliminating the need for a wiring
harness, and provides input/output filtering.
Motherboard components are passive with the exception of the fan driver transistor,
power FET Q501.
With Normal-Bypass slide switch SW501, it is possible to bypass the audio processor,
connecting the left and right audio inputs directly to the inputs of the stereo
generator.
If the audio source is already processed, and further processing is not desired, use
the Normal mode instead of Bypass and turn the Processing control on the front
panel to “0.”
Caution
In the BYPASS position, the pre-emphasis circuits and the filter
that protect the pilot and stereo subcarrier are bypassed. As a
result, the occupied bandwidth specifications of the transmitter
could be compromised. The 15-Hz high-pass filters are also
bypassed which may mean that modulation with frequencies
below 10 Hz could cause the frequency synthesizer to unlock.
If it is necessary to provide resistive terminations at the audio inputs (either line-toline or line-to-ground), you may place resistors directly into the 8–pin DIP socket,
A501, located between the XLR input connectors. See Illustration 6–9 and
accompanying schematic for the socket pin-out.
4.7
Display Circuit Board
The front-panel LEDs, the numeric display, the slide switches, and the processing
and RF level controls are mounted on the display circuit board. To access the
component side of the board, remove the front panel by removing 12 screws. The
board contains circuits for the digital panel meter, modulation peak detector, and
LED display drivers, as well as indicators and switches mentioned above.
4—8
FM250G User’s Manual
Rev A
Illustration 6–10 and accompanying schematic complement this discussion.
Left and right audio from input stages of the audio processor board (just after the
Input Gain attenuator) go to the L VU and R VU input on the display board. Peak
rectifiers U601A and U601B drive the left and right Audio Input displays. The LED
driver gives a 3–dB per step display. The lowest step of the display driver is not used;
rather a red LOW indicator lights when audio is below the level of the second step.
Transistors Q601 and Q602 divert current from the LOW LEDs when any other LED
of the display is lit.
Resolution of the linear displays, High Band, Wide Band, and Modulation, has been
improved using dither enhancement. With dither, the brightness of the LED is
controlled by proximity of the input voltage relative to its voltage threshold. The
effect is a smooth transition from step to step as input voltage is changed. U606A,
U606B, and associated components comprise the dither generator. Dither output is
a triangular wave.
Composite stereo (or mono) is full-wave detected by diodes D605 and D606. U607,
U613, Q603, and Q604 are components of a peak sample-and-hold circuit.
Oscillator, U609F, supplies a low-frequency square wave to the Fault indicators,
causing them to flash on and off.
Digital multimeter inputs are selected with push buttons located to the right of the
multimeter menu. Signals from the push buttons are conditioned by U609A and
U609B. U610 is an up/down counter. Binary input to U611 from U610 selects a green
menu indicator light, and lights the appropriate decimal point on the numeric
readout. The binary lines also go to analog data selectors on the ALC/metering
board.
Processing control, R650, is part of the audio processor. (See section 4.2.)
The DPM IN and DPM REF lines are analog and reference voltage inputs to digital
multimeter IC U612. They originate from analog data selectors on the ALC/
metering board.
4.8
Voltage Regulator Circuit Board
The voltage regulator board is the longer of two boards mounted under the chassis
toward the front of the unit. It has switch-mode voltage regulators to provide +12, –
12, and 24 volts. It also contains the program detection and automatic carrier
control circuits.
Illustration 6–11 and accompanying schematic complement this discussion.
U703E and U703F convert a 38–kHz sine wave from the stereo generator into a
synchronization pulse. In the transmitter, synchronization is not used, thus D709 is
omitted.
U704 and U705 form a 24–volt switching regulator running at about 35 kHz. U704 is
used as a pulse-width modulator; U705 is a high-side driver for MOSFET switch
Q701. Supply voltage for the two IC’s (approximately 15.5 volts) comes from linear
regulator DZ702/Q705. Bootstrap voltage, provided by D710 and C714, allows the
Principles of Operation
4—9
Rev A
gate voltage of Q701 to swing about 15 volts above the source when Q701 is turned
on. Current through the FET is sensed by R738 and R738A. If the voltage between
pin 5 and 6 of U705 exceeds 0.23 volts on a current fault, drive to Q701 is turned off.
Turn-off happens cycle by cycle. The speed of the turn-off is set by C713.
U706 is a switching regulator for both +12 volts and –12 volts. It runs at about 52
kHz. Energy for –12 volts is taken from inductor L702 during the off portion of the
switching cycle. The –12 volts tracks the +12 volts within a few tenths of a volt.
There will be no –12 volts until current is drawn from the +12 volts.
Q702, Q703, and Q704 form an active filter and switch, supplying DC voltage to the
RF driver, when the Carrier switch is on.
The program detection circuit is made up of U701 and U702. U701A and U701D and
associated circuitry discriminate between normal program material and white noise
(such as might be present from a studio-transmitter link during program failure) or
silence. U701A and surrounding components form a band-pass filter with a Q of 3
tuned to about 5 kHz. U701D is a first-order low-pass filter. Red and green LEDs on
the board indicate the presence or absence of program determined by the balance of
the detected signals from the two filters. U702 and U701C form a count-down timer.
The time between a program fault and shutdown is selected by jumpering pins on
header JP701. For times, see section 5.7. The times are proportional to the value of
R721 (that is, times can be doubled by doubling the value of R721).
4.9
Power Regulator Circuit Board
The power regulator board is the shorter of two boards mounted under the chassis
toward the front of the unit. The board has the isolating diode for the battery input,
the switch-mode voltage regulator for the RF power amplifier, and circuitry for PA
supply current metering.
Illustration 6–12 and accompanying schematic complement this discussion.
Diode D804, in series with the battery input, together with the AC-supply diode
bridge, provides diode OR-ing of the AC and DC supplies.
U801 and U802 form a switching regulator running at about 35 kHz. U801 is used as
a pulse-width modulator; U802 is a high-side driver for MOSFET switch Q801.
Power for the two IC’s comes from the 24–volt supply voltage for the RF driver
(available when the Carrier switch is on). The voltage is controlled at 16 volts by
zener diode DZ801. Bootstrap voltage provided by D802 and C809 allows the gate
voltage of Q801 to swing about 16 volts above the source when Q801 is turned on.
Current through the FET is sensed by R812 and R812A. If the voltage from pin 5 to
6 of U802 exceeds 0.23 volts on a current fault, drive to Q801 is turned off. This
happens on a cycle-by-cycle basis. The speed of the turnoff is set by C805.
In the transmitter, synchronization is not used, thus D801 is omitted.
U803 and Q802 are used in a circuit to convert the current that flows through
metering shunt, R819, into a current source at the collector of Q803. Forty
millivolts is developed across R819 for each amp of supply current (.04 ohms x 1
amp). Q803 is biased by U803 to produce the same voltage across R816. The
collector current of Q803 is the same (minus base current) as that flowing through
4—10
FM250G User’s Manual
Rev A
R822 resulting in 40 microamperes per amp of shunt current. R405 on the metering
board converts Q803 collector current to 0.1 volt per amp of shunt current (.04 ma
X 2.49 k). (See section 5.4.)
4.10
RF Driver
The RF Driver assembly is mounted on a 100 mm x 100 mm plate in the under side
of the chassis. The driver amplifies the approximate 20 milliwatts from the
frequency synthesizer to about 8 watts to drive the RF power amplifier. A CA2832
hybrid, high-gain, wideband amplifier, operating at about 18 volts, provides about
one watt of drive to a single MRF137 MOSFET amplifier. The MRF137 stage operates
from a supply voltage of approximately 18 volts.
The circuit board provides for input/output coupling and for power supply filtering.
4.11
RF Amplifier
The RF power amplifier assembly is mounted on back of the chassis with four
screws, located behind an outer cover plate. Access the connections to the module
by removing the bottom cover of the unit. The RF connections to the amplifier are
BNC for the input and output. Power comes into the module through a 5–pin
header connection next to the RF input jack.
The amplifier is built around two Phillips BLF278 dual-power MOSFETs rated for 50
volts DC and a maximum power of about 300 watts. When biased for class B, the
transistor has a power gain of about 20 dB. (It is biased below class B in the
transmitter.)
Input transformer, T1111, is made up of two printed circuit boards. The four-turn
primary board is separated from the one-turn secondary by a thin dielectric film.
R1112–R1117 are for damping. Trim pot R1111 sets the bias.
Output transformer, T1121, has a one-turn primary on top of the circuit board and a
two-turn secondary underneath. Inductors L1121 and L1122 provide power line
filtering.
4.12
Chassis and AC Supply
AC power supply components are internal to a switching power supply module.
Switching in the power-entry module configures the power transformer for 120 or
240 VAC. See Section 2.2, Power Connections, for switching and fuse information.
Principles of Operation
4—11
Rev A
4.13
RF Output Filter & Reflectometer
The RF low-pass filter/reflectometer are located in the right-hand compartment on
the top of the chassis. See Illustration 6–14 and accompanying schematic for more
information.
A ninth-order, elliptic, low-pass filter attenuates harmonics generated in the power
amplifier. The capacitors for the filter are circuit board pads.
The reflectometer uses printed circuit board traces for micro-strip transmission
lines. Transmission line segments (with an impedance of about 82 ohms) on either
side of a 50–ohm conductor provide sample voltages representative of the square
root of forward and reverse power.
DC voltages, representative of forward and reflected power, go through a bulkhead
filter board to the motherboard, then to the metering board, where they are
processed for power control and metering and for SWR metering and protection.
4.14
Receiver Circuit Board Option
This option allows the transmitter to be used as a translator. The receiver board
receives terrestrially fed RF signal and converts it to composite audio which is then
fed into the exciter board. Microprocessor controlled phase lock loop technology
ensures the received frequency will not drift, and multiple IF stages ensure high
adjacent channel rejection. Refer to illustrations 4–6, 6–16 and its schematic for the
following discussion.
RF In
Receiver
Module
123
123
00
123
00
00
123
45 6
789
456
789
456
789
789
456
00
Illustration 4-5 Receiver Board
The square shaped metal can located on the left side of the receiver board is the
tuner module. The incoming RF signal enters through the BNC connector (top left
corner) and is tuned through the tuner module. Input attenuation is possible with
jumper J1 on the top left corner of the receiver board. Very strong signals can be
attenuated 20 dB automatically by placing the jumper on the left two pins (“LO”
position). An additional 20 dB attenuation is also available with the jumpers in the
top left corner of the board. The frequencies are tuned by setting switches SW1 and
SW2 (upper right corner). These two switches are read upon power up by the
microprocessor (U4). The microprocessor then tunes the synthesizer IC SA1057
4—12
FM250G User’s Manual
Rev A
(U3) to the selected frequency. The switches frequency range is 87.9 Mhz at setting
“00” to 107.9 Mhz at setting “64”. Other custom ranges are available.
The synthesizer chip works on a phase lock loop system. It receives the frequency
information from pin 6 of the tuner module, then goes through a FET buffer
amplifier (Q2) on its way to synthesizer IC (U3). The synthesizer feeds back a DC
voltage through two resistors to pin 4 of the tuner module. Different frequencies
cause different tuning voltages to go to the tuner module to tune it on frequency.
The frequency synthesizer locks on to the exact frequency needed and adjusts the
DC voltage accordingly. The microprocessor tunes the frequencies of the
synthesizer IC, but the DC tuning voltage is somewhat dependent on the tuner
module.
Generally, the voltage is around 0.5 volt DC for tuning 88.1 MHz, and from 5.5 to
6.5 volts DC for tuning 107.9 MHz. The 10.7 MHz IF frequency comes out of the
tuner module on pin 5 and is coupled into the first filter FL1; passes through FL1
and into the IF decoder system of IC LM1865 (U1). The FL1 filter sets the bandwidth
or everything outside of the bandwidth depending on the filter that is selected. It
could be a bandwidth of 180 kHz where everything outside of that is filtered out
depending on the filter characteristics. A second filter (F3) is available when the
signal has a great amount of interference from an adjacent signal. In such a case,
remove the jumper cap that is in the F3 position, then remove the ceramic filter
that is in the F4 storage position and place it into the F3 position.
Then the signal goes to a buffer gain stage at pin 1 of LM1865 (U1). From there the
signal passes through F2, which is a second filter for further removal of unwanted
products, and then it goes on to the IF of that chip. The quadrature coil L4 is tuned
to 10.7 MHz as per calibration procedures. This results in a low distortion of around
0.2 to 0.3% on the audio. The audio, still a composite at this point, will come out of
pin 15 of that IC (U1) and go to the first buffer U9. Then it goes through a
compensation network R54 and C26, and on to the stereo decoder chip at pin 2 of
U5.
When a stereo signal is present, Led 1 illuminates which indicates that left and right
audio is available. Then the stereo signals go to gain stages U6A and U6B and out to
the RCA jacks on the back of the cabinet. These can be used for off-air monitoring of
the audio signal. Incoming frequency can be monitored from the frequency monitor
BNC jack on the back. The stereo buffer U9, stereo decoder U5, and gain stages U6A
and U6B have no effect on the signal that goes through the transmitter. This section
along with the composite signal coming out of pin 15 of LM1865 (U1) is totally
separate from the transmitter section.
A muting circuit, consisting of C22, a 1N914 diode, R14, and variable resistor R15
mutes the output when a signal is too weak to be understood. The strength of the
signal muted is determined by the adjustment of R15. Any signal below the setting
of R15 is shorted to +VCC through C22 by the current drawn through R14 and the
diode. The audio signal above this setting goes through C17 to the connector P3.
The P3 connector block allows jumpering to either internal circuitry or to external
signal processing such as advertisement injection or other forms of altering the
signal. If the jumper is installed for internal circuitry, the signal will go through
R39 to the input of U2A. This is a buffer that drives the R20 pot located on the top
Principles of Operation
4—13
Rev A
left hand corner of the board. R20 sets signal gain for 100% modulation if adjusted
correctly with a full incoming 75 kHz deviation signal. Then the signal goes
through R21, R22, and C20 which, along with adjustable pot R24 and C21, forms a
compensation network with some phase shifting. This allows the best stereo
separation possible by adjusting and compensating for differences in FM exciter
boards. The signal is buffered through U2B and finally reaches the output
connectors P1 and P2, and on to the transmit circuitry.
The power supply is fairly straight forward. The incoming 12 volt supply goes to a
7809, 9 volt regulator (VR1) which supplies all 9–volt needs on the board. The 9
volts also supplies a 7805, 5 volt regulator (VR2) which supplies all 5–volt needs on
the board. Plus and minus 12 volts from the motherboard is filtered and supplies
various needs on the board. Finally there is a precision reference voltage supplied
through R50 by U7 and U8. These two 2.5 volt reference shunts act very much like a
very accurate Zener diode to provide precision 5 volts to the metering board.
