This circuit was found in an old American publication. The transformer is the type of output found in old transistor radios. The transducer is crystal headphone.
This oscillator with signal amplitude adjustment generates a 6.5 Hz signal with the values of the...
We found this circuit for guitar training in an English documentation from 1989. The components are from...
This circuit was found in a Hands On Electronics from the 90s. The circuit does not need a...