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Defective
oscillator
removed
CLOCK
CHAIN
OSCILLATOR
LOCATION
0
1
2
3
TABLE B
033-21
033-56
133-21
133-56
Oscillator
power
removed
AND
AND
PWR OFF
lamp goes
[14] Disconnect
FREQ CONTROL INPUT
[15] Disconnect
D/A INPUT/OUTPUT
connector
J20
[16] Remove eight screws holding oscillator
[17] See WARNING 1. Remove oscillator
on
[13] Disconnect ground strap from
oscillator to frame upright
[12] Disconnect
RF OUTPUT
connector
P13
[11] Remove —48 volt fuse for oscillator
from network clock frame
mounting plate to frame
being removed [TABLE B]
oscillator being removed:
REMOVE DRO OSCILLATOR
P21
and
POWER INPUT
P19
connectors
remove power
ROS/OFF
switch is
in
ROS
position
At oscillator
[10] Depress
ROS/OFF
switch to
[9] Ensure chain OOS;
See TABLE A. At switch location associated with
OS
and
lamps go on
OFF NORM
CLOCK
CHAIN
POWER SWITCH
FRAME LOCATION
0
1
2
3
066-03
066-68
166-03
166-68
FUSE LOCATION
BAY
HMP
0
0
1
1
07
07
07
07
TABLE A
Defective units
are repairable
location only
at repair
SD-4A014-02
WARNING 1
DRO oscillator is
DC
DD
DC
DD
FUSES
fragile item.
DLP
234-151-013
DEC 1995
Issue 8
545
PAGE 2 of 3