Found in American documentation from the 90's, this circuit is very current and can be implemented with transistors of general use. Never use a power supply without a transformer.
This circuit uses a diode as a radiation sensor. The operational ones are old because the...
This circuit generates a signal in the tone-modulated FM range for tuning receivers. The circuit is...
The circuit shown was found in a 1967 RCA manual. Modern equivalent components can be used. The...