4—14
FM250G User’s Manual
Section 5—Adjustments and Tests
This section describes procedures for (1) advanced users who may
be interested in customizing or optimizing the performance of
the transmitter and (2) service personnel who want to return the
transmitter to operational status following a maintenance
procedure.
Adjustments and Tests
5—1
Rev A
5.1
Audio Processor Adjustments
5.1.1
Pre-Emphasis Selection
Select the pre-emphasis curve (75 µsec, 50 µsec, 25 µsec, or Flat) by jumpering the
appropriate pins of header JP1 on the audio processor board. (See Section 2.9,
Audio Monitor Connections.) If you change the pre-emphasis, change the deemphasis jumpers, JP203 and JP204 on the Stereo Generator board, to match. (See
Section 2.8, Composite Input Connection)
5.1.2
Pre-Emphasis Fine Adjustment
Trim potentiometers, R29 and R65, (for left and right channels, respectively)
provide for fine adjustment of the pre-emphasis. Set the potentiometers to bring
the de-emphasized gain at 10 kHz equal to that of 400 Hz. (At the proper setting,
15.0 kHz will be down about 0.7 dB.)
When making these adjustments, it is important that you keep signal levels below
the processor gain-control threshold.
A preferred method is to use a precision de-emphasis network in front of the audio
input. Then, use the non-de-emphasized (flat) output from the FM modulation
monitor for measurements.
5.2
Stereo Generator Adjustments
5.2.1
Separation
Feed a 400–Hz sine wave into one channel for at least 70% modulation. Observe the
classic single-channel composite stereo waveform at TP301 on the RF Exciter
circuit board. Adjust the Separation control for a straight centerline.
Since proper adjustment of this control coincides with best stereo separation, use
an FM monitor to make or confirm the adjustment
5.2.2
Composite Output
You can make adjustments to the composite output in two ways:
• Using a modulation monitor
• Using Bessel nulls
5.2.2.1 Using a Modulation Monitor
1. Set the Stereo-Mono switch to Mono.
2. Check that the setting of the Modulation compensation control ( see Section
2.3.1, Modulation Compensator) on the RF Exciter circuit board, falls within
the range specified for the frequency of operation.
3. Feed a sine wave signal of about 2.5 kHz into the left channel at a level sufficient to put the wideband gain-reduction indicator somewhere in the middle
of its range.
4. Set the Composite level control to produce 90% modulation as indicated on an
FM monitor.
5. Apply pink noise or program material to the audio inputs and confirm, on both
Mono and Stereo, that modulation peaks are between 95% and 100%.
5—2
FM250G User’s Manual
Rev A
5.2.2.2 Using Bessel Nulls
Done properly, the Bessel nulls method provides greater accuracy than the average
modulation monitor. The following procedure sets the gain-control threshold for
90% modulation.
1. Set the Stereo-Mono switch to Mono.
2. Check that the setting of the Modulation compensation control, R351 on the
RF Exciter circuit board, falls within the range specified for the frequency of
operation. (See Section 2.3.1, Modulation Compensator)
3. Feed a 2.807–kHz sine wave signal into the left channel at a level sufficient to
put the wideband gain-reduction indicator somewhere in the middle of its
range. The modulation setting will be only as precise as the frequency of the
sine wave; a 1% error in frequency will result in a 1% error in deviation.
4. Couple a shortwave receiver, tuned to one-tenth the operating frequency (8.70
MHz to 10.80 MHz), to TP302 on the RF Exciter circuit board. (In most cases,
there need not be a direct connection.) The receiver must have either a narrow IF bandwidth setting or a BFO (beat frequency oscillator).
5. Adjust the Composite level control to null the carrier.
a. If using a BFO, set the BFO for a low-frequency audio tone. Listen for this
tone to disappear at the carrier null.
b. Without a BFO, watch the signal-level indicator on the receiver or determine, by ear, the point at which the carrier nulls. (This practice only
works if the bandwidth is narrow enough to discriminate against the 2.8–
kHz sidebands.)
6. Apply pink noise or program material to the audio inputs and confirm, for
both Mono and Stereo, that modulation peaks are between 95% and 100%.
5.2.3
19–kHz Level
Adjust the 19–kHz pilot for 9% modulation as indicated on an FM modulation
monitor.
(The composite output should be set first, since it follows the 19–kHz Level
control.)
5.2.4
19–kHz Phase
1. Apply a 400–Hz audio signal to the left channel for at least 70% modulation.
2. Look at the composite stereo signal at TP301 on the RF Exciter circuit board
with an oscilloscope, expanding the display to view the 19–kHz component on
the horizontal centerline.
3. Switch the audio to the right-channel input. When the 19–kHz Phase is properly adjusted, the amplitude of the 19–kHz will remain constant when switching between left and right.
4. Recheck the separation adjustment as described in Section 5.2.1.
5.3
Frequency Synthesizer Adjustments
5.3.1
Frequency Channel Selections
Refere to Section 2.3, Frequency (Channel) Selection.
Adjustments and Tests
5—3
Rev A
5.3.2
Modulation Compensator
Refere to Section 2.3, Frequency (Channel) Selection.
5.3.3
Frequency Measurement and Adjustment
Next to the 10.24–MHz crystal on the RF Exciter board is a 5.5–18 pF ceramic
trimmer capacitor (C303). Use C303 to set the frequency of the 10.24–MHz crystal
while observing the output frequency of the synthesizer.
Use one of three methods for checking frequency:
• Use an FM frequency monitor.
• Couple a frequency counter of known accuracy to the output of the synthesizer
and observe the operating frequency. Or connect a counter to TP302 and measure one-tenth operating frequency. (Do not connect to the 10.24–MHz clock
circuit.)
• Use a shortwave receiver and test point TP301. This method will, in most
cases, give better accuracy than the first two options. To use this method, follow these steps:
1. Temporarily set the synthesizer to 100.0 MHz.
2. Tune a shortwave receiver to a 10–MHz standard such as WWV or JJY.
3. Loosely couple the receiver to TP302 so that the 10–MHz signal strength from
TP302 is about equal to that being received from the standard station. [In
most cases, setting the receiver (if it’s a portable, such as the Sony® 2010) on
top of the transmitter with the receiver antenna several centimeters (a few
inches) from the TP302 test point, will be about right.]
4. Use the C7 trimmer capacitor to “zero beat” the two signals.
5.3.4
FSK Balance Control
An FSK signal (used for automatic identification of FM repeaters) shifts the
frequencies of the 10.24–MHz crystal reference oscillator and the VCO.
Use an oscilloscope to observe the cathode end of D303. With no program, the pulse
will be less than 1 µsec wide. With an FSK input (a 20–Hz square wave at the FSK
input will work), set trim pot R356 for minimum pulse width.
The setting will vary slightly with operating frequency.
5.4
Metering Board Adjustments
5.4.1
Power Calibrate
While looking at RF Power on the digital panel meter, set the Power Calibrate trim
potentiometer to agree with an external RF power meter.
5.4.2
Power Set
With the front panel RF Output control fully clockwise, adjust the Power Set trim
pot to 10% more than the rated power (275 watts for the FM250ET) as indicated on
an accurate external watt meter. If the authorized power is less than the maximum
watts, you may use the Power Set to limit the range of the RF Output control.
5—4
FM250G User’s Manual
Rev A
5.4.3
SWR Calibrate
When the Carrier switch is off, or the RF power is less than about 5 watts, the SWR
circuit automatically switches to a calibrate-check mode. (See Section 4.5, Metering
Circuit Board, for more information.)
Set the digital panel meter to read SWR. With the Carrier switch off, set the SWR
CAL trim pot to read 1.03.
5.4.4
PA Current Limit
Since it may not be practical to increase the PA current to set the PA Current Limit
control, you may use this indirect method.
With the carrier turned off, look at the DC voltage at the right end of R413 on the
Metering board. The current limit, in amperes, will be 0.35 amps higher than ten
times this voltage. For example, for a current limit of 7.35 amps, adjust the PA
Current Limit control for 0.7 volts at R413 ; or 0.565 volts for 6.0 amps. Set the
current limit for 12 amperes or 1.165 volts.
5.5
Motherboard Adjustments
For Normal-Bypass switch setting, see Section 2.10.
5.6
Display Modulation Calibration
The Modulation Calibrate trim pot sets the sensitivity of the front panel Modulation
bar graph display.
This adjustment may be made only after the Output trim pot on the Stereo
Generator board has been set. (See Section 5.2.4.)
1. Set the Stereo-Mono switch to Mono.
2. Feed a sine wave source of about 2.5 kHz into the left channel at a level sufficient to put the wideband gain-reduction indicator somewhere in the middle
of its range.
3. Set the Modulation Calibrate trim pot so that the “90” light on the front panel
Modulation display just begins to light.
5.7
Voltage Regulator Adjustments
JP701, a 10–pin header on the Voltage Regulator board, sets the time between
program failure and carrier turnoff. Pins 1 and 2 are the two pins closest to the
edge of the board. The times are approximate. See Sections 2.11, 2.12, and 4.8 for
additional information.
1. Short pins 1 and 2 for a 30–second delay.
2. Short pins 3 and 4 for a 2–minute delay.
3. Short pins 5 and 6 for a 4–minute delay.
4. Short pins 7 and 8 for an 8–minute delay.
You may select other times by changing the value of R721. The time is proportional
to the resistance.
Adjustments and Tests
5—5
Rev A
5.8
Performance Verification
Measure the following parameters to receive a comprehensive characterization of
transmitter performance:
•
•
•
•
•
•
•
•
•
•
•
Carrier frequency
RF output power
RF bandwidth and RF harmonics (see section 5.11)
Pilot frequency, phase, and modulation percentage
Audio frequency response
Audio distortion
Modulation percentage
FM and AM noise
Stereo separation between left and right
Crosstalk between main channel and subcarrier
38–kHz subcarrier suppression
In addition to the above tests, which pertain to signal quality, a complete check of
the unit will include items listed in 5.20.
5.8.1
Audio Proof-of-Performance Measurements
References to “100%” modulation assume 9% pilot and 91% for the remainder of
the composite stereo signal.
Because the audio processing threshold is at 90% modulation, it is not possible to
make audio proof-of-performance measurements at 100% modulation through the
audio processor. Instead, audio data for 100% modulation is taken from the input of
the stereo generator (SW501 on Motherboard set for Bypass). Then, data, including
the audio processor (SW501 set for Normal), is taken at a level below the audio
processing threshold.
5.8.2
De-emphasis Input Network
A precision de-emphasis network, connected between the test oscillator and the
audio input of the transmitter, can be very helpful when making the audio
measurements. Note that the input impedance of the transmitter or the source
impedance of the test oscillator can affect network accuracy. With the de-emphasis
network, oscillator level adjustments need only accommodate gain errors, instead of
the whole pre-emphasis curve.
5.9
Carrier Frequency
Carrier frequency is measured at the output frequency with a frequency monitor or
suitable frequency counter.
To adjust frequency, see 5.3.3. (FCC tolerance +/– 2000 Hz per FCC Part 73.1540
and 73.1545.)
5.10
Output Power
The output power reading on the front panel display should be 90–105% of the
actual value. For a more precise measurement, use a watt meter in the RF output
line. See sections 5.4.1 and 5.4.2 for setting power.
5—6
FM250G User’s Manual
Rev A
5.11
RF Bandwidth and RF Harmonics
You can observe RF bandwidth and spurious emissions with an RF spectrum
analyzer.
In the Stereo mode, feed a 15.0–kHz audio signal into one channel to provide 85%
modulation as indicated on a monitor. Doing so produces 38% main, 38% stereo
subcarrier, and 9% pilot per FCC Part 2.1049. As an alternative, use pink noise into
one channel.
Using a spectrum analyzer, verify the following (per FCC 73.317):
1. Emissions more than 600 kHz from the carrier are at least 43 + 10log(power,
in watts) dB down (58 dB for 30 watts, 63 dB for 100 watts, 67 dB for 250
watts). The scan should include the tenth harmonic.
2. Emissions between 240 kHz and 600 kHz from the carrier are down at least 35
dB.
3. Emissions between 120 kHz and 240 kHz from the carrier are down at least 25
dB.
5.12
Pilot Frequency
The pilot frequency should be within 2 Hz of 19 kHz. (FCC Part 73.322.) Using a
frequency counter, measure 1.9 MHz at pin 1 of U209 on the Stereo Generator
board. A 200–Hz error here corresponds to a 2–Hz error at 19 kHz. If the frequency
is off by more than 50 Hz, you may change the value of C213. (Changing C213 from
56 pF to 68 pF lowers the 1.9 MHz by about 35 Hz.)
5.13
Audio Frequency Response
For the response tests, take the readings from an FM modulation monitor.
Make audio frequency response measurements for left and right channels at
frequencies of 50 Hz, 100 Hz, 400 Hz, 1 kHz, 5 kHz, 10 kHz, and 15 kHz. See
Sections 5.8.1 and 5.8.2.
5.14
Audio Distortion
Make distortion measurements from the de-emphasized output of an FM
modulation monitor.
Make audio distortion measurements for left and right channels at frequencies of 50
Hz, 100 Hz, 400 Hz, 1 kHz, 5 kHz, 10 kHz, and 15 kHz. See Sections 5.8.1 and 5.8.2.
5.15
Modulation Percentage
While feeding an audio signal into the left channel only, confirm that the total
modulation percentage remains constant when switching between Mono and
Stereo.
Measure modulation percentage with an FM modulation monitor, or by using an HF
receiver and Bessel nulls. See Section 5.2.2.
19–kHz pilot modulation should be 9%.
5.16
FM and AM Noise
Take noise readings from a de-emphasized output of a modulation monitor.
Adjustments and Tests
5—7
Rev A
5.17
Stereo Separation
Make left-into-right and right-into-left stereo separation measurements with an FM
modulation monitor for frequencies of 50 Hz, 100 Hz, 400 Hz, 1 kHz, 5 kHz, 10
kHz, and 15 kHz.
5.18
Crosstalk
For stereo crosstalk measurements, both left and right channels are fed at the same
time. For best results, there needs to be a means of correcting small imbalances in
levels and phase. The balance is made at 400 Hz.
5.18.1
Main Channel Into Sub
Feed the left and right channels in phase with audio (L+R) at 50 Hz, 100 Hz, 400 Hz,
1 kHz, 5 kHz, 10 kHz, and 15 kHz at 100% modulation, while observing the stereo
subcarrier (L-R) level on an FM modulation monitor.
5.18.2
Sub Channel Into Main
Feed the audio into the left and right channel as above, with the exception of
reversing the polarity of the audio of one channel (L-R input). Using the
frequencies of 5.18.1 above, observe the main channel (L+R) level with a
modulation monitor.
