DRONEPIC
RADIO CONTROLLER
TRANS-RECEIVER SYSTEM
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Specifications：
(1) Channels: 9 Channels TH9X
(2) Uses: Helicopter ,airplane, glider
(3) RF power: less than 20db
(4) Modulation: GFSK
(5) Code type: PPM/PCM
(7) power:12VDC(1.5AA*8)
CHANNELS
• Each channel allows one individual thing on
the aircraft to be controlled.
• One channel each for throttle and turning
right and left.
• One channel each for pitching forward and
backward and rolling left and right.
• With more channels than just four, you can
even have switch to add functionality on the
quadcopter.
MODES
Modes
• There are 2 different Modes – mode one and
mode two.
• The mode one configuration has the elevator
control on the left joystick and the throttle on
the right one.
• The mode two configuration has the elevator
control on the right joystick and the motor
throttle on the left one
FREQUENCY
• Frequency
• There are two main frequencies we use for radio
transmitter, 72Mhz and 2.4Ghz.
• 2.4 GHZ is a newer one, and it’s currently the
most common frequency. You get a shorter
antenna, but usually shorter range than the
72Mhz. Another good thing is you can usually get
away flying with other people, who are using
2.4Ghz as well, but different brands transmitter
module.
WORKING OF TRANSMITTERS
• A radio transmitter is an electronic
circuit which transforms electric power from
a electrical mains into a rapid RF alternating
current.
• The rapidly reversing current can radiate off a
conductor (the antenna) as electromagnetic
waves (radio waves).
• The transmitter also impresses information
signal onto the carrier frequency signal.
MESSAGE SIGNAL ENCODING
TECHNIQUES
PCM
• PCM(Pulse Code Modulation) is a method of
converting an analog into digital signals.
Level
0
1
2
3
4
5
6
7
Code word
000
001
010
011
100
101
110
111
PPM
• Our area of interest is PPM.
• PPM(Pulse-position modulation) is a form of
signal modulation in which M message bits
are encoded by transmitting a single pulse in
one of possible required time-shifts. This is
repeated every T seconds, such that the
transmitted bit rate is bits per second.
CIRCUIT DIAGRAM OF PPM
MODULATION TECHNIQUE
• A GFSK modulator is similar to a FSK modulator,
except that before the baseband waveform
(levels −1 and +1) goes into the FSK modulator, it
is passed through a Gaussian filter.
• Gaussian filtering is a standard way for reducing
spectral width and make the transition smoother
also called "pulse shaping".
• In ordinary non-filtered FSK, at a jump from −1 to
+1 or +1 to −1, the modulated waveform changes
rapidly, which introduces large out-of-band
spectrum.
WORKING OF RECEIVERS
• When they strike the antenna of a radio
receiver, the waves excite similar (but less
powerful) radio frequency currents in it. The
radio receiver extracts the information from
the received waves. A practical radio
transmitter usually consists of these parts:
CIRCUIT DIAGRAM OF FSK RECEIVER
RC Transmitter and Receiver Binding
• Proper binding should be done prior to
communicating the Trans-Receiver pair
and the pair should be of the same
brand.