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screws holding rear of network
clock chain control cover
resistance
less than
1 ohm
Yes
No
[15] At rear of frame, install six
[14] At front of frame, install
network clock chain control
cover and retaining screws
[12] Is
repeat from
[11] Using ohmmeter, measure
resistance between pin 3 of
[17] Rotate
ROS/OFF
switch
position to restore clock
chain to service
counterclockwise to normal
and negative (—) terminal of
AND
AND
[10] Operate
PLS
switch
PLS
[13] Replace
PLS
switch and
CLEAR R1 OR PLS FAULT — 39B OSCILLATOR
lamps extinguish
extinguishes
PWR OFF
lamp
OS
and
OFF NORM
[16] Depress
ON
pushbutton to
restore power to clock
chain
PAGE 2 of 2
234-151-013
Issue 8
DEC 1995
TAP
128