5.19
38–kHz Subcarrier Suppression
With no modulation, but in the Stereo mode, the 38–kHz subcarrier, as indicated on
an FM modulation monitor, should be down at least 40 dB.
5.20
Additional Checks
In addition to the tests and adjustments mentioned in this section, the following
checks ensure a complete performance appraisal of the transmitter:
1. Perform a physical inspection, looking for visible damage and checking that
the chassis hardware and circuit boards are secure.
2. Check the functionality of switches and processing control.
3. Verify that all indicators function.
4. Check the frequency synthesizer lock at 80 MHz and 110 MHz.
5. Measure the AC line current with and without the carrier on.
6. Perform a functional test of the SCA input, Monitor outputs, and the monitor
and control function at the 15–pin, D-sub connector.
7. Test the functionality of the FSK circuit.
8. Check the operation and timing of the automatic carrier-off circuitry associated with program failure.
9. Check all metering functions.
10. Test ALC action with PA current overload, SWR, and PLL lock.
Note: FCC type acceptance procedures call for testing the carrier frequency
over the temperature range of 0–50 degrees centigrade, and at line
voltages from 85% to 115% of rating. (See FCC Part 2.1055.)
5—8
FM250G User’s Manual
Section 6—Reference Drawings
The illustrations in this section may be useful for making
adjustments, taking measurements, troubleshooting, or
understanding the circuitry of your transmitter.
Reference Drawings
6—1
Rev A
6.1
Views
Gain
Reduction/Expansion Digital
Multimeter
Indicators
Multimeter Select
Modulation
Indicators
10
2
High Band
RF Power
High
Expand
2
Compress
SWR
20
ALC
PA DC Volts
Wide Band
PA DC Amps
-6
SWR
Over
Lock
100
Input
90
PA DC
80
PA Temp
70
60
PA Temperature
+6 dB
+12 dB
Carrier
Power
50
Supply DC Volts
-12
Modulation
Fault
Audio Input
Carrier
Switch
Stereo
Voltmeter
40
30
-18
20
Low
Pilot
Input Gain
Processing
Mono
RF Output
FM BROADCAST TRANSMITTER
Processing Stereo/Mono
Relative RF Power
Audio Processor
Control
Voltage Out Switch
Switch
Input Level
Input
Gain
Fault
Indicators
Indicators
Switches
Illustration 6-1 Transmitter Front View
RF
Output
RF Output
Monitor
Composite
Input
SCA IN
Audio Monitors Audio Inputs
MONITOR
COMPOSITE IN
R
RIGHT
LEFT/MONO
L
REMOTE I/O
1
2
3
FUSE
AC Power In
SCA Inputs
Power Amplifier and Cooling
Remote I/O
Illustration 6-2 Transmitter Back View
6—2
FM250G User’s Manual
Rev A
RF Output
Power Amplifier and Cooling
Stereo
Generator
RF Exciter
RF Output (Lowpass) Filter and
Reflectometer
Audio
Processor
Metering
Display
Illustration 6-3 Chassis Top View
AC Power
Entry
RF Predriver/Amplifier
AC Power Supply
Power Regulator
Voltage Regulator
Illustration 6-4 Chassis Bottom View
Reference Drawings
6—3
Rev A
6.2
Board Layouts and Schematics
Illustration 6-5 Audio Processor Board
6—4
FM250G User’s Manual
Rev A
R9 1K
L VU
C3
1.0
R2
1K
L IN1
R4
24.9K
1
R6
24.9K
1
+12V
C1
100PF
L IN2
R8
30.1K
1
C4
1.0
L LP2
7
5
1
X
3
Y
+5V
16
R11
47K
8
3
R VU
R IN1
R42
24.9K
7
8
C18
.047
2
U4A
TL072
C13
100PF
R IN2
C16
1.0
R41
1K
2
R43
24.9K
1
3
7
9
4
1
C14
100PF
R45
24.9K
6
2
U6
13
12
-12V
R67
24.9K
10
11
D8
R58
11.3K
1
3
D7
C20
1.0
POLY
PRE-EMP.
R123
50K
3
R53
499
1
-12V
11
2
3
10K
2
3
6
VO
IN
U17
4
GND
U18A
TL072
C38
1.0
5
TRM
+5V
C46
0.1
R121
10.0K
1
7
7
VSS
-5V
C39
1.0
8
7
6
5
8 C1
7 B2
6 E3
5
4
1
2
3
4
D13
C41
1.0
C48
0.1
8
2
RECEPT 10X2
J2
L LP1
L LP2
R LP1
R LP2
R OUT
L OUT
10
8
6
4
2
RECEPT 5X2
9
7
5
3
1
R105
1M
8
R101
10K
D16
2
1
3
U14A
TL072
1K
4
R106
1K
R76
10K
C30
1.0
D15
D14
YEL
4
C35
1.0
D17
D18
560
TEST
.25V/DB
R99
Q3
R77
3.3K
2N5210
R107
10K
-12V
D21
-12V
3.3K
-5V
R111
49.9K
1
J3
J1
2
4
6
8
10
12
14
16
18
20
3mV/DB
R100
120
D20
C25
100PF
L IN1
L IN2
R IN1
R IN2
8
7
6
5
R93
10K
R92
3
1 C8
2 B7
3 E6
4
5
C20A
OPEN
-12V
1
3
5
7
9
11
13
15
17
19
R91
10M
1
C45
0.1
-12V
C32
100PF
R96
20.0K
1
1
2
3
4
R75
2.4K
C8A
OPEN
2
4
6
8
R104
OPEN
R97
49.9K
1
+12V
3mV/DB
R80
3.3K
C43
0.1
1
3
5
7
+12V
U13A
TL072
C44
0.1
C42
0.1
R103
3.3K
C34
OPEN
R95
20.0K
1
Q7
LM394
+12V
C40
1.0
JP1
HEADER 4X2
FLAT
25uS
50uS
75uS
6
R82
120
+12V
POT LOCATED
ON DISPLAY PCB
4
R79
49.9K
1
-5V
5
U18B
TL072
C33
.047
R94
20.0K
1
PROC C
Q5
LM394
C37
.01
6
D12
R109
3.3K
C26
100PF
VEE
R122
100
SW1B
5
C47
0.1
R78
91K
R118
10.0K
1
D11
C49
47PF
R650
100K
R86
3.3M
C28
1.0
POLY
-12V
REF02
4
+5V
R120
100
4
LIGHT
+5V
VDD
1
1
+5V
+5.00V
8
2
U12A
TL072
-12V
PROC B
R89
330K
D19
C36
.01
8
3
PROC A
R88
10M
R83
+12V
+12V
2
-12V
HEAVY
R85
3.3K
-5VDC at 0DB GR
4.1V at 20 DB GR
U10A
4 TL072
R68
12K
R69
10K
-5V
C27
.047
R73
24.9K
R72
24.9K
1
-12V
C29
0.1
R87
3.3K
SW1A
8
2
R90
1K
TL072
1
R119
4.7K
3
1
-12V
C50
47PF
-5V
3
10
R66
49.9K
1
8
+12V
R81
1K
2
U9
Q2
2N5087
2
C22
.0027
POLY
1
13
12
R65
10K
U7A
R OUT
R71
240K
D10
7
9
R61
24.9K
+12V
R74
1K
C23
220PF
14 AD632
R64
OPEN
-12V
C24
0.1
R70
24.9K
+12V
R62
100K
R60
24.9K
4
U2B
TL072
D6
D5
D9
5
U2A
TL072
R33
10K
(+/-5.0V PK)
R52
499
1
7
4
U12B
TL072
7
6
5
+5V
R51
1.0K
1
8
U10B
TL072
-12V
R59
100K
1
14 AD632
R50
2.0K
1
R47
30.1K
1
R32
12K
R37
24.9K
+12V
1
3
R46
360K
R44
24.9K
R30
49.9K
1
7
5
3
D4
R36
24.9K
6
10
11
U7B
TL072
R LP1
+12V
13
12
L OUT
R35
240K
-5V
R39
1K
2
U8
D3
R38
1K
+12V
C17
.047
1K
C15
1.0
R40
1K
R29
10K
R25
24.9K
1
C10
.0027
POLY
1
5
R LP2
1
R28
OPEN
Q1
2N5087
C12
0.1
1
C11
220PF
1 4 AD632
7
9
PRE-EMP.
D1
6
R98
100
20K
R31
24.9K
1
+12V
R26
100K
R24
24.9K
1
-12V
R49
R48
D2
R22
11.3K
1
R56
75K
1
74HC4052
/+12DB
/+6DB
R17
360K
R16
499
1
1
5
2
4
6
10
9
Y0
Y1
Y2
Y3
INH
A
B
7
-5V
12
14
15
11
R34
24.9K
10
C8
1.0
POLY
R15
499
1
X0
X1
X2
X3
1
2
R14
1.0K
1
U3
13
FLAT A=0
25uSEC A=0.33
50uSEC A=0.67
75uSEC A=1.0
(+/-5.0V PK)
11
C6
.047
R13
2.0K
1
R12
20K
1
R10
47K
5
R23
100K
U5
13
12
7
R1
100
-12V
+5V
7
9
6
U1A
TL072
4
+5V
AD632
14
U4B
TL072
L LP1
1
3
GAIN: U5, Pin 2 to U8, Pin 2
(No Hi-band gain reduction)
+12V
2
R7
24.9K
1
C2
100PF
R20
75K
1
C5
.047
6
8
R5
24.9K
1
R3
1K
U1B
TL072
GAIN REDUCTION VOLTS P-P
THRESHOLD
1.1
10DB
3.5
20DB
11
1
3
5
7
9
11
13
15
17
19
21
23
25
2
4
6
8
10
12
14
16
18
20
22
24
26
+12V
-12V
/+6DB
/+12DB
L VU
R VU
+5.00V
PROC A
PROC B
PROC C
BR GR
HI GR
TEST
R112
49.9K
1
C31
100PF
R115
49.9K
1
+12V
8
2
6
7
6
1
5
U13B
TL072
5
U15B
TL072
R113
100
R84
49.9K
1
6
8
.25V / DB
BR GR
6
7
5
U14B
TL072
U15A
TL072
1
-12V
R110
49.9K
1
NOTES :
1. ALL RESISTORS ARE IN OHMS, 1/4W, 5% UNLESS OTHERWISE SPECIFIED.
U16B
TL072
R117
100
0.25V / DB
HI GR
3
7
5
4
+12V
2
3
7
R116
49.9K
1
R102
49.9K
1
R114
49.9K
1
4
-12V
U16A
TL072
SCM, FM AUDIO PROCESSOR
103202
2. ALL CAPACITORS ARE IN MICROFARADS UNLESS OTHERWISE SPECIFIED.
RECEPT 13X2
3. ALL DIODES ARE 1N4148 UNLESS OTHERWISE SPECIFIED.
Schematic 6–1 Audio Processor
6-5
Rev A
Illustration 6-6 Stereo Generator Board
6-6
FM250G User’s Manual
Rev A
24.9K
EXT IN
1%
3
C5
.0027
POLY
15.2 KHz LOW-PASS FILTER
(8th ORDER ELLIPTICAL)
LTC1064-1
1
2
3
4
5
6
7
LPIN L
+6V
U1
R7
3.65K
1%
-6V
R1
330
R38
1M
2
8
R5
1K
R12
10.0K
1%
U3A
TL072
1
3
C6
1030PF
R9
2K 1%
+12V
4
R6
499
1%
LPOUT L
C1
.0027
POLY
C4
0 OHM
+12V
2
14
13
12
11
10
9
8
D4
C3
100PF
R3
0 OHM
3
D3
C27
1.0
-12V
(3.5V P-P for 7.5KHz)
SCA IN
JP1
1
INPUT L
U6A
TL072
4
R57
24.9K
-12V
1
C9
.0027 POLY
8
2
R10
2.49K 1%
R8
4.99K 1%
4
U4A
TL072
JP3
75
U5
74HC4053
D5
-12V
1
2
3
4
5
6
7
LPIN R
U2
1
INPUT R
C7
.01 POLY
3
2
14
13
12
11
10
9
8
R19
3.65K 1%
R2
330
R39
1M
7
5
R22
2.49K
1%
R20
4.99K
1%
7
C23
1.0
D1
1N5818
3
2
50
D2
1N5818
+5.00V
U4B
TL072
75
14
R28
243K 1%
1
+6V
2
3
U10A
R204
1K
R33
10.0K 1%
1.52 MHz
R27
100
C29
1.0
5
R23
24.9K
R37
1K
R29
100K 1%
R25
1M
3.8 MHz
Y1
7.6MHZ
2
1
C13
56PF
NPO
C12
5.5 18PF
C14
33PF
NPO
13
U7F
14
7
U7A
74HC04
U8A
74HC390
12
1
4
2
CKA
CKB
CLR
1
0
16
QA
QB
QC
QD
15
12
3
5
6
7
CKA
CKB
14
13
11
10
9
QA
QB
QC
QD
CLR
U9B
74HC393
13
8
U8B
74HC390
12
304 Khz
A
11
10
9
8
QA
QB
QC
QD
CLR
CLK
QA
QA
QB
QC
QD
4
3
S
1
A
I
N
V
A
H
P
A
B
P
A
L
P
A
S
1
B
I
N
V
B
H
P
B
B
P
B
L
P
B
1
7
1
8
1
9
R48
4.3K
J1
10
11
-12V
R32
10K
R47
20K
CLR
9
2
8
U10C
R36
49.9K
1%
13
QC
11
U10D
R35
10.0K 1%
U7B
74HC04
+12V
U7C
74HC04
9
VR1
LM317
1
+12V
OUT
IN
+6V
3
C
C33
1.0UF
6
R49
240
2
R244 10K
C34
1.0UF
1718 WEST MISHAWAKA ROAD
STEREO
VR2
LM337
1
-12V
C35
1.0
IN
OUT
C
X
ELKHART, IN. 46517
PHONE (219) 294-8000
Z1
U5X
C36
47UF
MONO
JFL
7-28-97
JB
1
ME
SUPERSEDES
SCALE
NONE
EE
E.C.
PROJ #
MLOWCM0
PE
DRAWN
CHECKED
B
-6V
3
R51
240
2
+5.00V
X1
X0
-12V
LPIN L
LPOUT L
LPIN R
LPOUT R
+5.00V
SYNC OUT
SCM, FM STEREO GENERATOR
U5Y
10
GND
RECEPT 12X1
CROWN INTERNATIONAL, INC.
