This circuit was found in an English publication from 1967. The circuit is for listening on a phone. Transistors are types of germanium of the time.
This circuit will trigger a buzzer with an oscillator if the ignition key is removed with the...
This circuit is from 1999 documentation and the indicated power is PMPO for a load of 4 ohms. Two...
This circuit is from old documentation having a gain of approximately 35 dB at 1 kHz with 2.2 mV...