Teletype 28 Disassembly And Reassembly

TELETYPE CORPORATION
Skokie, illinois, U.S. A.
SECTION 573-133-702TC
Issue 2, June, 1966
28 ELECTIDCAL SERVICE UNITS
DISASSEMBLY AND REASSEMBLY
1. GENERAL
1. 01 This section provides disassembly and
reassembly instructions for 28 electrical
service units used in teletypewriter sets. It is
reissued to provide additional information in a
standardized format. Since this is a general re-
vision, marginal arrows ordinarily used to indi-
cate changes and additions have been omitted.
1. 02 When it is necessary to remove the var-
ious components from the electrical
service unit, the appropriate wiring diagrams
should be used as a reference.
1. 03 After the disassembly procedure has been
followed, reassembly procedure for most
components is obviously a reversal of the dis-
assembly procedure. Where necessary, reas-
sembly information is given.
Note: Remove power from unit before starting
disassembly procedure. ·
2. DISASSEMBLY AND REASSEMBLY
2. 01 Removal of 28 Electrical Service Unit
from 28 Teletypewriter Cabinet used with
28 KeyboardSend-Receive (28 KSR) or Receive-
Only (28 RO) Teletypewriter.
(1) Raise dome of cabinet and disconnect all
plugs and receptacles from the typing
unit.
(2) Remove the typing unit in accordance with
the section entitled "28 Typing Unit, Dis-
assembly and Reassembly. "
(3) Disconnect all plugs and receptacles from
the keyboard and remove the keyboard.
( 4) Remove the mounting studs from each end
of the electrical service unit.
Note: The electrical service unit may now
be turned upside down for servicing or un-
wiring components.
(5) The various components may be removed
from the unit by removing their mounting
screws on the top side of the unit and dis-
connecting cabling and wires.
( 6) · If it is desirable to remove the electrical
service unit completely from the cabinet,
disconnect the remaining wires and cables.
2. 02 Removal of Electrical Service Unit from
Skin- Tight KSR Sets (Located behind the
typing unit cover):
(1) Unlatch electrical service unit cover at
each end and lift cover off.
(2) Remove the mounting studs from each
end of the electrical service unit and lift
unit off base.
(3) Remove various components from the
electrical service unit by removing their
mounting screws and disconnecting wire or
cable connections as necessary.
2. 03 Removal of 28 Electrical Service Unit
from 28 Automatic Send-Receive Sets
(28 ASR):
(a) \Vithout auxiliary equipment
( 1) Raise the dome of the cabinet and dis-
connect all plugs and receptacles from
the typing unit.
(2) Remove the typing unit in accordance
with the section entitled "28 Typing
Unit, Disassembly and Reassembly. "
(3) Disconnect all plugs and receptacles
from the perforator- transmitter base.
( 4) Remove the mounting studs from each
end of the electrical service unit.
(5) Remove the power control switch as-
sembly bracket at the right end of the
unit and the line- test- key control assembly
at the left end.
( 6) Remove various components from the
electrical service unit by removing
their mounting screws and disconnecting
wire or cable connections as necessary.
© 1966 by Teletype Corporation
All rights reserved.
Printed in U.S. A.
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