Found in General Electric's 1969 documentation, this circuit uses two Foto Darlingtons to control the SCRs driving phases. SCRs can be equivalent current types.
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...