We found this circuit in a Radio Electronics from October 1976. The components are still common, but the circuit applies to older car models with contact breaker ignition.
This circuit was found in the August 1970 issue of Radio Electronics magazine. It employs RCA's...
This circuit is from 1968 General Electric documentation. It can certainly be adapted for any...
This tachometer from a 1994 publication has a bargraph scale with the well-known LM3914 integrated...