This is an amplifier circuit intended for modulating transmitters. The 5-tube circuit is from an American manual from 1947. The power supply uses a transformer.
This sensitive microammeter was found in documentation from the 1980s. The accuracy of the circuit...
This circuit produces modulated tones in a loudspeaker. The effects can be adjusted by the...
We found this circuit in an old documentation from the 70s. The circuit can use any varicap and...