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 simple source with zener regulation is ideal for experimental projects with operational...
This circuit is from a 1977 Signetics manual. BC107 transistors can be replaced with BC547 and...
In the figure we have an old circuit for controlling two low-power lamps. The circuit is from...