Tektronix WFM8200, Руководство по обслуживанию

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General Maintenance
Run Advanced Diagnostics To run the Advanced diagnostics, press the CONFIG button, then select Utilities
> Run Advanced Diags .
Advanced Diagnostics includes tests that check interfaces between FPGAs and
memory on the Main board. If any of these tests fails, replace the Main board.
Isolating Lissajous Display
Errors
The audio Lissajous phase display uses a serial data path between the audio and
main boards. A failure in this data path can be due to a problem on either board.
Perform the following tests to isolate the problem to one board or the other.
1. Prepare a test oscilloscope with the following settings:
Control Setting
Vertical Scale 2.00 V/div
Horizontal Scale 200 ns/div
2. Check the Lissajous bus clock by performing the following substeps:
a. Put the oscilloscope probe on pin B3 of connector J641 on the audio
board. Verify the signal is
≈ 3 V
p-p
and is a continuous 50% duty-cycle
squarewave.
b. If the signal at J641 is not as described in step a, the audio board most
likely has a failure; otherwise, replace the main board.
3. Check the Lissajous bus frame and data signals by performing these substeps:
a. Put the oscilloscope probe on connector J641 pin B2 of the audio board
and verify the signal is
≈ 3 V
p-p
and toggles low at regular intervals.
b. If the signal on pin B2 looks OK, put the oscilloscope probe on pin B4.
Pin B4 is the data line and the signal will have a somewhat random look
depending on the audio source. Just verify that the signal is toggling and
is
≈ 3 V
p-p
.
c. If either signal looks bad at J641 the audio board most likely has a failure,
otherwise replace the main board.
Option EYE/PHY
Troubleshooting
The EYE/PHY functions depend on the EYE and Main boards, and the
interconnections between them.
Major Operational or Diagnostic Failure.
Check that the 110 pin CPCI connector between the Eye and Main boards is
correctly seated and secure.
Check that the ribbon cable from the Eye board to the main board is securely
plugged into J5 on the eye board and J16 on the main board.
4–18 WFM8200 and WFM8300 Waveform Monitors Service Manual