This circuit for audio applications was found in an English magazine from the 80's. The circuit has a pass band below 3 kHz making it ideal for telecom applications.
This 2004 circuit is based on the ionization effect that occurs in old incandescent lamps with...
This bidirectional current sensing circuit was found in a 2005 Linear Technology application manual....
This circuit can be used in decoration or to draw attention, in a “fake” assembly for example. What he...