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.
Found in an old Radio Electronics, this circuit uses common components today. The resistors of the IC...
This circuit was published in an article in Electronics Now magazine in October 1995. The circuit...
This DC-DC converter was found in old RCA documentation. The circuit operates at 15 kHz. The...