We found this circuit in the Linear Applications Handbook of the 1994 National Semiconductor. The transistor must be a high voltage type and the LM3900 power supply must be symmetrical.
This circuit was used to reinforce radio signals for listening on the phone, making it possible to listen...
This synthesizer circuit was found in a Radio Electronics magazine from May 1983. The circuit uses...
The circuit that gave rise to this configuration was found in a magazine of the 1980s with the...