We found this receiver circuit for modulated light in a 90s Popular Electronics. Equivalent audio amplifiers can be used. Transistors are commonly used.
The circuit shown is from the National Semiconductor Linear Applications Handbook of 1994. using...
This circuit was obtained in the publication 101 Electronics Projects of 1979. The circuit can be...
Found in a 90s Popular Electronics, this circuit uses a 741 to generate frequencies from 0.1 to 30...