We found this circuit in a Poptronics from 1998. The circuit can be extended to more competitors with another 4011. The power can be made with voltages from 6 to 12 V.
This circuit, which can only be used with incandescent lamps, is adapted to the common wall...
Audio frequencies in the 300 Hz to 30 kHz range can be measured with this circuit. Transistors allow...
In the event of a short in the output, the relay disarms interrupting the supply. To reset this...