U205 Connections
U7E
74HC04
11
NOTES :
_______
_______
MON L
MON R
-6V
R50
910
8
19 KHz
3.3VP-P
1. ALL RESISTORS ARE IN OHMS, 1/4W, 5% UNLESS OTHERWISE SPECIFIED.
2. ALL CAPACITORS ARE IN MICROFARADS UNLESSOTHERWISE SPECIFIED.
3. ALL DIODES ARE 1N4148 UNLESS OTHERWISE SPECIFIED.
EXTERNAL COMPOSITE
U7D
74HC04
QB XOR QD
QC XOR QD
C20
.0027
POLY
C32
1.0
4
R43
33K
R41
510
C19
0.1
R31
100K
1%
1
2
3
4
5
6
7
8
9
10
11
12
19 KHZ LEVEL
19 KHZ PHASE
C16 0.1
7
QD
EXT IN
EXT RTN
SCA IN
COMP OUT
COMP METER
MONO/STEREO
/EXT ENABLE
GND
INPUT L
INPUT R
J2
R242 1K
5
SEPARATION
2
0
R30
243K
1%
74HC86
12
3
1
2
3
4
5
6
7
8
9
10
11
12
3
R46
10K
C21
0.1
9
7
5
3
1
RECEPT 5X2
1
13
12
R40
10K
U11
LMF100
1
6
7
9
2
C18
.0027
POLY
1
2
-12V
+12V
RECEPT 12X1
A
10
QA XOR QC
Current at U211 pin 17.
1 1 1 1
2 3 4 5
5
J3
10
8
6
4
2
1
QB
Current at U211 pin 4.
1
1
1.9MHz
U9A
74HC393
3
4
5
6
5
0
/
A
1 V V G
0 D A N
0 - - D
C
L
K
B
7
9 8 7 6
L V V S
S D A A
H + + /
B
C
L
K
A
14
7.6 MHz
QB XOR QC
R34
49.9K
1%
1%
U12
B-B 4214
14
38 KHz
3.0VP-P
COMP METER
C37
OPEN
+12V
6
U10B
R17
100
-6V
R13
24.9K 1%
4
R26
1K
7
8
SYNC OUT
C17
0.1
COMP OUT
( 3.85V P-P)
U6B
TL072
R21
10K
C31
1.0
C15
0.1
7
INH
A
B
C
/EXT ENABLE
+6V
R16
100
6
4
5
R53
10K
C11
.01 POLY
C30
1.0
74HC86
+6V
Z
Z0
Z1
9
JP4
15
Y0
Y1
6
11
10
MONO/STEREO
MON R
5
1
C24
1.0
R24
100
6
14
Y
5
3
C10
1030PF
X
X0
X1
2
1
D6
U3B
TL072
R18
499
1%
LPOUT R
C2
.0027
POLY
6
R15 (SELECTABLE BY TEST, USE
4.12K OR 4.15K IF NEEDED)
4.02K
1%
R14 1K
16
12
13
JP2
LTC1064-1
OUTPUT
C28
1.0
MON L
3
3
2
50
+6V
R11
100
1
U206, pin6
Z0
Y
Y0
C
/EXT EN
FILENAME:
STEREO/MONO
A
DO NOT SCALE PRINT
U5Z
Z
Y1
APPROVED BY :
103203A.SCM
NEXT ASM:
DWG. NO.
REV
103203
A
R52
910
Schematic 6–2 Stereo Generator
6-7
SEE NOTE 10
TOP SIDE COMPONENT MAP, FM-VFM EXCITER
UNCONTROLLED
UNLESS OTHERWISE MARKED IN RED BY CM AS A
CONTROLLED COPY, COPIES OF THESE DOCUMENTS AND
ASSOCIATED ELECTRONIC FILES ARE UNCONTROLLED AND
ARE FOR REFERENCE ONLY.
THESE DRAWINGS, SPECIFICATIONS AND ASSOCIATED
ELECTRONIC FILES ARE THE PROPERTY OF INTERNATIONAL
RADIO AND ELECTRONICS CORP., AND SHALL NOT BE REPRODUCED,
COPIED, OR USED AS THE BASIS FOR THE MANUFACTURE OR SALE OF
APPARATUS OR DEVICES WITHOUT PERMISSION.
M200440PT-A.DOC
PWB: 200440-PWB-A.PCB
SIZE DWG. NO.
B
SCALE:
N/A
REV
200440-PWA
PROJECT #:
509
A
SHEET:
1 OF 1
1
2
3
4
5
DWG. NO.
6
REV.
200440-SCH
A
8
9
E . C . N.
10
11
REVISION HISTORY
DESCRIPTION
REV
12
DATE
DWN
1
FOR PROTOTYPE
01-04-02
DW
2
MODIFIED PER MIKE SENEKI
02-06-02
DW
3
CHG'D R18 PER EAD MRH01. R18 WAS 91K OHM. U5 WAS C 6900-5
06-24-02
DW
246 A-G
4
R8 WAS 1.0K OHM.
05-23-03
DW
277
A
PRODUCTION RELEASE
01-29-04
DW
H
APPROVALS
CHK
CM
PE
H
DW
DP
88-108 MHZ
+8V
+12V
R24
150
+12V
2
MAR-6
C7
.001
R30
10 1
VU5
3
/LOCK
DL1
GREEN
R25
680
+5V
5
37
R33
100
1%
13
12
FSK-R
C1
33PF NPO
C11
C4
1
.001
C13
3900PF
R11
100K
1%
8
U5C
10
R10
100K
1%
MC33284P
13
12
7
9
TP
RA2
RA3
RTC
CLR
VSS
RB0
RB1
RB2
RB3
R1
10.0K
1%
10
9
8
7
6
5
4
3
2
1
D
D2
1N4148
LOAD
DATA
CLK
RP1
100K RPACK
1
2
3
4
5
6
7
8
9
10
9
8
7
6
5
4
3
2
1
R3
150K
18
17
16
15
14
13
12
11
10
RA1
RA0
OSC1
OSC2
VDD
RB7
RB6
RB5
RB4
R13
100K
1%
5
D7
1N4148
+ C27
10/35V
D8
1N4148
C28
R63
39
+8V
R81
10.0K
1%
3
C76
0.1
JP1
JUMPER
C81
1000pF
1
U8A
TL072
2
R83
5.11K 1%
6
5
C78 0.1
E
R84
5.11K 1%
-12V
D5 1N4148
U8B
TL072
7
S
G
Q72
IRFD9120
D
D13
3.9V
+12V
1
PB1
RESET
47/20V
C77
0.1
R80
24.3K 1%
F
TANT.
R14
100K
1%
C5
.001 POLY
R21
100K
1%
C26
.001
+ C61
R65
100K
1%
TANT.
U3
PIC16C61
8
U5B
MC33284P
POLY
9
R20
R18
68K
VU5
U5A
3
1
R82
24.3K 1%
C80
0.1
TP2
-12V
4.5 - 8.0V
680.0
11
MC33284P
D
R87
10K
PWR. CNTRL TILT
R86
C43
1
2
D4
1N4148
RP2
100K RPACK
R89
26.7K 1%
1M
4
QH
CLK
QH
INH
SH/LD
2
15
1
7
CLK
QH
INH
SH/LD
SER
A
B
C
D
E
F
G
H
10
11
12
13
14
3
4
5
6
10
11
12
13
14
3
4
5
6
D1
1N4148
6
7
RF OUT
2
R67
15
1%
R15
100K
1%
A1
C24
33pF NPO
R62
100
1%
C62
220pF
MAR-6
1
R66
150
R64 4.99K
VDD
R2
10.0K
1%
R39
100
1%
C23
.001
VCO61
POS-150
R61
10.0K
1%
C15
0.01
+5V
+5V
U2
74HC165
2
15
1
QH
SER
A
B
C
D
E
F
G
H
9
7
5
3
1
10
8
6
4
2
HEADER 5X2
E
9
U1
74HC165
U5D
R16
100K
1%
D12
1N4148
DATA
HD1
14
C14
.001 POLY
/ENABLE
+5V
R12
1.0K
1%
MC33284P
R8
100
1%
CLOCK
C82
.01
POLY
9
R6
100K
1%
U4E
74HC14
7
5
3
1
R7 10
MC145170
C3
1-10PF
C2
39PF NPO
VDD
C10
.001
C19
.001
1
10.24MHZ
Y1
16
15
14
13
12
11
10
9
16
15
14
13
12
11
10
9
R26
680
3
R4 100K 1%
F
1
2
3
4
5
6
7
8
U4F
74HC14
DL2
RED
LOCK
10
4
1
2
3
Fin 4
5
6
7
8
R38
15
TANT.
8
6
4
2
U6
OSC in
OSC out
11
8
R5
1.0K
1%
C12
1
G
C22
.001
D11
1N4148
+ C21
R88
30.1K 1%
REMOTE FREQUENCY CONTROL
R9
100K
1%
R35 499K
1%
10/35V
C8
1
D6
1N4148
+8V
6
NE5532
VVCO
9
7
5
3
1
LOCK DET.
10
8
6
4
2
PL1
HEADER 5X2
U7B
NE5532
C9
.001
R23
1M
R22
200K
R68
499K
1%
2
U7A
4
G
+5V
2
GND
DATA
CLOCK
LOAD
+5V
1
A2
C44
1
8
C6
100PF
5
4
3
2
1
5
4
3
2
1
SW3
SW4
SW5
C29
1
R90
5
4
3
2
1
SW2
SW1
R19
25K
LF SEP.
+ C30
R17
1K BECKMAN
TP1
10/35V
499 1%
5
4
3
2
1
5
4
3
2
1
C79 0.1
R85
2K
PWR. CNTRL. OFFSET
D14
6.2V 1N753A
TANT.
VR3
LM317
COMPOSITE IN
C41
100PF
+12V
3
R27 10.0K 1%
U4B
74HC14
4
U4A
74HC14
3
2
10/35V
1
R43
1.0K
1%
9
8
5
6
U4D
74HC14
U4C
74HC14
-12V
+12V
Local/Remote
/LOCK
LOCK
FSK-ID-CHAN
C31
.001
C33
33pF
VR2
LM78L05
FSK-R
3
-12V
R45
10K
FSK
+12V
C35
.001
D10
1N4148
THESE DRAWINGS AND SPECIFICATIONS ARE THE
PROPERTY OF INTERNATIONAL RADIO CORP.
AND SHALL NOT BE REPRODUCED, COPIED OR USED AS
THE BASIS FOR THE MANUFACTURE OR SALE OF APPARATUS OR
DEVICES WITHOUT PERMISSION.
UNCONTROLLED
UNLESS OTHERWISE MARKED IN RED INK BY CM AS A
CONTROLLED COPY, COPIES OF THESE DOCUMENTS
INCLUDING ASSOCIATED ELECTRONIC REPRODUCTIONS
ARE FOR REFERENCE ONLY.
C_L_SHT1_A.DOT REV. A
5
6
7
8
DWN
CHK
CM
PE
DW
01-04-02
DJ
01-05-02
DW
01-05-02
DP
01-05-02
INTERNATIONAL RADIO AND ELECTRONICS CORP.
25166 LEER DRIVE ELKHART, IN. 46514
574-262-8900
WWW.IREC1.COM
TITLE:
SIZE
DISTRIBUTION
9
B
IREC
SCH, FM-VFM RF EXCITER
DWG . NO .
C
K
FILENAME:
C16, C17, C18, C20, C25, C34, C45-60, C63-75,
Q1-71, R29, R31, R32, R34, R36, R37, R49, R50,
R53-60, R69-79, VCO1-VCO60.
C40
1
TANT.
APPROVALS
BAND LIMIT
A
4
+ C39
FSK BAL.
ID
3
+5V
10/35V
AUTO ID
2
REFERENCE DESIGNATORS NOT USED:
1
R46
39K
CH. SEL.
DIRECT FSK
1
OUT
D3
1N4148
GND
GND
RECEPT 13X2
IN
C
C42
.001
R48
1.0K
1%
NOTES :
1. ALL RESISTORS ARE IN OHMS,
1/4W, 5% TOL.
2. ALL CAPACITORS ARE IN MICROFARADS.
2
2
4
6
8
10
R44
10.0K
1%
HD2
HEADER 5X2
1
3
5
7
9
COMPOSITE IN
Frequency Select
TANT.
UNLESS OTHERWISE SPECIFIED:
J1
RF OUT
+ C38
D9
1N4148
C32
.001
Local/Remote
C
10/35V
TANT.
R47
1.0K
1%
+8V
R52
1.27K
1%
10/35V
R40 10.0K 1%
25
23
21
19
17
15
13
11
9
7
5
3
1
R51
237
1%
TANT.
R41 10.0K 1%
+5V
8.26V
1
+ C37
FSK
26
24
22
20
18
16
14
12
10
8
6
4
2
OUT
+ C36
DL3
AMBER
R28 10.0K 1%
R42 10.0K 1%
B
IN
C
+5V
2
C
SCALE :
10
NONE
A
REV
A
200440-SCH
PROJ NO.
11
509
SHEET
1
12
OF
1
D 8169-1
Rev A
Illustration 6-8 RF Metering Board
6-10
FM250G User’s Manual
Rev A
+12V
PAV
J2-4
C401
.01
R406
100K 1
Parts not loaded:
8
2
+5.00V
U2
1
J4-3
REM PADCV
1.00V = 10VDC
3
C403, 404
DZ401
R402, 403, 404
Q401, 402
U401
LB401
R401
1N4148
D406
R409
100
4
-12V
R410
100
5
(Jumper under board)
C406
.01
R405
2.49K 1
J402
13
12
R416
100K
R425
1M
U405F
74HC14
U3
3
50mv per degree C.
