Keithley 610C, Instruction Manual

Page: 33 / 44

b. Set the Model
241
to zero volts, release the
Electrometer ZERO CHECK Button and note that the Model
662
null remains the same.
1.
Apply
+100
volts to the Model 6l0C input with
the Voltage Supply. The Differential Voltmeter null
indication should not change more than
1
millivolt,
indicating a unity gain within
10
ppm.
2. Repeat the test of subparagraph 1 above using
-100
volts.
6-13.
FREQUENCY RESPONSE CHECK.
a. Zero check the unit. Connect a Wavetek Model
102
Function Generator through a
1000:1
divider to the
Model GlOC input and connect the Electrometer output"
to a Hewlett-Packard Model
400
AC
VTVM.
Set the Elec­
trometer FEEDBACK Switch to NORMAL.
b. Zero the Model
610C
on the
10
millivolt range.
1.
Set the Signal Generator to
20
Hz at minimum
output. Release the Electrometer ZERO CHECK Button
and increase the Generator output to obtain 2 volt
rms at the Model GlOC output.
2. Set the Generator to 100 Hz. The Electrometer
output voltage must be within
±3
dB of the
20 Hz 2
volt rms output.
c. Zero the Model
602
on the 3 volt range and change
the divider to
100:1.
1.
Set the Generator to
100
Hz and for mlnlmum
output. Release the ZERO CHECK Button and increase
the Generator output to obtain
0.1
volt rms at the
Electrometer output.
2.
Set the Generator to
40
kHz. The Model
6l0C
output must be within ±3 dB of the
100
Hz
0.1
volt
rms output.
NOTE
If other than a constant amplitude signal
generator (Wavetek) is used, it will be
necessary to monitor the output of the
Signal generator with another
VTVM
in
order to maintain the same signal level
at various frequencies specified.
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