This simple source with zener regulation is ideal for experimental projects with operational amplifiers. Other voltages can be obtained by changing the zeners and the transformer.
In fact, we can say that this circuit found in documentation from the 90s, consists of an intercom...
The basic integrated circuits of this 1988 multimeter are no longer very common today, but if...
This circuit is from an old publication of the 70's. It can be implemented with modern transistors like the...