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 a publication for radio amateurs from the 1990s, this circuit makes it possible to...
I found this circuit in a Popular Electronics from November 1999. The magazine is no longer...
This simple transistorized receiver with earphone was found in a Japanese publication from the...