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.
The time the output is high (1) of a TLCSSB in the astable configuration depends on Ra and C. The...
Found in a publication from the 60's, this power supply has no regulation, but only current...
This short-range circuit can act as a wireless microphone. We got the schematic and the printed...