This circuit tests the reverse voltage of power diodes. The transformer is high voltage and so are the rectifier diodes. The circuit is from a 1976 QST magazine.
This sophisticated circuit with two LF411 operational amplifiers appeared in the November 1984...
This circuit uses battery power, but it can be powered by an 80 to 200 V power supply, with no...
This interesting circuit, which can be used as an alarm, was found in a 1997 documentation. It...