R422
75k
R420
100K 1
C407
.001
8
J4-6
REM PATEMP
C408
1.0UF
J3-12
U403D
TL074
R437
1M
+12V
/LOCK
J4-1
D403
3
R436
24.9K
11
D411
/+28V INH
D410
J2-1
6
INPUT LAMP
J3-16
U405C
74HC14
R439
100K
U404A
TL074
SEL A
SEL B
SEL C
RF LEVEL
+5.00V
PATEMP LAMP
PADC LAMP
INPUT LAMP
LOCK LAMP
SWR LAMP
LOCK LAMP
J3-18
4
5
INPUT
J2-12
1
R435
100K
3
C409
.001
U4
4
2
10mV/Deg. C
R419
24.9K
RECEPT 12X1
U405B
74HC14
R428
10K
-12V
2
4
6
8
10
12
14
16
18
20
1
3
5
7
9
11
13
15
17
19
(R435+R436)+R436
---------------- = ---(R435+R436)-R436
SWR LIMIT=
150K
R440
33K
R434
10K POT H
= 1.5:1
100K
-12V
POWER SET
9
R441
1M
R443
51K
C410
0.1
U4
R442
51K
D404
8
DC SUPPLY
J2-2
R445
R451
100K 1
U4
6
7
U403B
TL074
R452
10K 1
ALC
J4-2
5
R444
200K
U404B
TL074
J4
RECEPT 12X1
R448
100K 1
REM BATT
J4-7
5
C412
0.1
R447
1K
7
U404C
TL074
R454
100
U3
6
FAULT SUM
REM BATT
REM PATEMP
REM RFWATTS
REM PADCA
REM PADCV
ALC
/LOCK
100K
10
12
11
10
9
8
7
6
5
4
3
2
1
GND
R446
10K
C411
0.1
J3
DPM REF
DPM IN
J404
+5.00V
D405
+5.00V
HEADER 10X2
D412
R438
120K
RF LEVEL
J3-8
J2
HD403
D409
R492
10K
FAN
J2-7
12
PAV
PAI
DC SUPPLY
/+28V INH
PATEMP LAMP
U405A
74HC14
R431
120K
R430
100K
FAULT SUM
J4-8
12
11
10
9
8
7
6
5
4
3
2
1
+5V
R432
100K
14
R427
240K
5.00V = 100 deg. C
C431
0.1
U3
13
R426
30.1K 1
10
U403C
TL074
10
2
D402
-12V
R423
240K
R421
100
11
U405E
74HC14
R429
220K
U403A
TL074
11
R424
100k
-12V
U3
9
D408
R415
120K
1
INPUT
RF REV
RF FWD
RFV
VOLTMETER
FAN
TEMP OUT
PADC LAMP
J3-14
+12V
4
-12V
+12V
RECEPT 5X2
D401
1
C421
.001
TEMP OUT
J2-6
13
9
7
5
3
1
+5V
C405
.001
U4
U404D
TL074
2
-12V
+12V
SWR LAMP
J3-20
D407
R413
33K
14
R407
10.0K 1
10
8
6
4
2
U405D
74HC14
12
R408
1.1K 1
R418
1K
R414
2.2M
J4-4
REM PADCA
1.00V = 10.0A
U402B
TL072
J401
+5V
8
9
R412
10K POT H
7
PAI
J2-3
PAI LIMIT
U402A
TL072
6
R450
10K
U5
R411
15K
-12V
R449
11K 1
+5V
(1.999V reads "1999")
FULL SCALE
16
RF POWER (RFV SQUARED)
.001V per Watt
R453
RF POWER
SWR
ALC
PA DCV
PA DCI
PA TEMPERATURE
SUPPLY DC VOLTS
VOLTMETER
1.1K 1
10mV/Volt
100mV/Amp
1mV/Degree C
10mV/Volt
10mV/Volt
R455
100K 1
VOLTMETER
J2-8
C413
0.1
R456
1K 1
U406A
TL074
U6
1
3
D413
1N6263
R486
100K
R458
22K
13
100K
R487
R484
10K
D418
U406B
TL074
U6
7
RF FWD
J2-10
Q403
2N5210
+5V
16
U6
13
14
15
12
1
5
2
4
(VFWD-VREFL)/4
U406D
TL074
1.00V
R491
2.49K 1
+5.00V
J3-9,10
J4-12
R464
1K
R463
100K
U8
U408
74HC4051
NUMBERS USED:
R1-91
(C2)
C1-29
R489
24.9K
D414
1N6263
C417
.001
C416
.01
C422
0.1
INH
A
B
C
R490
10.0K 1
1K
R459
100K
14
6
DPM IN
J3-19
3
R488
24.9K
12
5
X
+5.00V
SWR CAL
R468
1K
-12V
R461
10K
X0
X1
X2
X3
X4
X5
X6
X7
8
R466
56K
R465
56K
R460
11 C415
.001
C414
.01
6
11
10
9
(VFWD+VREFL)/40
1K POTH
2
RF REV
J2-11
R467
+12V
4
R457
10K
13
14
15
12
1
5
2
4
1999 WATTS
19.99
19.99V
199.9V
19.99A
199.9 Deg. C
199.9V
199.9V
J3-2
J3-4
J3-6
+5.00V
6
11
10
9
SEL A
SEL B
SEL C
X0
X1
X2
X3
X4
X5
X6
X7
X
3
C423
0.1
DPM REF
J3-17
U9
U409
74HC4051
INH
A
B
C
8
D417
+5V
R462
22K
C420
.01
U407A
TL074
RFV
J2-9
R469
10K
+12V
4
2
1
3
11
C418
.01
D415
1N6263
R472
10K POT H
R471
100K
C419
.001
R473
10K
6
5
-12V
U7
LM394
1
8C
2 C1
7B
3 B2
6E
E3
4
4
Q4065
8
7
6
5
R481
39K
R483
1M
R476
49.9K
9
10
VDD
+12V
-12V
8
9
(2.5VDC at 100W)
(.135V)
R479
1.1K 1
R482
1K
R477
7.5K
R474
3.3K
R475
49.9K
R478
10.0K 1
13
12
-6.9V
C424
1.0UF
U7
14
R480
100
10
VR401
78L05
+12V
1
C425
1.0UF
U7
U407C
TL074
7
U407B
TL074
R470
22K
8
7
6
5
D416
POWER CAL
U7
R485
100K
LM394
1
8C
C1
2
7B
B2
3
6E
E3
4
4
5
Q405
IN
OUT
C
2
U6
(Clamp SWR reading below 5W.)
DZ402
LM329DZ
+5V
U8,9 pin 7
C426
1.0UF
C429
1.0UF
R417
3.3K
VSS
8
U406C
TL074
VCC
3
-12V
C427
1.0UF
C428
1.0UF
VEE
-12V
-6.9V
FM500
METERING
103204A
J4-5
REM RFWATTS
(1.00V at 100W)
U407D
TL074
Schematic 6–4 Metering
6-11
6 - 12
FM30/FM100/FM250 User's Manual
DWG. NO.
1
2
3
4
REV.
1
201207-SCH
5
6
7
8
9
5
E . C . N.
HD7 FAN
FAN+12V
ALC / METERING
HEADER 2 .156
H
RF EXCITER
U2
2
3
J2
J1
HD42
1
2
3
4
5
6
7
8
9
10
11
12
HEADER 12
+5.00V
1K
HD31
HEADER 5 x 2
+12V
DATE
DWN
02-05-05
DW
PE
DW
Vin
NC
GND
7
2
6
3
TRM
TL072
1
U3A
-12V
+5.00V
Z9
R43
OPEN
100
C51
5
H
C52
.01
C50
1.0
+12V
8
C54
1.0
1.0
26 HEADER
J5
MCX
J6
MCX
TL072
7
U3B
6
NC
ALC
-12V
R29 1K
/LOCK
FSK IN
NC
+12V
TEMP
FAN
V-METER
RFV
RF FWD
RF REV
INPUT
/LOCK FAULT
DC SUPPLY
PAI
PAV
/LOCK
ALC
METER PAV
METER PAI
METER RFW
METER PATEMP
METER BATT
FAULT SUM
.01
1
2
3
4
5
6
7
8
9
10
NC
5
C10
HD4
HD41
HEADER 12
FOR PROTOTYPE
REF02
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
HD44
R26
J1
NC
TEMP Vout
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
J4
1
2
3
4
5
6
7
8
9
10
R25
Q1
OPEN
IRF541
1
2
3
4
5
6
7
8
9
10
.01
1
2
3
4
5
6
7
8
9
10
11
12
C27
.01
1
2
3
4
5
6
7
8
9
10
11
12
C26
1
2
3
4
5
6
7
8
9
10
11
12
1.0
TP1
VOLTMETER
G
1
C54
.01
REV
APPROVALS
CHK
CM
+12V
1
2
3
4
5
6
C25
REVISION HISTORY
DESCRIPTION
R42
4.7K
HD2
HEADER 6X1 .156
12
11
6
1
AUDIO PROCESSOR SHUNT
+12V
1
2
10
Z31
OPEN
R28 1K
G
-12V
ADD FOR M2HD-S
MOTHERBOARD ONLY
R27 1K
AUDIO PROCESSOR
RFX OUT
/LOCK
ALC
HEADER 5 x 2
HD12
COMP OUT
+12V
NC
HD5
C41
.001
1
2
3
FSK IN
NC
RIGHT
C42
.001
HEADER 3X1
NC
F
FAULT SUM
METER BATT
METER PATEMP
METER RFW
METER PAI
ALC
METER PAV
INPUT
R IN1
TEMP
R IN2
HD3
LPIN L
NC
NC
LPOUT L
LPIN R
LPOUT R
NC
Z30
JUMPER
NC
NC
C17
.01
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
NC
+12V
HD61
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
J3
J1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
F
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
+12V
-12V
/+6DB
/+12DB
L VU
R VU
+5.00V
PROC A
PROC B
PROC C
BR GR
HEADER 10 x 2
HI GR
NC
Z32
Z33
OPEN
OPEN
HEADER 13 x 2
HEADER 10 x 2
E
-12V
INSTALLED WHEN USING
AUDIO PROC. SHUNT CKT.
C18
JUMPER .01
COMP METER
COMP METER
Z28
NC
ALC
JUMPER
C19
.01
STEREO/MON
+12V
Z27
C40
OPEN
C39
OPEN
C38
OPEN
C36
.01
C35
.01
C34
.01
C33
.01
C32
.01
C30
.01
C31
.01
C29
.001
C28
.001
JUMPER
C20
.01
TP2
+12V
Z26
JUMPER
C21
.01
STEREO GENERATOR
Z25
Z24
JUMPER
C23
.01
Z23
JUMPER
+5.00V
HD22
MON L
MON R
C24
.01
NC
LPIN L
LPOUT L
LPIN R
LPOUT R
38KHZ
38KHZ
COMP METER
COMP METER
/EXT ENABLE
/EXT ENABLE
1
2
3
4
5
6
7
8
9
10
11
12
+12V
1
2
3
4
5
6
7
8
9
10
11
12
+12V
HD23
STEREO/MON
RIGHT
LEFT
Z22
OPEN
J3
1
2
3
4
5
6
7
8
9
10
11
12
_/CARRIER OFF
4
_FSK IN
R16 220
11
_ALC
R15 100
3
_COMPOSITE OUT
R14 390
10
_38 KHZ OUT
R13 390
_/EXT ENABLE
R12 1K
R IN2
1K
L IN2
1K
C5
220pF
C4
220pF
C6
220pF
FSK IN
C2
220pF
Z5
JMP2 OPEN
R11 220
/EXT ENABLE
C11
.01
C12
OPEN
C13
.001
C14
.001
C15
C16
.01
.01
OPEN
Z3
C3
220pF
Z2
JUMPER
Z1
JUMPER
JMP1 OPEN
DB15
R4
1K
COMP METER
C7
220pF
R1A
R3A
300
300
R4A
300
300
1. ALL RESISTORS ARE IN OHMS, 1/4W, 5% TOL.
2. ALL CAPACITORS ARE IN MICROFARADS.
Z13
R9
1K
Z7
R8
1K
R5
1K
R6
1K
1
Reference Drawings
2
3
50 KOHM
600 OHM
Z1, Z2 ON
Z3, Z5, Z7, Z8 OFF
Z4, Z6 OFF
Z1, Z2 ON
Z3, Z5, Z7, Z8 ON
Z4, Z6 OFF
4
OMNIA BOARD AES/EBU INPUT
3
1
Z1, Z2 OFF
Z3, Z5, Z7, Z8 OFF
Z4, Z6 ON
OPEN
Z11
EXT RTN
240
OPEN
EXT IN
1
2
3
4
5
HD6
OPEN
OPEN
R33
R34 24.9K 1%
24.9K
1%
2
R35
C48
1.0
TL072
1
U1A
HI
LO
GND
REF. FOR
XLR CON.
3
24.9K
1%
-12V
UNCONTROLLED
UNLESS OTHERWISE MARKED IN RED INK BY CM AS A
CONTROLLED COPY, COPIES OF THESE DOCUMENTS
INCLUDING ASSOCIATED ELECTRONIC REPRODUCTIONS
ARE FOR REFERENCE ONLY.
6
7
8
D3
R32
1K
C49
1.0
R38
4.02K
1%
+12V
R36
24.9K
1%
ANALOG LEFT/RIGHT
LEFT IN 1
LEFT IN 2
5
R41 1K
SCA IN
R10
B
100
OPEN
Z8
1
2
3
3
2
1
2
NON-OMNIA BOARD INPUT IMPEDENCE
A
R39
Z14
OPEN
J2
OPEN
INPUT CONFIGURATION CHART
R40
100
OPEN
R7
1K
Z10
J1
XLR
STEREO GENERATOR SHUNT
OPEN
Z12
C1
220pF
R2A
OPEN
UNLESS OTHERWISE SPECIFIED:
C8
220pF
OPEN
R2
2
1
L IN2
1K
Z4
NOTES:
HEADER 12
C9
220pF
R3
R IN1
C
J1
1N4148
12
TP5
GND
-12V
1
2
3
4
5
6
7
8
9
10
11
12
D2
_/AUTO CAR. OFF
1
2
3
4
5
6
7
8
9
10
COMP METER
5
OPEN
R1
COMP OUT
_FAULT SUM
SCA IN
13
Z6
EXT RTN
_METER BATT
EXT IN
_METER PA TEMP
6
MON_R
MON_L
EXT_IN
EXT_RTN
SCA
_METER RFW
14
R IN1
L IN1
_METER PAI
7
1
2
3
4
5
6
7
8
9
10
HEADER 5 x 2
R17 220
OPEN
Z21
R19 220
R18 220
OPEN
Z20
R20 220
OPEN
OPEN
OPEN
Z19
R21 220
Z18
Z17
R23 220
R22 220
OPEN
OPEN
Z16
Z15
R24 220
ALC
_METER PAV
15
TP4
+12V
J2
HD21
J4
8
D
+5.00V
HEADER 12
C
9
TP3
-12V
C22
.01
COMP OUT
JUMPER
D1
1N4148
B
+5.00V
HD13
Z29
HEADER 10 x 2
D
J2
HD11
L IN1
L IN2
E
1
2
3
4
5
6
7
8
9
10
HEADER 5 x 2
C43
.001
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
1
2
3
4
5
6
7
8
9
10
1N4148
V+
TEMP
GND
LEFT
R37
6
3.9K
5
APPROVALS
THESE DRAWINGS AND SPECIFICATIONS ARE THE
PROPERTY OF INTERNATIONAL RADIO AND ELECTRONICS CORP.
AND SHALL NOT BE REPRODUCED, COPIED OR USED AS
THE BASIS FOR THE MANUFACTURE OR SALE OF APPARATUS OR
DEVICES WITHOUT PERMISSION.
9
IREC
TL072
7
U1B
10
DWN
CHK
DW
11-23-04
CM
DW
11-23-04
PE
DISTRIBUTION
K
FILENAME:
INTERNATIONAL RADIO AND ELECTRONICS CORP.
25166 LEER DRIVE ELKHART, IN. 46514
WWW.IREC1.COM
Error
: logo3A.jpg file not found.
