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 Electronic Design from the 90's, this circuit uses common components. The circuit is...
When the sensor receives light, the relay closes its contacts and remains so even after the light...
This circuit produces pulses of 90 V at intervals that can reach 5 minutes. The circuit is from a...