This circuit was found in old documentation but uses components that are still common. The circuit can be used in logic from 5 to 12 V.
RF voltmeters can be tested with this circuit that generates a test signal. We found it in old...
This circuit is recommended by Texas Instruments in the datasheet of the TL317, equivalent to...
This circuit for incandescent lamps was found in an American documentation from the 80s. The...