We found this version of the automotive tachometer in a 1980s publication. Variations from other sources appear elsewhere in this section. The indicator is a 0 to 1 mA milliammeter.
Microphones and other signal sources can be connected at the input of this circuit, with the 4.7...
This unusual unijunction transistor SCR firing circuit was found in a General Electric...
May 2016 - It can be obtained from Mouser Electronics new tricolors chipsLEDs from Broadcom for...