We found this circuit in a Hands-On Electronics from the 90s. The circuit must be connected to an external amplifier. Frequency control is capacitive, using an antenna for this purpose
We found this circuit in the December 1998 issue of Electronics Now magazine. RF transistors such...
This circuit was found in an American documentation from the 80's. The sensor is a special...
This circuit automatically controls the degree of illumination. As the circuit is from 2001, it...