Using a master tach, determine the actual enginerpm. Adjust the
selector switch for gross calibration (close to actual
engine rpm).
Using the proper calibration tool (see instrument label), turn the
calibration "pot" until actual
engine rpm is indicated.
After the fine calibration (a few seconds after the final adjustment),
the tach will automatically reset (pointer will sweep around) and
save the calibration set point, indicating a complete calibration.
If the unit does not display the actual engine speed, repeat the
above calibration steps.
➥
http://gilmore-global.com/howto_guid...structions.pdf