B-1
APPENDIX B: MODEL 4325E RESPONDER
The Model 4325E Responder is optionally installed in the 4200 Series Tow Vehicles. The responder consists
of a transducer that is molded into the nose of the tow vehicle and a Responder board in the tow vehicle.
It functions with the ORE Offshore Ultra Short Baseline (USBL) Broadband Acoustic Tracking System (BATS)
to provide tow vehicle positioning by transmitting an acoustic pulse in response to a trigger input. The
specifications for the Model 4325E Responder are listed in T
ABLE B-1. The responder beam pattern is
shown in F
IGURE B-1.
Source level: 173 dB/watt re 1 µPa @ 1 m
a
Beam pattern: ±20° @ 30° up angle from the nose
Depth rating: 2000 m (6560 ft)
Transmit signal: 24–28 kHz chirp
Weight in water: 0.225 kg (0.5 lb)
Mounting: Integral to the tow vehicle nose
Turn around time: 4 ms from negative trigger edge (typical)
Table B-1: Model 4325E Responder Specifications
a. The Responder board provides approximately 200 watts of power to the transducer.
Therefore Source Level = (200 watts) 23 dB + 173 dB/W = 196 dB re 1 µPa @ 1 m.