Ultrasonic receiver circuit diagram for echo detection distance

The operating voltage of this circuit is 9V, the current consumption is only 5mA, the frequency can be adjusted within the range of 150 to 180kHz, and the bandwidth is about 20kHz to ensure that only pulses wider than 70us can pass through and be amplified.

The receiver input terminals are directly connected to the sensor and thus to the oscillator. When an ultrasonic pulse occurs , the signal voltage at the base of T1 is limited to a lower value by diodes D1 and D2. Transistors T1 and T5 form a two-stage high-frequency amplification, which is then rectified by D3 to control the output transistor T6 as a threshold switch, whose threshold is adjusted by R6. Transistors T2, T3, and T4 are additional stages used to control the first high-frequency stage.

Transformer winding data: terminals 6 to 1: 200 turns, 0.03mm copper enameled wire; terminals 3 to 2: 95 turns, 0.03mm copper enameled wire.