This simple circuit was found in an English magazine that no longer exists, January 1970 issue. This is a well-known audio oscillator configuration that is activated by the low resistance between the probes. The transistors can be the BC548.
This simple circuit was found in an English magazine that no longer exists, January 1970 issue. This is a well-known audio oscillator configuration that is activated by the low resistance between the probes. The transistors can be the BC548.