Wav files for Tachometer calibration

from the column for your engine type choose an RPM somewhere near the middle RPMs

download the Wav file from that line in the table (right click and "save link as")

connect power and ground to the Tachometer

connect the red calibration lead clip to the tachometer calibration input

connect the black calibration lead clip to the tachometer case

connect the other end of the cable to your laptop, computer, iPhone etc.

 No other cables should be connected ..  eg no connection to the car ignition system

With the tachometer in the orientation it will be in the car

Play the wav file at full volume, (if using windows media player, select "loop" to play the file continuously)

the tachometer should respond

adjust the tachometer to show the appropriate RPM in the table


  Frequency      4 Cyl        5Cyl        6Cyl        8Cyl       10Cyl       12Cyl   
  50Hz 1500 1200 1000 750
  100Hz  3000    2400    2000    1500    1200   1000
  200Hz  6000    4800    4000    3000    2400   2000
  300Hz  9000   7200    6000    4500    3600   3000
  400Hz     9600    8000    6000    4800   4000
  500Hz     10000    7500    6000   5000
  600Hz         9000    7200   6000
  alt 100+200Hz
  alt 100+200+300Hz


The latest instructions for installing our RVI to RVC board can be found here

An FAQ with further useful information can be found here


If the tachometer does not respond to playing the wav file then you can try the following

increase the volume on the device playing the file

try with various combinations of bass and treble (tone)

try switching the red and black calibration wire connectors.

the sensitivity of every board is tested using a standard signal, so don't give up,

If the the board tries to make the needle move the wrong way..   you will need to switch the thin red and black wires



Videos of the tachometer kit on YouTube
RVI to RVC 1 dismantling the tacho
RVI to RVC 2 fitting the circuit board
RVI to RVC 3 powering up the board
RVI to RVC 4 calibrating
RVI to RVC 5 alternative connections


 the external resistor mentioned in the videos is no longer required


Checking calibration with an acoustic tachometer

For calibration on the car, a simple (although not always successful) alternative to a rolling road is to use a smartphone acoustic tachometer app.
We have tried two android apps (We have no affiliation or connection with these products) with varying degrees of success !


Generating your own calibration signal

a customer found this androiud app useful, generating a useable tone when the downloaded wav files did not work well.

and the equivalent for a PC
Copyright © 2017 Spiyda Ltd. All rights reserved. Registered office - 54 Bridgnorth Road, Stourbridge. DY8 3QG. Registered in England and Wales, Company Registration Number 10511733