We found this circuit in a spy book from the 90s. Transistors admit equivalents and the coil can be designed as in the CB19425E project. Power is provided by cells or 9 V battery.
This circuit was used to reinforce radio signals for listening on the phone, making it possible to listen...
This transistor amplifier does not use a source with a transformer being fed directly by the power...
This TTL circuit found in the September 1996 issue of Electronics Now magazine doubles the...