This circuit was found in American documentation from the 90's. The transformer determines the output voltage. The transistor must be equipped with a heat sink.
This is yet another version of the light-controlled oscillator that can be found on this website. This...
Originally created to feed the filaments of a 12AX7 as an audio preamplifier to eliminate the...
The incidence of light in the LDR causes this circuit to start operating, emitting a sound whose...