574-262-8900
TITLE:
SIZE
A
SCH, FM/IBOC MOTHER BOARD
DWG . NO .
D
SCALE :
NONE
11
REV
201207-SCH
1
PROJ NO.
SHEET
1 OF 1
12
6 - 13
R27
Rev A
D 8167-5
Illustration 6-10 Display Board
6-14
FM250G User’s Manual
Rev A
U602
LM3915
JP601
+12V
R601
68K
L VU
R602
100K
8
R604
1.2K
D601
1N4148
8
2
3
4
U601A
TL072
7
6
5.00V
R603
1K
1
C601
1.0UF
9
+12V
5
C602
1.0UF
D602
1N4148
4
3
+12V
2
-12V
1
MODE
RADJ
DL601-610
+5V
L8
DHI
L7
IN
L6
DLO
L5
V-
L3
L1
L2
YEL
12
G
G
1
8
GRN
17
GRN
18
L
1
C603
1.0UF
R VU
R607
68K
D603
1N4148
6
7
7
6
5.00V
R609
1K
5
U601B
TL072
9
8
R610
1.2K
5
C604
1.0UF
D604
1N4148
4
3
+12V
2
1
MODE
L
6
1
3
1
2
L
7
1
1
L
8
L
9
D
L
O
V
+
2
4
3
R
O
U
T
D
H
I
I
N
5
6
R
A
D
J
7
COMPOSITE
HI GR
+12V
+12V
ROUT
L8
DHI
L7
IN
L6
V-
L3
L1
L2
Y
Y
G
G
G
G
Y
1
8
R615
33K
50mA
L
2
GRN
15
L
3
GRN
18
1
5
L
4
L
5
U605
GRN
17
1
6
1
4
L
6
1
3
1
2
L
7
L
8
L
9
R624
1M
C612
.001
L
1
R616
33K
+5V
V
1
D
L
O
V
+
2
3
D
H
I
I
N
4
5
6
7
M
O
D
E
C608
.001
L4
V-
L3
L1
L2
C634
1.0UF
R633
33K
ST/MON
R657
1K BECKMAN
RF LEVEL
SW601
6
SW602
10V P-P DITHER
12
PA TEMP
DECIMAL POINT
13
R619
510
R620
220K
PATEMP LAMP
U606B
TL072
C609
1.0UF
DL659
RED
+5V
DP100
R656
220
2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3 4
1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0
DL636-643
Pin 1, upper left from front of unit.
F.S.
+12V
RF POWER
1999
SWR
19.99
ALC
19.99
PA DC VOLTS
199.9
C631
1.0UF
OUT
C
2
VDD
VCC
+5V
3
C624
1.0UF
C629
1.0UF
GRN
GRN
16
14
U10
U11
U9
GRN
7
PA DC AMPS
19.99
PA TEMPERATURE
199.9
8
-12V
+5V
-12V
2 1 1 1 1 1 1 1 1 1 1
0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1
U612
C622
1.0UF
GRN
R638
100K
C618
0.1
C617
0.1
DPM REF
R637
470K
R636
100K
199.9
VOLTMETER
199.9
GRN
UP
SW605
R651
2.2K
R628
1K
1
U609C
74HC14
5
C619
100PF
6
U609D
74HC14
9
C632
.001
R639
100K
+5V
DZ601
6.2V
DOWN
SW606
R654
1K
R640
100K
2
X0
X1
X2
X3
X4
X5
X6
X7
X
R641
10K
15
1
10
9
C621
.01
3
4
5
4
11
14
R642
10K
A
B
C
D
QA
QB
QC
QD
UP
DN
LOAD
CLR
CO
BO
R630
150
11
INH
A
B
C
COMPOSITE
MON/ST
2
4
6
8
10
12
14
16
18
20
1
3
5
7
9
11
13
15
17
19
5.00V
DPM REF
DPM IN
HEADER 10X2
3
2
6
7
SEL A
SEL B
SEL C
12
13
SCM, FM DISPLAY
1. ALL RESISTORS ARE IN OHMS, 1/4W, 5% UNLESS OTHERWISE SPECIFIED.
U609E
74HC14
10
+12V
-12V
J602
SEL A
SEL B
SEL C
RF LEVEL
5.00V
PATEMP LAMP
PADC LAMP
INPUT
LOCK LAMP
SWR LAMP
NOTES :
C614
0.1
+12V
-12V
/+12DB
/+6DB
5.00V
3
+5V
8
1
3
5
7
9
11
13
15
17
19
HEADER 10X2
U610
74HC193
U609B
74HC14
C633
.001
13
14
15
12
1
5
2
4
2
4
6
8
10
12
14
16
18
20
GND
U611
74HC4051
6
11
10
9
U609A
74HC14
C620
.01
-12V
R635
100K
SUPPLY DC VOLTS
ICL7107
C627
1.0UF
C616
0.1 POLY
GRN
VEE
VSS
C630
1.0UF
2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3 4
1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0
+12V
-12V
L VU
R VU
5.00V
PROC A
PROC B
PROC C
BR GR
HI GR
GRN
VR601
7805
DPM IN
J601
GRN
+12V
/+12DB
U609F
74HC14
DL647
RED
DITHER
D617
D616
R632
620
/+6DB
PA DC
5
U606A
TL072
IN
STEREO
+5V
INPUT
DP10
1
GRN
INPUT
DL646
RED
7
C623
1.0UF
GRN
18
GRN
DL645
RED
R650
100K
BECKMAN
PROC B
R634
5.1K
DP10
DP100
GRN
17
LOCK
UNITS
+5V
GRN
16
MONO
SWR LAMP
5.00V
R631
5.6K
-12V
TENS
V+
GRN
15
SWR
9
3
100's
L5
R629
680
5.00V
PADC LAMP
8
1
1000
DLO
GRN
14
LOCK LAMP
+12V
DL101
DISPLAY
L6
C625
0.1
DL644-647, 659
C613
.01
4
IN
GRN
13
SW603
PROC C
2 1 1 1 1 1 1 1 1 1 1
0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1
L7
DITHER
R655
4.7K
+5V
2
DHI
YEL
12
PROC A
R617
1K
Q602
MPS-A56
L8
"PILOT"
R649
10K POT H
MOD. CAL.
BR GR
330
R611
1K
ROUT
RED
11
R625
10K
R618
1.2K
+12V
L9
"110"
GRN
DL644
RED
C607
0.1
R612
1
RADJ
R652
5.6K
10
L10
R626
33K
1
0
8
2
MODE
C628
1.0UF
-12V
GRN
RED
R647
1K
L
1
0
R
A
D
J
3
+12V
4
D607
LM3914
R
O
U
T
8
1
C610
0.1
4
1K
RED
1
1
DITHER
GRN
16
1
7
2
3
DL626-635
GRN
14
Q603
2N5210
5
GRN
13
R648
D618
4
G
G
6
5
+12V
U607B
TL072
7
3
+5V
YEL
12
L4
C606
0.1
RED
R653
1K
1
-12V
11
L5
8
2
U607A
TL072
D606
1N6263
6
5.00V
U613A
TL072
8
7
R643
3.3M
R623
10.0K
5.00V
C605
.001
2.7K
1N6263
9
1.2K
R627
-12V
R622
10.0K
M
O
D
E
8
U608
LM3914
9
D605
R614
R613
1K
JP603
JUMPER
FOR BAR
R646
10M
1
0
L
1
0
LM3914
330
10
L10
L9
V+
1
4
L
5
DL11-20
RADJ
DLO
V
1
1
5
L
4
U604
Q601
MPS-A56
+12V
1
6
L
3
+5V
GRN
RED
1
7
L
2
+5V
+12V
7
5
R644
33K
GRN
16
C611
0.1
DL648-658
C626
1.0UF
GRN
R605
1K
R608
100K
+12V
50mA
15
6
Q604
2N5087
R645
100
Y
GRN
14
U603
LM3915
G
DL621-625
R606
JP602
G
GRN
13
L4
U613B
TL072
RED
11
L9
ROUT
V+
10
L10
2. ALL CAPACITORS ARE IN MICROFARADS UNLESS OTHERWISE SPECIFIED.
103206
C615
0.1
Schematic 6–6 Display
6-15
Reference Drawings
6 - 17
1
2
3
4
5
DWG. NO.
6
REV.
Q43229-6
AC
8
9
10
11
12
H
H
R1
4.7K
CARR SW
U3C
R2
10.0K
/CARRIER OFF
5
6
74HC14
R33
4.7K
D1
1N4148
+12V
VDD
G
G
R3
4.7K
U3A
/AUTO CARRIER
U3B
1
2
R4
10.0K
R23
1.0K
D2
1N4148
3
+6V
4
74HC14
VCC
DZ1
1N4735
6.2V
+12V
R9
1.0K
16
D3
1N6263
U1A
2
R8
51K
1
7
TL074
4
12
R15
2.2K
R14
220.0
+12V
C27
0.1
COMP2
R16
10.0K
RST
5
TL074
AUDIO or COMPOSITE
D6
1N4148
U1B
6
3
R6
5.1K
D4
1N6263
E
R11
100K
14
12
1%
TL074
C4
.001
R22
100K
TIME-OUT SELECT
JP1
.5
2
4
8
2
4
6
8
10
9
COUT
U3D
9
8
74HC14
INPUT FAULT
HEADER 5X2
10
COUT
D8
1N4148
1
3
5
7
9
8
U1D
CIN
7
5
4
6
14
13
15
1
2
3
Q4
Q5
Q6
Q7
Q8
Q9
Q10
Q12
Q13
Q14
DL2
RED
11
13
F
U2
74HC4060
R17
10.0K
DL1
GREEN
C1
.01
R10
75K
VSS
VDD
0.1
-12V
VCC
C26
D7
1N4148
R13
100K
GND
R7
120K
C3
.001
R5
91K
11
C2
.001
F
VDD
74HC14
R12
1.0M
PROGRAM DETECT
VDD
R18
100K
C5
1.0
POLY
R19
10.0K
U1C
E
R21
24.9K
1%
C6
1.0
POLY
NOTES:
9
8
UNLESS OTHERWISE SPECIFIED:
1. ALL RESISTORS ARE IN OHMS, 1/4W, 5% TOL.
10
TL074
R20
10.0K
2. ALL CAPACITORS ARE IN MICROFARADS.
3. FOR FM30, FM100, FM250 and FM500 UNITS,
R32 VALUE = 82.5K OHM, 1/4W, 1% TOLERANCE
FOR HARRIS UNITS, R32 VALUE = 100K OHM, 1/4W, 1% TOLERANCE
R24
100.0
+UNREG
D
U4
LM3578
12
11
R26 74HC14
100K
R49
1.5K
74HC14
FM 30/100/250 = D 6977-9
-12V
C13
100Pf
4
IN
OUT
ERR
CS
ESS
VS
7
Q1
IRF540
5
C15
0.1
2.2K
R36
2.0K
R38
1.0
0.5W
R38A
1.0
0.5W
L1
380UH
-12V
R42
1.0K
B
-12V
C22
3300/16V
C21
220/63V
U6
D13
1N5822
L3
960UH
2
L2
960UH
3
2
1
1
3
5
7
9
11
13
15
17
19
4
R41
1.0K
OPEN
C24
10/35V
D14
1N5822
C20
1800/35V
DZ4
ICTE-12
+12V
OUT
Vin
ON/OFF
4
R45
FEEDBACK
GND
10.K
1%
R44
1.1K
1%
1
5
3
LM2576-ADJ
MANUFACTURED FOR HARRIS CORPORATION
TITLE: SCH, FM/30/100/250 VOLTAGE REGULATOR
UNLESS OTHERWISE MARKED IN RED INK BY CM AS A
CONTROLLED COPY, COPIES OF THESE DOCUMENTS
INCLUDING ASSOCIATED ELECTRONIC REPRODUCTIONS
ARE FOR REFERENCE ONLY.
3
+
JP2
FM 30/100/250 = C 7746-8
2
C25
220/63V
C
C19
1000/35V
FM 30/100/250 = C 8667-5
1
+
R43
220.0
C28
1
1
UNCONTROLLED
6 - 18
C18
220/63V
DRVR V+
Q3
MPSA56
R40
10.0
Q2
MPSA06
+12V
A
C_L_SHT2_A.DOT REV. A
+
R37
6
OPEN
OPEN
L4
960 uH
HD3
FAN
COMP2
38KHZ
/CARRIER OFF
/AUTO CARRIER
Q4
MJE15028
R35
51.0
C16
2
Vin
2
4
6
8
10
12
14
16
18
20
HD2
HEADER 10X2
D15
1N4004
(TO POWER REG. BOARD)
R51
(JUMPER)
3
C14
.1
8
+
/LOCK FAULT
2
VB
2
HEADER 6
+12V
HD1
Vout
VR1
6
5
4
3
2
1
C23
330/100V
D11
MUR120
HD4
SYNC
-12V
DRVR V+
PAV
PAI
ALC
INPUT FAULT
6
5
4
3
2
1
B
3
+UNREG
R50
100
CARR SW
DRVR V+
5
VCC
R32
SEE NOTE 3
R27
620.0
METER UNREG
+12V
1
R28
68K
R29
4.12K
1%
10
6
R30
2.2K
GND
D9
OPEN
R48
10.0K U3E
E
1
13
C8
220pF
GND
7
+
R25
100K U3F
C10
56Pf
NPO
4
C
+
C7
.001
C
VDD
C11
.01
CS
OSC
+
VDD
C9
2200Pf
POLY
+IN
+
DZ2
1N966B
U5
IR2125
C12
1.0
1.5KE36A
3
V+
R39 510
2
D10
1N4148
8
-IN
D
DZ3
1
P1
R34
10.0K
Q5
MPSA06
5
6
7
8
THESE DRAWINGS AND SPECIFICATIONS ARE THE
PROPERTY OF INTERNATIONAL RADIO CORP.
AND SHALL NOT BE REPRODUCED, COPIED OR USED AS
THE BASIS FOR THE MANUFACTURE OR SALE OF APPARATUS OR
DEVICES WITHOUT PERMISSION.
SIZE
9
10
Q43229-6
C
SCALE :
NONE
A
REV
DWG . NO .
PROJ NO.
11
001,002,003
AC
SHEET
11 OF 11
12
FM30/FM100/FM250 User's Manual
Reference Drawings
6 - 19
1
2
3
4
5
6
REVISION HISTORY
DESCRIPTION
ON CHASSIS
E . C . N.
