This is a diagram of a 1970s reel or tape recorder. It is an Italian Geloso recorder, quite popular at the time. The circuit is a reference for equipment recovery.
This simple oscillator with just one transistor has a frequency determined by the characteristics of the...
This Zero Crossing Detector was found in a 1972 RCA manual, but it can be made using any modern...
The circuit shown was found in a Japanese publication from the 1960s. Transistors can be...