This circuit is from a documentation from the 70s. The circuit uses logic gates of the time, which in many cases were arrays of transistors allowing use as audio amplifiers, as in this case.
This circuit was found in an American documentation from 1970. We can increase the number of...
This amplifier with the RCA CA3018 integrated circuit was found in the August 1970 issue of Radio...
This three-transistor circuit can control 3 V relays or servos from 17 MHz modulated transmitters. The...