AT&T 4 ESS, Руководство пользователя

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-3V
0V
CHECK DS1 SYNC REFERENCE SIGNAL
for symmetry and amplitude
[NOTES 1 & 2]
+3V
Vert = 2V/DIV, Horiz = 0.1
µ
s/DIV
sync coordinator
for assistance
No
attach probe ground to pin 090
[6] At terminal block 052-03, move
probe ground to pin 092 and
scope probe to pin 093
AND
[4] Does
waveform
resemble
AND
waveform
resemble
[8] Does
[5] Contact
sync coordinator
for assistance
No
Yes
Yes
[1] See CAUTION 1. Calibrate
and scope probe to pin 091
[2] At terminal block 052-03,
[9] Contact
for symmetry and amplitude
CAUTION 1
calibration may
affect service
NOTES
1. Symmetry may vary
slightly depending
on cable lengths
and grounding
conditions
2. Amplitude limits
are 3.5V p-p
minimum and 8V p-p
maximum
Improper scope
0
[NOTES 1 & 2]
scope [DLP-529]
[7] See Figure 1. Observe waveform
Figure 1 — Typical DS1 Sync Reference Signal
Figure 1
[3] See Figure 1. Observe waveform
Figure 1
234-151-013
550
DLP
PAGE 1 of 1
DEC 1995 Issue 8