HP 8924E, Assembly

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Appendix A, Error Messages
Self-Calibration Error Messages
N:\mkt\MANUALS\HP8924C\ALR\errmssg.fb
Self-Calibration Error Messages
Voltmeter Self Calibration Failed. Error = 223, 0x0000ffff (EXAMPLE)
The example noted above is one of many messages that may occur during self-calibration.
When the Test Set is powered up and at timed intervals for certain measurements, the Test
Set calibrates itself internally. Calibration usually takes 20 to 30 ms. The following
measurements are calibrated at these timed intervals:
• Voltmeter: approximately every 3 minutes
• Counter: approximately every 3 minutes
• Oscilloscope: approximately every 3 minutes
• Spectrum Analyzer: approximately every 4 minutes
Should a self-calibration fail, an error message is displayed. The error code (223,
0x0000ffff in the example above) will vary depending on the particular failure. Failures of
this type are generally caused by hardware. Since a general self-calibration occurs
immediately after power-up, these failures often appear as though they are power-up self-
test errors.
When a self-calibration failure occurs, check the A37 Measurement assembly first since
most of the measurement circuitry described above is located on it. However, in the case
of the spectrum analyzer calibration, check the A32 Spectrum Analyzer assembly first.
The A27 Reference assembly may also cause its own self-calibration failure or a
Spectrum Analyzer error message. (The error message in the example above can be
generated by unplugging the A27 Reference before powering up the Test Set.)
After displaying a self-calibration error message, the Test Set will proceed with the
measurement using default calibration factors. Depending on the nature of the failure,
subsequent measurements may look normal. The error message will persist.