Found in a 1969 EDN, this high current circuit, not indicated in the documentation, uses transistors from that time. The input voltage can be between 9 and 11 V.
This is a circuit found in a 1970's Radio Electronics. The circuit works with virtually any triac...
This is a amplifier for XTAL high impedance earphones or piezoelectric types. Current drain is...
This is the receiving circuit for the transmitter given in the previous circuit. The circuit is...