We found this battery eliminator in a Radio Electronics magazine from August 1974. The transistor must be equipped with a heatsink and other voltages can be achieved by replacing the zener.
This latching alarm circuit using relays was found in American documentation. Sensors are...
Pressing and releasing S1 remains one of the neon lamps. Which one will be, it is not possible to...
Found in an Electronic Design, this small power source uses a battery as a voltage reference,...