HP 8560E Service Manual page 366

e. Set the pulse/function generator to NORMAL mode with a duty
cycle of 50% and a frequency of 10 Hz.
f. Press the following keys on the oscilloscope:
CLEAR DISPLAY
off frame axes grid
connect dots off on
TRIG
source 1 2 3 4
.............................................................................. 2 V
level
TIMEBASE
TIMEBASE
CHAN
CHANNEL 1 2 3 4 off on
CHANNEL 1 on
set V/div to 0.2 V and offset to 0.6 V (10:1 probe used)
CHANNEL 4 on
set V/div to 2 V and offset to 0 V
DISPLAY
DISPLAY norm avg env
g. Using a 10:1 probe connected to channel 1 of the oscilloscope,
check for activity at pins 10 and 13 of A3U617.
h. If either pin (or both) show no activity, check for activity at pin 21
(LTIMER) of A3U617.
i. If LTIMER is not active, troubleshoot the Interface Strobe Select
circuitry (block K).
j. If there was activity at pins 10 and 13 of A3U617, suspect
A3U616.
Chapter 7
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......................................................... 50 ms/div
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ADC/Interface Section
Triggering or Video Gating Problems
grid
on
norm
4
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