Found in old documentation, this circuit can generate pulses from 400 to 4000 Hz with active cycle control from 1% to 99%.
This circuit of a 1978 American publication monitors a telephone line by triggering a relay. The...
This interesting FET-tester circuit was obtained from an old American documentation. The bipolar...
This old VHF TV booster that also serves FM was found in Radio Electronics magazine from April...