C-Max CM2 - USBL Transponder Bracket; USBL Bracket Introduction; Fitting the USBL Bracket

CM2 Sidescan Sonar User Manual
21. USBL TRANSPONDER BRACKET
Introduction
Where accurate tracking of the position of the towfish is required, C-MAX recommends the use of an ultra-
short-baseline (USBL) acoustic tracking system. Suitable USBL systems are available from several
manufacturers, and should be chosen so that their effective range is at least that of the maximum length of
tow cable to be used with the CM2 system. These systems require the use of transponder on or near the
towfish.
The purpose of the CM2 USBL bracket is to hold a USBL transponder securely to the tow cable terminator. If
the transponder is simply secured to the terminator using duct tape it may generate eddy currents and
oscillate; these oscillations may be enough to fracture the bail arms eventually.
The USBL bracket also holds the transponder at an angle so that it is closer to pointing at the USBL
transceiver array fitted to the towing vessel.
Fitting the USBL Bracket to the Tow Cable Terminator
Fitting the bracket
Remove the screw holding the safety lanyard shackle to the terminator. Slide the transponder bracket over
the tow cable and then lower it around the terminator. as shown in the illustration. Replace the screw through
both the bracket and terminator and secure it with the original locknut.
Secure the transponder to the bracket using worm drive clamps or cable ties.
Version 3.6 (2008)
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