Designed for the audio track, this circuit was found in a Popular Electronics from the 90's. Other operational can be used and R7 can be 470 k. The frequency is 1 kHz.
The PA222 integrated circuit used in this project from an American 1967 documentation is not...
This circuit with an optical path sensor was found in a 1995 documentation. The circuit fires...
This circuit was found in an 80's Electronic Design. It amplifies TTL fast signals for a coaxial...