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.
This circuit was found in a 1986 publication. However, it can still be easily assembled, as the...
This circuit was published in Radio Electronics magazine in June 1959. The circuit uses an...
This circuit is based on an old Siemens integrated that can now be found very easily. It allows the...