This is the 1968 MR480 commercial cassette recorder circuit. The circuit was fully transistorized and powered by 4 large batteries. We found the diagram in a Japanese documentation of the time.
We found this circuit in a 2005 documentation. The circuit uses an infrared piezo sensor...
This circuit was found in a 1995 documentation. It deactivates a power supply in the event of a...
This circuit was found in the September 1993 Electronics Now magazine. It is based on the 555 and...