This simple circuit is intended to test the zener test. RV1 can be calibrated in terms of voltage. The maximum voltage of the tested zener is that used in the circuit supply.
Found in Philips documentation from the 1970s, this circuit uses components from the era. The...
Two transistors on a regenerative switch are used to trigger a triac. This circuit is from the RCA...
The opening of the sensor in this circuit of the 70's causes an integrated buzzer of the Sonalert type...