Troubleshooting; General Information - Fluke 9100 Series Service Manual

3. Place the bottom half of the module (with the PCAs still attached)
with the mainframe cable facing you. Remove the two Phillips screws
on the corners of the PCA closest to the mainframe cable that hold
the PCAs to the bottom of the case. Pull the PCAs away from the
lower half of the case.
4. To separate the PCAs, turn the the PCAs component side down. Remove
the three Phillips screws (two on the corners of the PCA furthest
away from the mainframe cable and one in the center of the board)
that hold the PCAs together. Carefully pull the boards apart to
avoid damage to the connectors.

TROUBLESHOOTING

This section contains general troubleshooting information that isolates
the problem to one of the Vector Output I/O Module PCAs. For more
complete information on testing and troubleshooting, along with software
to supplement the tests, a 9100A Service Kit (John Fluke Part Number
818948) can be purchased.

General Information

If the Vector Output I/O Module fails the self test, the PCA that failed
can usually be quickly isolated. To verify that the output section is
driving out any vectors, place the 9100A single-point probe on the
module output connector (J1 and J2 on the Top PCA).
If the module is not driving out vectors, check the following few key
signals on the Top PCA (9100A-4022) on the affected channel(s) while the
self test is being performed:
o Verify the non-assertion of the external TRISTATE- signal on pin 1
of the 74AC273 D-Type Flip-Flops (U101, U103, . . .) of the Pattern
RAM Functional Block.
o Verify the activity of the LAT-CLK signal on pin 11 of the 74AC273
D-Type Flip-Flops (U101, U103, . . .) of the Pattern RAM Functional
Block. If these signals are not active, verify that the SSGATE-
output of the 74AC20 (U12) is low. If it is not low, check the
inputs to U12 to determine which condition is preventing clocking.
If the module is driving out vectors, but failing the self test, the
Main PCA (9100A-4021) can be used for stimulus measurement with the Top
PCA removed. Another module may be used to stimulate the failing
channel(s) by connecting its output to the Main PCA input connectors J2
and J3 while the single-point probe is used to trace the signal paths.
The failure mask of the self test can often provide clues as to whether
the input or output section failed. The failure mask is displayed as a
10-digit hex value. Each channel of the Vector Output I/O Module is
displayed as one bit of the mask (for a total of 40 channels). On the
input section of the module, each custom chip (U100, U110, U120, U130,
and U140 on the Main PCA) has eight channels. On the output section,
each RAM chip (U100, U102, U200, U202, U300, U302, U400, U402, U500, and
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3/Maintenance