This small phonographic amplifier was found in a 1967 General Electric documentation. The integrated circuit is from that time, providing 1.5 W of output power.
Found in Radio Electronics from the 90s, this circuit uses a 741 and can be changed to other...
With a light pulse on the Q1 sensor the circuit turns on and locks. To switch off, a light pulse...
This 10-minute timer was found in the July 1994 Radio Electronics magazine. The relay must be...