This small FM spy transmitter uses three transistors with an RF amplification stage. We found it in an Australian publication from 1991.
This circuit is from the Motorola Linear Databook of 1990. The circuit controls a Triac from a...
The circuit shown uses the LM324, but can be implemented with other operational ones. The source...
This circuit makes use of a stroboscopic tube, a component that no longer exists today. The...