HP 8924E, Assembly

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Chapter 2, Troubleshooting
More About Step 1- Run the Power-Up Diagnostic
N:\mkt\MANUALS\HP8924C\ALR\trouble.fb
Miscellaneous Diagnostics (MSDIAGS3)
This program verifies the following:
• The ability of the A27 Reference to detect the presence of the A29 CDMA Reference
signal and its ability to lock to that signal.
• The integrity of the front-panel RF IN/OUT, DUPLEX OUT, and ANT IN connectors.
• The Self-Test Diagnostics, and power supply voltages. The Self-Test Diagnostics are
described in detail in
"Description Of Self-Test Diagnostic" on page 541 .
• Serial bus communication
The Miscellaneous Diagnostics cannot be run in a loop mode.
CDMA Diagnostics (CDMADIAG)
This program tests the following parameters:
• CDMA Reference (A29): 20MHz VCXO tune voltage and phase-lock status,
19.6608MHz VCXO tune voltage and phase-lock status, and AWGN (noise) source’s
status.
• LO/IF Demod (A31): 117.9864MHz local oscillator (LO) bias and tune voltage,
3.686MHz IF sense, 114.3MHz IF sense, Spectrum Analyzer path sense, supply
voltages references, and IQ Demodulator LO tune voltage and sense.
• IQ Modulator (A25): RF Input detection, IQ output detection, baseband I and Q
detection, I signal gain, various modulator control levels.
• Cell Site Analog (A8): Cell Site 1&2 video DAC references, Cell Site 1 I and Q gain
control DAC voltage, I and Q summing amplifier outputs.