This high voltage source, found in 90’s Popular Electronics, can reach tens of thousands of volts. The Q2 transistor must have an excellent heat sink and the 9 V source is high current.
This circuit shows how to use common logic functions to divide a frequency by 7. The output signal...
This circuit can be used in alarms, data links or áudio links using IR radiation. The circuit is...
This circuit was obtained from an American 80's documentation. It can be implemented with modern...