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.
In the figure we have the way to connect 6 solar cells in order to obtain higher voltage and...
This circuit has a maximum frequency of 10 kHz and a linearity better than 0.01%. The circuit is...
This circuit was obtained in a 1961 magazine, but it can be easily assembled today, as the...