We found this circuit in an EDN from the 90s. The circuit is a voltage quadruplicator using operating equipment of the time. The output current is low.
This 1995 circuit uses interruption sensors or NC connected in series in any quantity. With the...
This circuit transmits the audio signals from a telephone line to an FM receiver placed nearby. The...
This circuit is from an old manual of operational amplifiers. The setting can be adapted to work...