Keysight Technologies N5247B, Service Manual

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Keysight N5247B Service Guide 4-45
Troubleshooting
Measurement System Troubleshooting
Checking the A7, A8, A12, and A13 40 GHz Doubler Outputs
1. Refer to the block diagram at the end of this chapter and to “Top Cables,
All Cables—All Options, S/N Prefixes <6021” on page 6-21 . Locate cable
W11 on the A7 doubler board, cable W17 on the A8 doubler board, cable
W13 on the A12 doubler board, and cable W15 on the A13 doubler board.
(A12 and A13 are only available in 4-port models and 2-port models with
Option 224.)
2. Disconnect cable W11 or W17 or W13 or W15, dependent on which
doubler board is to be checked.
3. Connect the spectrum analyzer to the open connector on the doubler
board to be checked.
4. Set the network analyzer for an 800 MHz CW frequency and observe the
spectrum analyzer measurement. An 800 MHz signal should be present.
5. Refer to the NOTE notice on page 4-29 . If the observed problem was
frequency banded rather than broadband related, set the analyzer
frequency to the center of the problem band. The spectrum analyzer
should measure a signal above the network analyzer setting. For analyzers
with DSP version 4.0, the signal is 7.61 MHz above the network analyzer
setting. For analyzers with DSP version 5.0, the signal is 7.44 MHz above
the network analyzer setting.
6. If the signal is not present but the signals from “Checking the A4 and A17
Source Synthesizer Outputs” are present, replace the appropriate doubler
board. Refer to “Removing and Replacing the A4–A17 Boards” on
page 7-18 .
7. If the signal is present, reconnect all cables, and then continue with
“Checking the Signal Separation Group” on page 4-47 .
Checking the A60, A61, A62, and A63 70 GHz Doubler Outputs
1. Refer to the block diagram at the end of this chapter and “Bottom RF
Cables, 4-Port, Option 423 with and without 029 (Ports 1 and 2), S/N
Prefixes <6201” on page 6-108 , “Bottom RF Cables, 4-Port, Option 423
with and without Option 029 (Ports 3 and 4), S/N Prefixes <6201” on
page 6-113 or to “Bottom RF Cables, 4-Port, Option 423 with and without
029 (Ports 1 and 2), S/N Prefixes ≥ 6201” on page 6-161 , and “Bottom RF
Cables, 4-Port, Option 423 with and without Option 029 (Ports 3 and 4),
S/N Prefixes ≥ 6201” on page 6-166 . Locate the following cables. (Boards
A61 and A62 are available only in 4-port models and 2-port models with
Option 224.)
— W27 on the A60 doubler board,
— W28 on the A61 doubler board
— W29 on the A62 doubler board