Geonics Limited EM38-MK2, Руководство по эксплуатации

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EM38-MK2 GAIN CALIBRATION PROCEDURE
The following is the Gain Check and calibration procedure for EM38-MK2 using the test coil
and test jig.
1. Set the EM38-MK2 in the jig with the test coil as per figure 12. Make sure that the
test coil is switched off.
2. Set the Mode switch to I/P position and adjust the I/P component to zero.
3. Set the Mode switch to Q/P position and adjust the Q/P component to zero.
4. Turn the test coil on. The instrument should read approximately 90 mS/m for 1 m coil
separation and 185 mS/m for 0.5 m separation. If the reading deviates more than
± 4 mS/m and ± 8 mS/m for 1 m and 0.5 m separation respectively, adjust the gain
with potentiometer # R14 (inside the instrument) to obtain the optimal readings
5. Set the Mode switch to I/P position with the test coil off. Adjust the I/P knobs to
obtain zero I/P reading.
6. Turn the test coil switch on. Inphase readings should read 90 ± 4 mS/m and
186 ± 8 mS/m for 1 m and 0.5 m coil separation respectively. There is no separate
gain adjustment for I/P components.