Teletype 28 - Selector Armature Spring

SECTION 573-118-?00TC
2. 04 Selector Mechanism (continued)
SELECTOR ARMATURE SPRING (Preliminary)
(For Units Employing Selector Armature With Single Antifreeze Button Only)
(1) Requirement
Witt,. locking levers and start lever on high part of their cams, scale applied aS' nearly
verUcal as possible under end of armature extension, it should require the following
tensions to move armature to marking position:
0. 020 and 0. 035 Ampere - Min 1-1/2 oz---Max 2 oz
0. 060 Ampere - Min 2-1/2 oz---Max 3 oz
Note:
This spring can be adjusted for maximum selector performance only when printer
is connected to the specific circuit over which it is to operate under service conditions.
Since there are several operating speeds and since circuits vary widely, it is impossible
to adjust spring for maximum performance at the factory. The foregoing spring tension
requirement is given to permit operation prior to measurement of receiving margins.
Readjustment made to obtain satisfactory receiving margin should not be disturbed in
order to meet requirements of this adjustment. The final spring tension should be held
as close as possible to the values given above, consistent with good receiving margins.
To Adjust
Position adjusting nut.
START LEVER
SPACING LOCKLEVER
(2) Requirement
ADJUSTING NUT
I:A' l ARMATURE SPRING
ARMATURE EXTENSION
MARKING LOCKLEVER
1 CAM
(Front View)
See
SELECTOR RECEIVING MARGIN(2.12) for final adjustment.
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