This amplifier with old germanium transistors is from a 1957 documentation. The power is a few hundred milliwatts and the transformers are common types of driver and output of the time.
We found this circuit in an American publication from the 1990s. The triac must be equipped with a heat...
This TTL circuit uses LED indicators and must be powered by a voltage of 5 V. The capacitor...
This circuit uses an integrated CMOS having the frequency determined by the resistors and...