Table 12 Display Signals - HP 54620A User's And Service Manual

Testing, Adjusting, and Troubleshooting the Analyzer
To troubleshoot the logic analyzer
Disconnect the display cable, then check the following signals on the
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system board, using an oscilloscope.
Table 12 Display Signals
HP 54620A Logic Analyzer
U3 Pin 7
U3 Pin 24
U4 Pin 2
HP 54620C Color Logic Analyzer
U34 Pin 18
U 39 Pin 21
U 34 Pin 2
If the signals are good, replace the display assembly. If not, replace the
system board.
Disconnect the LVPS ribbon cable from the display board.
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Measure the power supply voltages again (steps 2-4).
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If the voltages are within the test limits, replace the display assembly. If not,
do the steps below.
Disconnect the power cord.
a
Disconnect the ribbon cable from the power supply.
b
Connect the dummy load to the power supply connector.
c
Connect the power cord, then measure the power supply voltages
d
again, using a voltmeter (see new tolerances below).
+5.1 V (4.95 V to +5.25 V)
+15.75 V (+15 V to +16.5 V)
−15.75 V (−15 V to −16.5 V)
If the voltages are now within the test limits, replace the system
board. If not, replace the power supply.
166
Signal Frequency
DE 19.72 kHz
Hsync 19.72 kHz
CTD_Sync 60.00 Hz
Signal Frequency
DE 16.67 kHz
Hsync 16.67 kHz
CTD_Sync 50.0 Hz
Pulse width Voltage
38.0 µs
2.6 Vp-p
3.0 µs
5.0 Vp-p
50 ns 5.0 Vp-p
Pulse width Voltage
48.0 µs
5.0 Vp-p
2.9 µs
5.0 Vp-p
60.0 ns 5.0 Vp-p