This optical theremin was found in a 90s Hands-On Electronics. The basic frequency is given by C1 and the output is made in a speaker through a small output transformer.
This circuit hás a Power output of more than 1 W. It is used in small experimental or low power...
This circuit was found in a former Popular Electronics. The timing is given by R1 and C1, R4 and...
This circuit was obtained in the publication 101 Electronics Projects of 1979. The circuit can be...