Troubleshooting When One Or More Inputs Look Good - Agilent Technologies 8753ES Option 011 Service Manual

Troubleshooting When One or More Inputs Look Good

Since at least one input is good, all of the common receiver circuitry beyond the
multiplexer is functional. Only the status of the individual sampler/mixers and their
individual signal paths is undetermined.
Check the 4 kHz Signal
1. Connect a cable from the RF OUT port to input R.
2. Press
Preset Menu
3. Use an oscilloscope to check the 4 kHz output of the sampler/mixer in question at the
A10 assembly. The input and output access pins are listed in
should resemble the waveform of
• If the signal is good, continue with
Constants Off" on page
• If the signal is bad, skip ahead to
page 8-12.
Table 8-2 2nd IF (4 kHz) Signal Locations
Mnemonic Description
IFR 4 kHz
IFA 4 kHz
IFB 4 kHz
Figure 8-6 2nd IF (4 kHz) Waveform
Chapter 8
.
CW FREQ
Figure 8-6.
"Check the Trace with the Sampler Correction
8-12.
"Check 1st LO Signal at Sampler/Mixer" on
A10 Location Signal Source
A10P1-1, 31 A4P1-6
A10P1-4, 34 A5P1-6
A10P1-7, 37 A6P1-6
Troubleshooting When One or More Inputs Look Good
Table
Receiver Troubleshooting
8-2. The signal
8-11