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.
We found this circuit in a 1956 Sylvania publication. It serves to monitor telegraph transmissions being...
This small locator transmitter was found in old Radio Shack documentation. The transistor could be a...
This circuit can be implemented with any triac of the TIC series and the lamp must be...