This signal injector and tracer (follower) was found in an old American documentation. The transistors can be general use and power is made with one or two common cells.
This other circuit from the June 1968 Radio Electronics magazine has a driver transistor and a...
The TDA7000 is a Philips integrated circuit that contains a complete FM receiver with the need for...
Using a 4N33 optical coupler, we have in the figure an optical interface for TRTL circuits,...