This circuit with current up to 100 mA according to the transformer was found in the Radio Electronics magazine of October 1991. The regulation is done directly by the zeners.
This version of the circuit is from 2000, using a source of negative voltage that allows to obtain...
This somewhat complex circuit was found in the May 1984 issue of Radio Electronics magazine. The...
This basic circuit is from an old documentation. The relay must be 50 mA maximum and must have a...