Agilent Technologies HP 8719D Service Manual page 243

Broadband Power Problems
This section assumes that a power problem exists across the full frequency
range, and that no error message is displayed. The problem may affect port 1,
port 2 or both. Suspect assemblies include:
To also troubleshoot port 2 problems, press m l&&l :;...JEV -2:! :(I#&) .
Press
2. Choose which port to begin troubleshooting by pressing m and
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3. lb Disable the ALC eliminate modulator control, press C-J
power meter to measure the power at the faulty port:
4. For the HP 8719D/20D:
If you measure at least + 5 dBm (+ 10 dBm, Option 007) at the port:
n
replace the A59 source interface board assembly.
If you measure less than + 5 dl3m ,(+ 10 dBm, Option 007) at the port:
n
measure power at the other port:
If you measure less than + 5 dBm (+ 10 dBm, Option 007) at the other port:
n
continue with "A69 Step Attenuator Check" next.
If you measure at least + 5 dBm (+ 10 dBm, Option 007) at the other port
n
either the directional coupler or the bias tee or the transfer switch (S4)
is faulty. The power loss through each of these components should be
negligible.
(Option 400 Only)
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Source Troubleshooting 7-23