17. Continue to hold the panel, turn on the unit by pressing the “ON” button. The display should
momentarily show ‘reset’. After a few seconds the displays should change and show ‘SI’ or
‘EG’ and ‘0.00’. With unit still “ON”, flip the reset toggle switch number 1 back to off.
18. Turn off the unit by pushing the “OFF” button.
19. Still holding the display panel, flip the calibration toggle switch number 2 to “ON”.
20. Turn on the unit by pressing the “ON” button. The display should show ‘cal’ and then the
permanent default calibration factor number. Leave the unit on and cal switch to “ON”.
21. Carefully re-insert the front display panel into the GeoGauge body. Screw back in each of the
four corners captive screws snug, not tight.
22. Five calibration measurements will be needed. The calibration factor number to be used will be
the average of the five. Use a watch or clock, to record when 90 seconds, plus or minus 5
seconds has elapsed between pressing of the “MEAS” button for each calibration measure.
23. Not touching the GeoGauge or platen except the indicated buttons, gently press the “MEAS”
button to begin the calibration measure #1. At the end of the calibration measure, record the
calibration factor as displayed on the panel. Press the saved button to save the value.
24. At 90 seconds from the previous press of the “MEAS” button, press the “MEAS” button again
to begin the calibration measure #2. At the end of the calibration measure, record the
calibration factor as displayed on the panel. Press the saved button to save the value.
25. Repeat each calibration measurements at 90 seconds apart for a total five times. More is not
necessary and will not improve the accuracy.
26. Save and record the fifth and last calibration measurement. Turn off the unit.
27. Remove the top display panel from the body, and flip the calibration toggle switch to “OFF”.
28. Reinsert the top display panel back onto the body and tighten the four captive Phillips head
screws at the metal corners snug.
29. Turn on the unit, the last saved calibration factor will be the temporary calibration factor until a
new programmed EPROM, with the average calibration factor burned in, is inserted.
30. Remove the GeoGauge from the calibration platen assembly and re-insert the three setscrews
into the ring foot using a “removable-type liquid locknut” or equivalent to secure the screws.
The top of the setscrews should be below the surface of the ring foot by about 1mm (1/32”).
To reinsert an EPROM, follow instructions from the EPROM insertion guide.
Humboldt Mfg. Co.
7300 West Agatite Avenue, Norridge, IL 60706 U.S.A.
Tel: 708-456-6300 Fax: 708-456-5412
