Service manual

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Identifying
Defective Coil Assembly
This
procedure is intended to
identify which coil
assembly is defective, when a
check of ihe movement current
results in a zero current
reading, indicating
improper
I ii
ii
r. tinning of the
eJectrunic circuit.
Note:
Mechanical interference,
caused
by
improper
adjustment and/or any factor
(such as lint} which
restricts
or
work-loads the fork
may result in
abnormal
Tesl Set readings. Unless the
circuit is "open" (current
reads zero), it is
rarely
necessary to replace the
cuil assembly during repair
of
ACCUTRON. I!
the
tuning fork vibrates, an
ACCUTRON problem is not
due to a faulty
coil
assembly. Higher
than normal current or
variable current are (with
very rare
exception)
al waya caused by other factors.
Assuming
the Power Cell has
been checked and the Test
Set properly connected
to
Ihe
movement, yd
bhfl
meter
indicates
zero current, perform the
following simple test:
Remove the plug-Up
lead from the |ack in the
movement holder and touch it
to the
lead strap screw between
the two coil assemblies. The
defective (open)
coll
may be identified by
whether the current indicated by
the motor:
a. Remains
xero—Replace the cell coil
assembly
b. Becomes excessive-RepI ace
the
compnnent
coil assembly
INDD
NHEa
Checking Ihe Train
for I-'reedom
This
•
heck
in h'i.mI to il.ti-i nunc whether there is any
mechanical blockage of the
pa
ti.im
The roonl
scnnftlvp .mil convenient method of
checking the train
freedom is to
pluck,
M
twang" the line; of the tuning fork
to which the index
finger is atlachod.
When
this in done, the fork will
vibrato for a few
seconds and this
motion will be trans-
mitted to the train— if
it is not blocked.
The motion of the Iraln
can easily he seen by
watching any of the wheels at the
time
that the fork is being plucked. If
no motion of the gears Is
apparent when the fork
j*
plui kril, this in evidence ol n blocked
train, assuming that the indexing
linkage
ban already been
nliecked.
Tin- freedom of tho train may
BUM
bo checked by
simply moving one of
the whreln
with a tweezers
or needle with both pawl and
index collets
rotated lo disengage
the
respective jewels from Ihe index
wheel.
Hack Mechanism Inspection and
Adjustment
PAWL
PAWL
FINGER Lin PIN
1. Pull stem out (setting
position).
2.
Pawl jewel should be from
*4
lo
1
Jewel
thickness away
from index wheel. (Sec
Fig. 22.) If necessary adjust by
bending
pawl lift pin
Fig. 22
2Q