This circuit was obtained in a 1967 Electronics World. The components are still common today, the SCRs can be replaced by equivalents and the unijunction transistors the 2N2646.
This circuit is powered by 1.5 V and has a long lifespan as it consumes only 320 uA. The circuit is...
) Suggested by Philips in a 1968 documentation this circuit has very high 10 ohm on-load voltage...
With this circuit, from a 1991 publication, it is possible to regulate the output of a symmetric source...