This circuit provides a 5 V negative voltage from a positive input voltage. Found in old American documentation, information on the used integrated circuit was not provided. Probably an oscillator.
This circuit is from 1993 documentation. The table provides the values of R3 and R4 according to...
This H bridge circuit can use medium power transistors up to 500 mA like BD135 and BD136 or for 2 A...
The idea of this interesting detector is to detect the changes in conductivity that occur with the...