ES303547A1 - Echo sounder - Google Patents

Abstract

In a pulse echo-sounder for depth-recording or fish location, the echo period is measured by gating a clock-pulse counter on with the transmitted pulse and off with the echo pulse, the counter feeding a digital display with a stored read-out in terms of distance. In the embodiment of Fig. 2, ultrasonic transmitter (2) drives a magnetostrictive transmitting-receiving transducer (4) and echo pulses are amplified by an amplifier (3) (these may form part of a known system). In a unit (5), pulses from transmitter (2) and amplifier (3) are shaped and used to open a gate (7) to feed clock pulses from a generator (6) to a binary counter (8) during the echo period. A bank of relays (9) converts the binary count to a three-figure decimal reading which is displayed on digital indicator lamps in a unit (10) and in slave read-out units (11), and which is printed out on paper tape by a printer (12). The frequency of the clock pulses from generator (6) may have one of four predetermined values in the range 390 c/s. to 7500 c/s. to give a depth reading in decimetres, metres, feet or fathoms, the particular unit of measurement being displayed. In order to prevent flicker of the read-out the relays in the bank (9) are provided with hold-in contacts and store the read-out information until deenergized simultaneously by a control circuit (13). A timing unit (15) determines the rate at which echo sounding measurements in display (10) are changed and a recording device (16) may be used to provide a conventional echo gram.