AT&T 4 ESS, Руководство пользователя

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between 1.7 and
2.1 volts peak-
to-peak
No No
phase error
scope probe from
pack and connect probe
terminal 218 of
FB214
[SD-4A036-01]
AND
Page 9
Page 4
Yes
TABLE A
1 2 3
070-39
066-39
070-37
170-32
166-33
170-34
170-39
166-39
170-37
LOCATION
AND
to terminal 218 of
FB214
pack
[TABLE A] for chain having
of word 2 in response message
[13] Disable all 39B oscillators
[16] Connect channel 1 scope probe
[17] Is waveform
[22] Clear
[21] Remove channel 1
[20] Use binary results to determine
master clock chain [TABLE B]
CLEAR PHASE ERROR — 39B OSCILLATORS
5
DC
DC
DC
DC
MASTER
CLOCK CHAIN
oscillator
input terminal
FB213
master 003
0 1 2 3
002 201 001
TABLE C
pack [TABLES A and C]
to master oscillator
input terminal of
FB213
[14] See NOTE 4. Ensure chain
[15] See CAUTION 2. Calibrate
using the
STROBE
switch on
[12] At TTY, enter RMV:SCLK 0,NCSU 0 !
Improper scope
calibration may
affect service
Chains 2, 0
followed by 1, 3
out-of-service
errors in all four
this sequence:
or 3, 1 unless
chain other than 2
with diagnostic
failure, then clear
chain first
If clearing phase
NOTE 4
CAUTION 2
clock chains, follow
is out-of-service
BINARY BITS
DC DC
4 3 2 1 0
1 0 0
DC
DC
DC
DC
DC
1
0
1
0
1 0
0 0
0 0
MASTER
CHAIN
0
1
2
3
TABLE B
phase error cleared
DUMP:NCLK 0,CREG !
CLOCK CHAIN 0
070-32
066-33
070-34
CIRCUIT PACK
with phase error
FB213
FB214
FB687
each oscillator
is out-of-service
[18] Enter
scope [DLP-529]
[19] Convert rightmost two octal digits
to binary [Figure 1, Page 4]
234-151-013
Issue 8
PAGE 3 of 19
TAP
134
DEC 1995