This circuit was found in the magazine of radio amateurs 73 in a 90's edition. The components are current and the transistor is of general use.
This ohmmeter can be made with a scrap milliammeter used for continuity tests or even resistance...
This circuit was found in the November 1992 issue of Radio Electronics magazine. The circuit has...
Found in an English Maplin documentation from 1983, this circuit generates separate frequency...