The sonar range data converter (Figure 1-12-5), mounted at the aft end of the SENSO/Sonar Operator station, provides a means of correcting for magnetic compass variation angles so that true north may be indicated. This is done by routing compass signals from the hydrophone, via a compass follower in the sonar receiver, to the sonar range data converter where variation angle corrections are inserted by means of an electro-mechanical resolver. After processing in the converter, the signals are returned to the circuitry in the sonar receiver. The system then behaves as though the compass indicated true north and true north will be displayed at the top of the azimuth and range indicator display. Bearing, measured with the indicator cursor, will then be recorded as a true bearing.

Located on the converter front panel are two multi-pin connectors, a test connector, and a dial and knob arrangement for manual adjustment of the resolver in order to correct for known magnetic compass variation angle.