HP 8924E, Assembly

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Chapter 14, Diagnostics Descriptions
Description Of Audio Diagnostics (AFDIAGS3)
N:\mkt\MANUALS\HP8924C\ALR\diagnos.fb
The following values are also input to the DAC:
• 2047 (which gives the highest positive output)
• 2048 (which outputs 0 V)
• 2049 (which produces the negative of the value for 2047 and is sufficient to verify that
the output can accurately output a negative voltage)
• 4095
Note that the measurements are static (DC); an AC waveform should be accurate
if the DC values are correct. (Other tests will implicitly confirm this.)
The measurement limits are
±
10% of nominal
±
16 mV offset. To keep the test
simple, no attempt is made to check incremental stepping to improve accuracy at
low settings. Failure information is simple enough so that it is possible to pinpoint
the faulty assembly without elaborate diagnosis. The failure codes are as follows:
Table 115 Audio Generators 1 and 2 Failure Codes
Failure Codes Probable Cause(s)
Code 1 Suspect Signaling Source/Analyzer assembly (medium). (AFG1 Level Setting
DAC faulty.) Or Measurement assembly (medium) (Voltmeter multiplexer
problem.)
Code 2 Suspect Signaling Source/Analyzer assembly (medium) (AFG2 Level Setting
DAC faulty.) Or Measurement assembly (medium) (Voltmeter multiplexer
problem.)
Code 3 Suspect Measurement assembly (high) (Voltmeter problem.)