BATTERY
~
-
DC INPUT
+
C1001
0.015F
110V
~
D804
BYV72EW-150
P802
FASTON TAB
PRODUCTION RELEASE
8
DATE
DWN
10-31-03
DW
APPROVALS
CHK
CM
PE
DW
DP
274
B
CORRECTED Z3 AND Z6 UNIT STATUS FOR M2 AND FM100
01-29-04
DW
DW
DP
323
C
SWAPPED Z1, Z2 TO MATCH PWB
08-10-04
DW
DW
DP
2
F
REV
A
3
1
P801
FASTON TAB
7
P806
FASTON TAB
F
P803
FASTON TAB
CIRCUIT BREAKER
L801
P804 + UNREG IN
FASTON TAB
P805
FASTON TAB
P807
FASTON TAB
HD1
1
2
+IN
CS
OSC
C
GND
E
8
U2
7
6
1
5
2
LM3578AN
R806A
330K
2
* Z7
1
2
R807
2.2K
C805
100PF
4
VB
IN
OUT
ERR
CS
ESS
VS
C809
.1
8
R809
51.0
7
R811
6
C808
5
.0027
IR2125
R810
2.0K
D803
BYV72EW-150
1N966B 16V
3
* Z8
B
REF DES
L802
R811
R827
R828
DZ806
DZ807
R805B
200K
D805
1N4148
6 - 20
1
R818B
2.0K
2W
C813
.01UF
R817B 1
2K
2W
* Z5
TP2
R815
100.0
R816
1.0K 1%
R813
1.0K
UNIT CONFIGURATION
FM250
FM500
EURO
OPEN
SHORT
SHORT
SHORT
OPEN
SHORT
SHORT
OPEN
OPEN
H43608-1
3.3K
OPEN
OPEN
OPEN
OPEN
OPEN
SHORT
SHORT
SHORT
OPEN
SHORT
SHORT
OPEN
OPEN
H43395-5
3.3K
OPEN
OPEN
OPEN
OPEN
OPEN
SHORT
SHORT
OPEN
SHORT
OPEN
SHORT
OPEN
SHORT
H43533-1
3.3K
OPEN
OPEN
OPEN
OPEN
OPEN
SHORT
SHORT
OPEN
SHORT
OPEN
SHORT
OPEN
SHORT
H43533-1
3.3K
OPEN
OPEN
OPEN
OPEN
SHORT
OPEN
SHORT
OPEN
SHORT
OPEN
OPEN
SHORT
SHORT
H43533-1
3.3K
OPEN
OPEN
OPEN
OPEN
OPEN
SHORT
SHORT
OPEN
SHORT
OPEN
SHORT
OPEN
SHORT
H43533-1
5.11K 1%
OPEN
OPEN
OPEN
OPEN
UNCONTROLLED
UNLESS OTHERWISE MARKED IN RED INK BY CM AS A
CONTROLLED COPY, COPIES OF THESE DOCUMENTS
INCLUDING ASSOCIATED ELECTRONIC REPRODUCTIONS
ARE FOR REFERENCE ONLY.
2
* Z4
2
2
P808
PA-DC OUT
FASTON TAB
R818A
2.0K
2W
C820
0.01UF DISK
TP1
C819
.01UF
U803
OP-27GNB
2
3
DZ802
1N966B 16V
NOTES:
HARRIS M1
OPEN
SHORT
OPEN
OPEN
SHORT
OPEN
SHORT
OPEN
SHORT
H43533-1
3.3K
INSTALLED
INSTALLED
INSTALLED
INSTALLED
HARRIS M2
UNLESS OTHERWISE
SPECIFIED:
SHORT
OPEN
C818
.1UF
R822
22.0K
Q802
MPSA56
R814
22.0K
1. ALL RESISTORS ARE IN OHMS,
1/4W, 5% TOL.
OPEN
SHORT
OPEN
OPEN
SHORT
SHORT
H43533-1
3.3K
INSTALLED
INSTALLED
INSTALLED
INSTALLED
INTERNATIONAL RADIO AND ELECTRONICS CORP.
25166 LEER DRIVE ELKHART, IN. 46514
574-262-8900
Error
: logo3A.jpg file not found.
WWW.IREC1.COM
APPROVALS
5
DWN
CHK
CM
PE
DW
09-30-03
DW
09-30-03
DP
09-30-03
DISTRIBUTION
FILENAME:
TITLE:
SIZE
SCH, FM POWER REGULATOR
REV.
DWG . NO .
200915-SCH
B
200915-SCH
6
B
IREC
2. ALL CAPACITORS ARE IN
MICROFARADS.
THESE DRAWINGS AND SPECIFICATIONS ARE THE PROPERTY OF
INTERNATIONAL RADIO AND ELECTRONICS CORP.
AND ARE NOT TO BE REPRODUCED, COPIED OR USED AS THE BASIS
FOR THE MANUFACTURE OR SALE OF APPARATUS OR
DEVICES WITHOUT PERMISSION.
4
C
Q803
2N5087
6
3
FM100
C10582-2 PWB_100969-1
B_L_SHT1_A.DOT REV. A
+
OPEN
FM30
PWB_REV.G
C811
C810
330/100V
+
*
R819
.04 OHM 15W 3%
4.7UF/63V
R820
100K
FM1
A
DZ803
1N4735 6.2V
L803
30UH
7
2
*
Z1
Z2
Z3
Z8
Z7
Z6
Z4
Z5
Z9
R812B
0.1
5W
C806
R804
10.0K 1%
JUMPER
R812A
0.1
5W
L802
* DZ807
R806B
R805A
330K
2
* Z9
*
R817A
100
1
+
1
C
Q804
MPSA06
200K
* Z6
1
R821
10.0K
Q801
IRF540
8
1
C814
1/50V
VCC
C 7527-2_6 HDR
* R828
30K
4
1
56PF
V+
3
82K
2
4
3
D
C804
.01
C803
R803
C801
220PF C802
2200PF POLY
1
3
-IN
1.0K
D802
1N4148
C812
1/50V
REV.
DZ801
U801
200915-SCH
1.0K
330/100V
*DZ806
* Z1
1
2
3
4
5
6
R808
C
* R827
2
1
1
2
2
1N4735 6.2V
R802
10K
PA VOLTAGE SET
C817
330/100V
* Z3
1
1N966B 16V
24.9K
+
DWG. NO.
1
* Z2
R801B
+
E
R801A
27.4K 2
E
30UH
C816
330/100V
+
C815
330/100V
SCALE : NONE
7
PROJ NO. 533
A
C
SHEET
1 OF 1
8
FM30/FM100/FM250 User's Manual
R19
R20
Illustration 6-13 Power Amplifier-FM100/FM250
Reference Drawings
6 - 21
Rev A
Illustration 6-13 Power Amplifier
6-20
FM250G User’s Manual
Rev A
2
1
3
E . C . N.
REV
160-A
A
4
5
REVISION HISTORY
DESCRIPTION
PRODUCTION RELEASE
6
DATE
DWN
02-12-02
DW
APPROVALS
CHK
CM
PE
D
D
C1
.01
DWG. NO.
J2
C13
.01
Vout
LM35DZ
L1
C12
.01
3
200307-SCH
R5
10
R10
5.6
1W
REV.
A
NOTES:
T1
R11
5.6
1W
C10
.01
1
C11
.01
3
G1
1. ALL CAPACITOR VALUES ARE IN
MICROFARADS, 100V.
C8
.01
2. ALL RESISTORS ARE IN OHMS, 1/8W, 5%.
C9
.01
THESE DRAWINGS AND SPECIFICATIONS ARE THE
PROPERTY OF INTERNATIONAL RADIO AND ELECTRONICS CORP.
AND SHALL NOT BE REPRODUCED, COPIED OR USED AS THE BASIS
FOR THE MANUFACTURE OR SALE OF APPARATUS OR
DEVICES WITHOUT PERMISSION.
K
FILENAME:
A_L_SHT1_A.DOT REV. A
1
2
68pF, 350V
IREC
INTERNATIONAL RADIO AND ELECTRONICS CORP.
25166 LEER DRIVE ELKHART, IN. 46514
574-262-8900
WWW.IREC1.COM
SIZE
SCH, EURO 300W AMP
DWG . NO .
SCALE :
4
REV
200307-SCH
A
200307-SCH-A
3
4T
B
TITLE:
DISTRIBUTION
T2B
1TCT
PAD1
D1
R9
5.6
1W
DWN
CHK
CM
PE
C5
.01
C15
T2A
C
+t
BLF278
APPROVALS
UNCONTROLLED
UNLESS OTHERWISE MARKED IN RED INK BY CM AS A
CONTROLLED COPY, COPIES OF THESE DOCUMENTS
INCLUDING ASSOCIATED ELECTRONIC REPRODUCTIONS
ARE FOR REFERENCE ONLY.
R6
1.5
1W
D2
Q2
S
R8
5.6
1W
A
G2
R12
24, 3W
2
C6
1
C7
.01
C4
.01
R13
L2
UNLESS OTHERWISE SPECIFIED:
B
J4
GND
2
R7
1.5K
39K
Vs
Q1
TEMP.
1
J1
J3
DC IN
R14
NONE
PROJ NO.
5
518
A
A
SHEET
1 OF 1
6
Schematic 6–9 RF Output Amplifier
6-21
Rev A
1
2
3
4
5
6
E . C . N.
REV
160-A
A
7
REVISION HISTORY
DESCRIPTION
RELEASE TO PRODUCTION
8
DATE
DWN
02-08-02
DW
APPROVALS
CHK
CM
PE
F
F
RF AMPLIFIER #1
200307-PWB
E
REV.
A
E
0 deg.
IN
Z2
4
50
RF INPUT
BC2
IN
0 deg.
4
50
20W
D
1
200194-SCH
BC1
1
150W
2
ISOL
-90 deg.
3
2
INPUT COUPLER
ISOL
-90 deg.
DWG. NO.
Z1
3
OUTPUT COUPLER
RF OUTPUT
C
RF AMPLIFIER #2
200307-PWB
C
B
B
IREC
APPROVALS
UNCONTROLLED
UNLESS OTHERWISE MARKED IN RED INK BY CM AS A
CONTROLLED COPY, COPIES OF THESE DOCUMENTS
INCLUDING ASSOCIATED ELECTRONIC REPRODUCTIONS
ARE FOR REFERENCE ONLY.
A
B_L_SHT1_A.DOT REV. A
1
2
3
THESE DRAWINGS AND SPECIFICATIONS ARE THE PROPERTY OF
INTERNATIONAL RADIO AND ELECTRONICS CORP.
AND ARE NOT TO BE REPRODUCED, COPIED OR USED AS THE BASIS
FOR THE MANUFACTURE OR SALE OF APPARATUS OR
DEVICES WITHOUT PERMISSION.
4
5
DWN
CHK
CM
PE
DW
INTERNATIONAL RADIO AND ELECTRONICS CORP.
25166 LEER DRIVE ELKHART, IN. 46514
574-262-8900
WWW.IREC1.COM
09-27-01
TITLE:
DISTRIBUTION
FILENAME:
SIZE
B
SCH, EURO-AMP QUADRATURE COMBINER
DWG . NO .
SCALE :
200194-SCH-A
6
7
REV.
200194-SCH
NONE
PROJ NO.
518
A
A
SHEET
1 OF1
8
Schematic 6–10 Quadrature Power Combiner
6-22
FM250G User’s Manual
Rev A
2
1
3
E . C . N.
REV
160-A
A
4
5
REVISION HISTORY
DESCRIPTION
PRODUCTION RELEASE
6
DATE
DWN
02-20-02
DW
APPROVALS
CHK
CM
PE
D
D
DWG. NO.
L1
RF IN
200305-SCH
C2
OPEN
R1
620
R2
620
PART OF
PWB COPPER
C1
R3
560
C
4T
6.5-30pF
REV.
A
NOTES:
1. ALL CAPACITORS ARE IN PICOFARADS.
2. ALL RESISTORS ARE IN OHMS, 1W, 5%.
B
B
THESE DRAWINGS AND SPECIFICATIONS ARE THE
PROPERTY OF INTERNATIONAL RADIO AND ELECTRONICS CORP.
AND SHALL NOT BE REPRODUCED, COPIED OR USED AS THE BASIS
FOR THE MANUFACTURE OR SALE OF APPARATUS OR
DEVICES WITHOUT PERMISSION.
DWN
CHK
CM
PE
A_L_SHT1_A.DOT REV. A
2
DW
02-19-02
TITLE:
DISTRIBUTION
K
FILENAME:
1
INTERNATIONAL RADIO AND ELECTRONICS CORP.
25166 LEER DRIVE ELKHART, IN. 46514
574-262-8900
WWW.IREC1.COM
APPROVALS
UNCONTROLLED
UNLESS OTHERWISE MARKED IN RED INK BY CM AS A
CONTROLLED COPY, COPIES OF THESE DOCUMENTS
INCLUDING ASSOCIATED ELECTRONIC REPRODUCTIONS
ARE FOR REFERENCE ONLY.
A
IREC
SIZE
SCH, FM250 EURO POWER AMP RF INPUT
DWG . NO .
3
200305-SCH
A
200305-SCH-A
SCALE :
4
REV
NONE
PROJ NO. 518
5
A
A
SHEET
1 OF 1
6
Schematic 6–11 RF Input
6-23
Rev A
Schematic 6–12 DC Input
6-24
FM250G User’s Manual
P10421-9
Rev A
Illustration 6-14 RF Output Filter
6-25
Rev A
(455MHz)
(195MHz)
(176MHz)
(252MHz)
C1202
1.35PF
C1204
7.1PF
C1206
9.3PF
C1208
5.13PF
C1211
47PF NP0
R1202
* 75
R1203
10
RF OUT
RF IN
L1202
90.5NH
L1201
250NH
C1201
15.4PF
C1201A
10PF
L1203
94.1NH
C1203
40.9PF
C1217
3.5PF
C1205
38.9PF
C1209
14.1PF
C1207
37.7PF
C1209A
2PF
R1201
100
D1201
1N6263
Approx. 7V RMS
with 200W RF in.
R1209
1K
R1206
1K
C1213
.001
TURNS
LENGTH
14
0.7"
#17
3
0.6"
#12
0.5"
3
0.5"
#12
0.5"
3
0.7"
#12
0.4375"
3
0.6"
#12
I.D.
L1201
0.25"
L1202
0.5"
L1203
L1204
L1205
EXACT COIL LENGTHS ARE FACTORY-SET.
* IF NECESSARY, SELECT R1202 FOR
SWR READING OF 1.1 OR BETTER WITH
50-OHM LOAD. R1205 = R1202
R1202,R1203,C1211,D1202,C1216
ON UNDERSIDE OF CIRCUIT BOARD.
