HP 85106D, Руководство пользователя

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HP 85106D mm-Wave System 4-21
Service and Troubleshooting
Check Unratioed Power Levels
On the HP 8510 press the following keys to check the IF signals indicated in
the following table.
{
USER 1 a1
} checks the a
1
incident IF signal
{
USER 2 b2
} checks the b
2
reflected IF signal
{
USER 3 a2
} checks the a
2
incident IF signal
{
USER 4 b1
} checks the b
1
reflected IF signal
NOTE
The maximum power level must not activate the
IF OVERLOAD
running error
message.
If Four Channels Fail
the Unratioed Power
Test
If the power levels on all four channels fail, the most likely cause of failure is
in the RF or LO source paths from the sources.
Remove the HP-IB and RF power cables from the HP 85106D system to
isolate the sources. Refer to the appropriate source manual to troubleshoot
the HP 8360 series sources. Be sure to check the power levels out of the
source and the RF cables from the sources to the HP 85106D system.
NOTE Do not try to measure the RF source power in source #1 of the HP 85106D
system by disconnecting the RF cable. Measuring the RF from the source
breaks the leveling loop and causes the source to supply maximum power
output. Instead, try placing a coupler in the RF cable path then measure the
power.
Consider substituting known good sources and cables for the suspected
sources.
If the sources are all good, then continue with “If One, Two, or Three
Channels Fail the Unratioed Power Test” on page 4-22.
Table 4-2 Typical Power Levels for Operational Check of the mm-Wave System
Frequency
Range 33 GHz to
50 GHz 40 GHz to
60 GHz 50 GHz to
75 GHz 75 GHz to
110 GHz
Band Q (WR-22) U (WR-19) V (WR-15) W (WR-10)
a
1
-13 -13 -26 -27
b
1
-15 -15 -27 -28
a
2
-13 -13 -26 -27
b
2
-15 -15 -27 -28