Teletype 28 Adjustments

TELETYPE CORPORATION
SECTION 574-235-700TC
Skokie, Illinois, U. S. A.
Issue 5, April, 1965
28 AND 35 ANSWER-BACK UNIT
ADJUSTMENTS
CONTENTS PAGE
1.02 The adjustments in this section are ar-
ranged in a sequence that should be foi-
l.. GENERAL 1
lowed if a complete readjustment is under-
taken. A complete adjusting procedure should
BASIC UNITS 2
be read before attempting to make the adjust-
ment. After an adjustment is made, be sure
Trip Mechanism
to tighten any nuts or screws that may have
been loosened, unless otherwise instructed.
Armature extension gap 2
Clutch trip magnet armature spring 3
1.03 The adjustment illustrations indicate
Contact block position (final) 3
tolerances, positions of moving parts,
Contact block position (preliminary)
2
spring tensions, and the angle at which scales
should be applied. The tools required to make
Feed Mechanism
adjustments and check spring tensions are not
supplied with the equipment, but are listed in
Code drum contact wire spring 6
the appropriate section under separate cover.
Code drum detent spring 6 Springs which do not meet the requirements,
Eccentric stop position 5 and for which there are no adjusting proce-
Feed bail spring
4
dures, should be discarded and replaced by
Feed pawl
4 new springs.
Feed pawl spring 5
1.04 Where adjustment instructions call for
Relay Brackets and Contacts removal of components, assemblies,
subassemblies, or parts, all adjustments which
Motor hold and relay pull-up contact
the removal of these parts might facilitate
bracket 6
should be made before the parts are replaced,
Motor hold and relay pull-up contact 7
or as the equipment is reassembled. When a
Nonrepeat relay 7 part mounted on shims is removed, the number
and location of shims should be noted so that
Distributor Brushes
the identical pile-up can be made when the
part is replaced.
Brush holder spring
8
Distributor brush holder 8
1.05 All electrical contact points should meet
squarely. Contacts with the same di-
Gear Backlash
ameter should not be out of alignment more
than 25 per cent of the contact diameter. Check
Gear backlash - ASR (transmitter
contacts for pitting and corrosion and clean or
base) 10
burnish them before making the specified ad-
Gear backlash - RO, KSR 9
justment or tolerance measurement. Avoid
Gear backlash - self-contained unit . 9 sharp kinks or bends in the contact springs.
1. GENERAL
1.01 This section is reissued to add coverage
of the 5- and 8-level answer-back unit.
Since this revision is of a general nature, mar-
ginal arrows have been omitted.
Note: Keep all electrical contacts free of
oil and grease.
1.06 References made to left or right, up or
down, and front or rear apply to the
answer-back unit as viewed from the side with
© 1962 by Teletype Corporation
All rights reserved.
Printed in U-.S.A.
Page 1