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sure NOT to rotate it since this will reduce the signal level. At the
conclusion of the system test, return the FULL SCALE ADJUST
control back to the NORM position. Calibrate the full scale using a
3x5" (80x127mm) foil stretched between the electrodes. If the
sample is not flat, make sure it is static dissipative and adjust the
FULL SCALE ADJUST for a full scale reading. If the sample is
not static dissipative either wrap a specimen in foil or coat it with a
topical antistat to obtain the proper reading. Once this calibration
has been completed, DO NOT TOUCH THE FULL SCALE
ADJUST control.
After the SAMPLE CHARGE meter has been set contact ETS for
ZERO and FULL SCALE, the test procedure is followed as if a
normal sample were being tested. If testing is in the MAN mode,
depress the TEST button to obtain the calibrated DECAY TIME
reading. If in the AUTO mode, momentarily depress the CHG
button to start the test. In either case, the unit will go through the
usual test sequence and will display a DECAY TIME reading that
should be within ±0.05 seconds of the value indicated on the STM
System Test Module. Typically, for the STM-1 the decay time is
between 0.20 and 0.30 seconds. The difference between + and –
decay time readings should be no more than 0.02 seconds. If this
is the case, refer contact ETS for assistance.
3.3.4.2 STM-2 (Systems with Serial #878 or higher)
The STM-2 does not incorporate the banana plug. Install the
STM-2 directly into the electrodes in the Faraday Cage as shown
in Figure 3.2-1. The verification may be performed in either the
MANUAL or the AUTOMATIC mode. Select the appropriate test
mode and follow the test procedure outlined in Section 3.2 for the
MANUAL mode or Section 3.3 for the AUTOMATIC mode. In
either mode, the CUTOFF threshold should be set to 10% to
obtain the proper decay time reading. Set the SAMPLE CHARGE
meter to full scale in the CHARGE state (5.0kV). The FULL
SCALE ADJUST control should be in approximately the 12:00
o'clock position for a full scale reading on the SAMPLE CHARGE.
At the conclusion of the system test the system is now ready to
test a planer sample. If the sample is not flat, make sure it is static
dissipative and adjust the FULL SCALE ADJUST for a full scale
reading. If the sample is not static dissipative either wrap a
specimen in foil or coat it with a topical antistat to obtain the
proper reading. Once this adjustment has been made, DO NOT
TOUCH THE FULL SCALE ADJUST control.
After the SAMPLE CHARGE meter has been set to ZERO and
FULL SCALE, the test procedure is followed as if a normal
sample were being tested. If testing is in the MAN mode, depress
the TEST button to obtain the calibrated DECAY TIME reading. If
in the AUTO mode, momentarily depress the CHG button to start
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