a function of the water depth the depth signal is fed via line 42 to a suitable amplifier or line driver 44 which functions to increase the value thereof to compensate for line losses as the same is remotely fed to the instrument head 300 via line 46 although not illustrated a signal or pulse extender circuit may be provided in line 46 to adjustably compensate for the installed position of transducer 30 below the water level suitable circuit elements are located within head 300 to convert the signal on line 46 into a digital read out in terms of depth to this end an input or pulse shaping circuit 48 is provided which functions to eliminate imperfections and variations in the shape of the output signal from amplifier 44 and to convert the same into a nearly pure pulse at the output 50 and 52 thereof for delivery to gate and latch circuits 54 and 56 respectively this pulse in line 50 34 opens 34 the gate 54 to permit a pulse train to be delivered from oscillator 58 via line 60 to the accumulator portion of a counter 62 via line 64 at the completion of the signal cycle in line 52 the latch circuit 56 triggers via line 66 the transfer of the data or pulses in the accumulator portion of counter 62 to the memory portion thereof the reset circuit responds to the end of each latch cycle and functions via line 70 to reset the counter accumulator for the next cycle the data.