This 1-transistor circuit for currents up to 50 mA was found in the August 1974 Radio Electronics magazine. The transformer is 50 to 200 mA.
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,...