This 4-transistor timer was found in the April 1975 issue of Radio Electronics magazine. It uses both single-ended and single-junction transistors to provide a dual audio output.
This circuit is from 2002 documentation. It injects a signal into a power amplifier and measures the...
The integrated circuit used in this project is not the most common. The use of a crystal...
This configuration was found in an American publication from the 90s. Operators admit equivalents just...