This 1950s audio amplifier uses output tubes of type 1625 in its output stage. The Class B circuit provides a few watts of power and uses transformers that are not readily available today.
This circuit provides a reference voltage for calibration. He uses a diode in a small thermal...
This circuit for model making was found in an English documentation. The SCR can be the TIC106, and...
The operational amplifier used in this circuit is no longer very common, but the configuration can be adapted...