M155
Low-Cost Dual-Frequency
This low-cost “blister-type” transducer combines two popular
fishfinding frequencies in one housing. Its design is easier
and less costly to install than magneto-restrictive transducers
requiring steel tanks. The dual-frequency 28 kHz and 200 kHz
models offer high and low-frequencies for species specific
fishfinding. The single-frequency 38 kHz model features a
highly-effective, thirteen-element array that has excellent,
deep-water, fishfinding performance.
External-Mount
Options
•Temperature sensor
Features
•Impedance to customer specifications using matching transformer
1 - 1.2 kW
Applications
•Commercial fishing vessels
•Shallow to deep-water fishfinding
•Low-ringing, low-sidelobe, 28 kHz array allows
fishermen to see bottom structure clearly and to easily discriminate between bottom structure and target fish
•Narrow-beam, low-ringing, 200 kHz ceramic provides clear bottom detail and can detect small bait fish
•Fairing vertically orients sound beams for stronger
return echoes resulting in optimal sounder
performance
•Stuffing tubes are available to form a watertight conduit for cable routing and are available in a
variety of materials to match all hull types
•Can be mounted as an in-hull in a fiberglass hull for precise echosounding—even at speeds over 20 knots (23 MPH)
•Fairing is easy-to-cut and will not swell or rot
•Streamlined shape minimizes drag
•All mounting hardware included
•Seamless, SEALCAST™, urethane housing for long life underwater
www.airmar.com
M155
Technical Information
Frequencies
Configuration
Beamwidth
(@-3 dB)
RMS
Power
(W)
FOM
(dB)
Q
24° x 37°
1 kW
-20
9
28 kHz-G
Series
Impedance
(R-jX)
60-j0(Ω)
A
SPECIFICATIONS
Weight: Varies depending on configuration (Call for weight)
Acoustic Window: Urethane
Material Housing: Cast urethane
28 kHz-G
24° x 37°
1 kW
-17
9
150-j0(Ω)
11° x 21°
1.2 kW
-10
6
70-j0(Ω)
6°
1 kW
-15
10
100-j160(Ω)
DIMENSIONS
B
38 kHz-D
C
200 kHz-AWlq
D
Cable
ø 10 mm
(0.40”)
35mm
(1.38”)
Bushing
Technical Data—28 kHz-G
TVR
155
150
RVR
-170
-175
-180
-185
-190
24 26 28 30 32 34 36
Frequency (kHz)
Dimension
A
RVR in dB re 1 Volt/µPa
dB(3)
170
165
160
dB(2)
dB(1)
TVR in dB re 1µPa/Volt at 1 m
FOM
-10
-20
-30
ø 25mm
(1.00”)
-40
130 mm
(5.12”)
-50
24 26 28 30 32 34 36
Frequency (kHz)
24 26 28 30 32 34 36
Frequency (kHz)
Directivity Pattern—28 kHz-G
20°
40°
10°
0°
30°
10°
238 mm (9.38”)
20°
30°
-10 dB
314 mm (12.38”)
40°
50°
50°
Configuration
Dimension A
60°
C
76 mm (3.00”)
70°
A, B, & D
84 mm (3.31”)
-20 dB
60°
-30 dB
70°
-40 dB
80°
80°
90°
90°
140° 150° 160° 170° 180° 170° 160° 150° 140°
Fore-Aft Axis
Port-Starboard Axis
©Airmar Technology Corporation
M155_rF
05/29/14
As Airmar constantly improves its products, all specifications are subject to change without
notice. All Airmar products are designed to provide high levels of accuracy and reliability,
however they should only be used as aids to navigation and not as a replacement for
traditional navigation aids and techniques. SEALCAST™ is a trademark of Airmar Technology
Corporation. Other company or product names mentioned in this document may be
trademarks or registered trademarks of their respective companies, which are not affiliated with
Airmar.