Teletype 28 - Start Locklever Spring

SECTION 573-118-700TC
2. 12 Selector Mechanism (continued)
START LEVER
START LEVER
LATCHLEVER
SELECTOR RECEIVING MARGIN
START LEVER SPRING
Requirement
Latchlever spring unhooked. Stop
arm bail in indent of its cam. Range
~ ~ Min 2-1/2 oz---Max 4-1/4 oz
~
ale set at 60.
~ start stop arm moving.
STOP ARM
(Front View)
(1) Requirement (For Units Employing Armature With One Antifreeze Button)
When a signal distortion test set is available for determining the receiving margins of the
selector, and where the condition of the components is equivalent to that of new equipment,
the range and distortion tolerances below should be met.
(2) Requirement (For Units Employing Armature With Two Antifreeze Buttons)
When a distortion test set is available, the selector armature spring tension should be refined,
if necessary, to obtain satisfactory receiving margins. The front antifreeze button must
contact the magnet core when the magnet coils are energized.
To Adjust
Refine the SELECTOR ARMATURE SPRING (2.04 or 2.05) adjustment.
Current
0.060 Amp
(windings
parallel)
0.020 Amp
(windings
series)
0.035 Amp
(windings
series)
Page 22
SELECTOR RECEIVING MARGIN MINIMUM REQUIREMENTS
Speed in
WPM
60
75
100
60
75
Points Range
With Zero
Distortion
72
72
65 (45. 5 baud)
106 (75. 0 baud) 72
Percentage of Mark-
ing and Spacing Bias
Tolerated
40
40
40
End Distortion Tol-
erated With Sca.le at
Bias Optimum Setting
35
35
35