Keithley 2015, Service Manual

Page: 57 / 158

2-24 Calibration
Manufacturing calibration
The manufacturing procedure is normally performed only at the factory, but the necessary
steps are included here in case the unit is repaired, and the unit requires these calibration
procedures.
NOTE If the unit has been repaired, the entire comprehensive calibration procedure should
also be performed in addition to the manufacturing calibration procedure.
Recommended test equipment
Table 2-15 summarizes the test equipment required for the manufacturing calibration steps.
In addition, you will need the calibrator and signal generator (see Table 2-1) to complete the
comprehensive calibration steps.
Table 2-15
Recommended equipment for manufacturing calibration
Unlocking manufacturing calibration
To unlock manufacturing calibration, press and hold in the SOURCE key while turning on
the power.
Measuring synthesizer signal amplitude
The 3Hz synthesizer signal amplitude must be accurately measured using the digital multim-
eter listed in Table 2-15. Proceed as follows:
1. Connect the synthesizer output to the digital multimeter INPUT jacks. (See Figure 2-7
for typical connections.)
2. Turn on the synthesizer and multimeter, and allow a one-hour warm-up period before
measuring.
3. Set the synthesizer to output a 1V RMS sine wave at 3Hz; measure and record the signal
amplitude.
Keithley 3930A or 3940 Frequency Synthesizer:
1V RMS, 3Hz, ±5ppm
1V RMS, 1kHz, ±5ppm
Keithley Model 2001 or 2002 Digital Multimeter:
1V, 3Hz AC, ±0.13%
Keithley Model 8610 Low-thermal short