D1202
1N6263
C1212
47PF NP0
RF MONITOR
INDUCTORS
R1205
* 75
R1204
10
C1219
47PF SM
HD1201
1
2
3
C1218
47PF SM
L1205
77.9NH
L1204
87.5NH
GUAGE
C1214
.01
R1207
100K
C1215
.01
R
E
F
L
R1208
20K
C1216
.001
F
W
D
R1210
10K
RFV
D1203
1N6263
R1211
100K
C1220
.01
1 2 3 4 5
HD1202
HEADER 5
NOTES :
_______
_______
1. ALL RESISTORS ARE IN OHMS,
1/4W, 5% UNLESS OTHERWISE
SPECIFIED.
2. ALL CAPACITORS ARE IN
MICROFARADS UNLESS
OTHERWISE SPECIFIED.
3. C1201-1209A,1217 are circuit board pads.
RF Output & Reflectometer
103209
Schematic 6–13 RF Output Filter and Reflectometer
6-26
FM250G User’s Manual
Reference Drawings
6 - 25
1
2
3
4
5
E . C . N.
REV
264
M
279
316
361
ADDED TO PWB (200922-PWB-D IN LOCATION
SHOWN, AND DEPICTED ON COMPONENT MAP.
F
C23
6
C24
7
REVISION HISTORY
DESCRIPTION
8
APPROVALS
CHK
CM
DATE
DWN
PRODUCTION RELEASE
12-10-03
DW
DW
DP
PE
N
XU1 WAS 200479-TERM-10
01-29-04
DW
DW
MH
O
PWB CHG'D TO REV. C
06-14-04
DW
DW
DP
P
PWB CHG'D TO REV. D
03-22-05
DW
DW
DP
F
.01
.01
R5
OPEN
XU1
MHW6342T
C4
OPEN
R18
C8
OPEN
R7
OPEN
0
IN
GND
GND
N/C
VCC
N/C
GND
GND
OUT
3
2
1
.01
1
R2
2
R1
OPEN
R6
OPEN
C3
.01
R17
51
VR1
OPEN
1
Vout
GND
Vin
E
L2
OPEN
L1
33uH
3 +5V
C10
10pF
L3
C11
36pF
C12
36pF
C13
5pF
C14
27pF
C6
0.01
C22
OPEN
C21
OPEN
C9
OPEN
FOR FM30:
20VDC INPUT APPLIED HERE.
FOR FM100 AND FM250: 18V
C18
OPEN
FOR FM500: 20V
R16
OPEN
2
D
D
G
3
OPEN
R3
OPEN
C2
OPEN
T1
S
R4
OPEN
C5
22
P
C1
Q1
BLF245
1
2
3
4
5
6
7
8
9
D2
OPEN
J2
RF OUT
REV.
E
D1
OPEN
C15
680pF
L5
23.2uH
Q43310-4
J1
RF IN
L4
10.4uH
R8
*
FOR FM30: FEED POINT FROM PWR. REGULATOR PWB.
DWG. NO.
L6
OPEN
C7
0.01
+24VDC
J3
1
L7
OPEN
R11
4.7K
R12
R9
51
1/2W
C
D3
1N753A
6.2V
C20
OPEN
RT1
T
2.7K NTC
OPEN
C17
0.01
R13
OPEN
C
8
C16
0.01
OPEN
R10
10K
J4
U2A
3
1
U2B
5
1
2
OPEN
OPEN
NOTE:
4
C19
OPEN
7
6
UNLESS OTHERWISE SPECIFIED:
B
FM30
OPEN
OPEN
FM100
FM250
2. ALL CAPACITORS ARE IN MICROFARADS.
FM500
3 OHM 5W 3 OHM 5W 2.7 OHM 5W
R15
OPEN
INTERNATIONAL RADIO AND ELECTRONICS CORP.
25166 LEER DRIVE ELKHART, IN. 46514
574-262-8900
WWW.IREC1.COM
APPROVALS
J5
1
UNCONTROLLED
UNLESS OTHERWISE MARKED IN RED INK BY CM AS A
CONTROLLED COPY, COPIES OF THESE DOCUMENTS
INCLUDING ASSOCIATED ELECTRONIC REPRODUCTIONS
ARE FOR REFERENCE ONLY.
A
B_L_SHT1_A.DOT REV. A
6 - 26
1
2
3
THESE DRAWINGS AND SPECIFICATIONS ARE THE PROPERTY OF
INTERNATIONAL RADIO AND ELECTRONICS CORP.
AND ARE NOT TO BE REPRODUCED, COPIED OR USED AS THE BASIS
FOR THE MANUFACTURE OR SALE OF APPARATUS OR
DEVICES WITHOUT PERMISSION.
4
5
DWN
CHK
CM
PE
DW
08-28-03
DW
10-30-03
DP
10-30-03
DISTRIBUTION
TITLE:
SIZE
FM RF DRIVER
REV.
DWG . NO .
Q43310-4
B
FILENAME:
SCALE : NONE
6
B
IREC
1. ALL RESISTORS ARE IN OHMS, 1/4 WATT +/- 5% TOL.
R8 POWER LEVEL CONFIGURATION
R14
7
A
P
PROJ NO. 533
SHEET
1 OF 1
8
FM30/FM100/FM250 User's Manual
Rev A
1
2
3
4
5
6
E . C . N.
REV
160-A
7
REVISION HISTORY
DESCRIPTION
8
DATE
DWN
1
PROTOTYPE
03-08-02
DW
A
INITIAL RELEASE
03-11-02
DW
APPROVALS
CHK
CM
PE
F
ON
MOTHER BOARD
9
7
5
3
1
x
x
x
x
x
x
RF OUT
900162-1
E
(H43503-4)
LP FILTER
900160-1
RF OUT
(H43308-8)
A
1
2
3
1
ATTACHED TO
V-REG. BD.
D6977-9
PL1
900159-1
RF OUT
RF IN
HD703
P1
+UNREG
RF OUT
1
P807
GND
x
x
x
D
HD4
6 C0ND. RIBBONCBL
A11570-0235E
A11572-0235E
A10120-18B4
HD701
HEADER 6
REV.
A11569-01500
A10120-22B3
BOTTOM COVER FAN
6
5
4
3
2
1
A11569-01500
P805
1
P804
1
200544-SCH
A11571-01606
DRVR V+
x
x
x
RF IN
A11573-01500
1
2
3
4
5
VOLTAGE REGULATOR
HD702
6 C0ND. RIBBONCBL
DWG. NO.
(2X) A10120-22B2
900409-1
20 C0ND. RIBBONCBL
RF DRIVER/
POWER AMPLIFIER
900160-1
A10120-22B0
EURO AMP MODULE
1
2
3
4
5
6
10
8
6
4
2
PL1004
TEMP SENSE
RF IN
E
TO
MOTHER BOARD
HD502
HD505
3
2
1
3
2
1
TO
MOTHER BOARD
PL1002
PA FAN
F
20 C0ND. RIBBONCBL
TO
MOTHER BOARD
HD503
POWER REGULATOR
RF MON
1
C
NEUTRAL
INTERPOWER 83544010
A
200430-CBL
.27mH
120/240 VAC
50/60HZ
HOT
D
*
.27mH
N
HOT
GND
AC INPUT
ASTEC
MP6-3X-00
P808
PA DC OUT
200433-CBL
(H43502-6)
C
200432-CBL
V1
DC OUTPUT
S1002
CARRIER
SEE CHART
200517-CBL
*
B
VOLTAGE
FUSE SIZE
120V
10A
240V
4A
S1002
200431-CBL
IREC
200429-CBL
POWER
APPROVALS
UNCONTROLLED
UNLESS OTHERWISE MARKED IN RED INK BY CM AS A
CONTROLLED COPY, COPIES OF THESE DOCUMENTS
INCLUDING ASSOCIATED ELECTRONIC REPRODUCTIONS
ARE FOR REFERENCE ONLY.
A
B_L_SHT1_A.DOT REV. A
1
2
3
THESE DRAWINGS AND SPECIFICATIONS ARE THE PROPERTY OF
INTERNATIONAL RADIO AND ELECTRONICS CORP.
AND ARE NOT TO BE REPRODUCED, COPIED OR USED AS THE BASIS
FOR THE MANUFACTURE OR SALE OF APPARATUS OR
DEVICES WITHOUT PERMISSION.
4
5
DWN
CHK
CM
PE
DW
INTERNATIONAL RADIO AND ELECTRONICS CORP.
25166 LEER DRIVE ELKHART, IN. 46514
574-262-8900
WWW.IREC1.COM
03-08-02
TITLE:
DISTRIBUTION
FILENAME:
SIZE
B
SCH, EURO 250 CHASIS INTERCONNECT
DWG . NO .
200544-SCH
6
B
SCALE :
7
REV.
200544-SCH
NONE
PROJ NO. 518
A
A
SHEET
1 OF1
8
Schematic 6–15 Chassis Wiring
6-29
Rev A
Illustration 6-16 Receiver Board
6-30
FM250G User’s Manual
Rev A
Schematic 6–16 Receiver Board
6-31
Rev A
6-32
FM250G User’s Manual
Rev A
Section 7—Service and Support
We understand that you may need various levels of support or that
the product could require servicing at some point in time. This
section provides information for both of these scenarios.
Service and Support
7—1
7.1 Service
The product warranty (see opposite page) outlines our responsibility for defective products.
Before returning a product for repair or replacement (our choice), call our Customer Service
department using the following telephone number:
(866) 262-8917
Our Customer Service Representative will give you further instructions regarding the return
of your product. Use the original shipping carton or a new one obtained from Crown. Place
shipping spacers between the slide-out power amplifier assembly and the back panel.
Please fill out the Factory Service Instructions sheet (page 7–5) and include it with your returned product.
7.2 24–Hour Support
In most instances, what you need to know about your product can be found in this manual.
There are times when you may need more in-depth information or even emergency-type
information. We provide 24–hour technical assistance on your product via a toll telephone
call. For emergency help or detailed technical assistance, call
(866) 262-8917
You may be required to leave a message at this number but your call will be returned
promptly from our on-call technician.
7.3 Spare Parts
To obtain spare parts, call Crown Broadcast Service at the following number.
(866) 262-8917
You may also write to the following address:
International Radio & Electronics Corporation
25166 Leer Drive
Elkhart, Indiana, U.S.A. 46514-5425
7-2
FM600 User’s Manual
Rev A
Three-Year Limited Warranty
North America Only
SUMMARY OF WARRANTY
We, Crown Broadcast, a business unit of International Radio and Electronics Company, Inc., 25166 Leer Drive, Elkhart,
Indiana 46515–2000 warrant to the ORIGINAL PURCHASER of a NEW Crown Broadcast product, for a period of three (3)
years from the date of purchase by the original purchaser (the “warranty period”) that the new Crown Broadcast product is
free of defects in materials and workmanship and will meet or exceed all advertised specifications for such a product. This
warranty does not extend to any subsequent purchaser or user, and automatically terminates upon sale or other disposition of
our product.
ITEMS EXCLUDED FROM THIS CROWN BROADCAST
We are not responsible for product failure caused by misuse, accident, or neglect. This warranty does not extend to any
product on which the serial number has been defaced, altered, or removed. It does not cover damage to loads or any other
products or accessories resulting from Crown Broadcast product failure. It does not cover defects or damage caused by use of
unauthorized modifications, accessories, parts, or service.
WHAT WE WILL DO
We will remedy any defect, in material or workmanship (except as excluded), in our sole discretion, by repair, replacement, or
refund. If a refund is elected, then you must make the defective or malfunctioning component available to us free and clear of
all liens or other encumbrances. The refund will be equal to the actual purchase price, not including interest, insurance,
closing costs, and other finance charges less a reasonable depreciation on the product from the date of original purchase.
Warranty work can only be performed at our authorized service centers or at our factory. Expenses in remedying the defect
will be borne by Crown Broadcast, including two-way surface freight shipping costs within the United States. (Purchaser
must bear the expense of shipping the product between any foreign country and the port of entry in the United States and all
taxes, duties, and other custom’s fee(s) for such foreign shipments.)
HOW TO OBTAIN WARRANTY SERVICE
You must notify us of your need for warranty service not later than ninety (90) days after the expiration of the warranty
period. We will give you an authorization to return the product for service. All components must be shipped in a factory pack
or equivalent which, if needed, may be obtained from us for a nominal charge. Corrective actions will be taken within a
reasonable time of the date of receipt of the defective product by us. If the repairs made by us are not satisfactory, notify us
immediately.
DISCLAIMER OF CONSEQUENTIAL AND INCIDENTAL DAMAGES
You are not entitled to recover from us any consequential or incidental damages resulting from any defect in our product.
This includes any damage to another product or products resulting from such a defect.
WARRANTY ALTERATIONS
No person has the authority to enlarge, amend, or modify this warranty. The warranty is not extended by the length of time
for which you are deprived of the use of the product. Repairs and replacement parts are provided under the terms of this
warranty shall carry only the unexpired portion of this warranty.
DESIGN CHANGES
We reserve the right to change the design of any product from time to time without notice and with no obligation to make
corresponding changes in products previously manufactured.
LEGAL REMEDIES OF PURCHASER
There is no warranty which extends beyond the terms hereof. This written warranty is given in lieu of any oral or implied
warranties not contained herein. We disclaim all implied warranties, including without limitation any warranties of
merchantability or fitness for a particular purpose. No action to enforce this warranty shall be commenced later than ninety
(90) days after expiration of the warranty period.
Crown Broadcast, International and Radio Company, Inc.
25166 Leer Drive, P.O. Box 2000, Elkhart, Indiana 46515–2000
Phone: (574) 262-8900; FAX: (574) 262-5399
Service and Support
7—3
Factory Service Instructions
To obtain factory service, complete the bottom half of this page, include it with the unit, and ship to:
International Radio & Electronics Corporation
25166 Leer Drive
Elkhart, Indiana, U.S.A. 46514-5425
For units in warranty (within 5 years of purchase from any authorized Crown Dealer): We pay for
ground UPS shipments from anywhere in the continental U.S. and Federal Express Second Day
service from Hawaii and Alaska to the factory and back to you. Expedited service/shipment is
available for an additional charge. You may forward your receipt for shipping charges which we will
reimburse. We do not cover any charges for shipping outside the U.S. or any of the expenses
involved in clearing customs.
If you have any questions about your Crown Broadcast product, please contact Crown Broadcast
Customer Service at:
Telephone: (866) 262-8917 or (866) 262-8972
Fax: (866) 262-8909
Company:
Name:
Shipping Address:
Phone Number: Fax:
Model:
Serial Number:
Purchase Date:
Nature of the Problem
(Describe the conditions that existed when the problem occurred and what attempts were made to correct it.)
Other equipment in your system:
If warranty has expired, payment will be:
Cash/Check
VISA
Please Quote before servicing
Card Number:
Exp. Date:
Return Shipment Preference if other than UPS Ground:
Mastercard
Signature:
Expedite Shipment
Other
ENCLOSE WITH UNIT—DO NOT MAIL SEPARATELY
Service and Support
7-5