Teletype 28 Adjustments

BELL SYSTEM PRACTICES
Plant Series
SECTION 573-133-700
Issue 2, July, 1966
AT&TCo Standard
28 ELECTRICAL SERVICE UNITS
ADJUSTMENTS
CONTENTS
PAGE
1. GENERAL .................. .
2. REQUIREMENTS AND
ADJUSTMENTS .............. .
Electrical Motor- Control
Mechanism
Intermediate lever spring . . . . . ...
Start armature spring . . . . . . . . . . .
Start magnet core. . . . . . . . . .... .
Stop armature spring .......... .
Line Test Key Assembly ........ .
Relay Motor- Control Mechanism
Inner contact spring gap ........ .
Middle contact spring .......... .
Outer contact spring . . . . . . . . . . . .
Switch position. . . . . . . . . . . . . . . .
Signal Bell
Armature spring
1
2
3
3
3
3
5
4
4
4
4
5
CONTENTS PAGE
Remote signal bell . . .......... . 5
28G and 28G-1 Electrical
Service Units
Slow release relay ............ . 2
28LB Electrical Service Unit . . . . . . 6
1. GENERAL
1. 01 This section provides mechanical adjust-
ing information for the 28 electrical
service units and most of the various components
that may be assembled onto it. It is reissued to
include a signal bell assembly and to arrange
the material in a standardized format.
Note: Remove power from units, before
making adjustments.
1. 02 Since this is a general revision, margi-
nal arrows normally used to indicate
changes and additions have been omitted.
Prepared for American Telephone and Telegraph Company by Teletype Corporation
© 1966 by Teletype Corporation
All rights reserved.
Printed in U.S. A.
Page 1