Bell 503-100-120 Service Manual

BELLSYSTEM PRACTICES SECTION 503-100-120
AT&TCo Standard Issue 4, August 1978

581A TELEPHONE SET BASES

1. GENERAL • Cord, mounting, D10R-* (specify length)

1.01 This section contains identification, installation, 1A2 KTS and 3B (MD) or 4-type speakerphone]

connections, and maintenance information

for the 581A telephone set bases. The 581A • Dial, 6TA (Chrome)t or 6UA (Gold)t
telephone set base (Fig. 1), component parts furnished

with the base and a 6TA or 6UA rotary dial (Fig. 2), • D-180460 Kit of Parts (TOUCH-TONE ®dial).

ordered separately, are designed for assembling

into a customer-supplied housing and handset. * Add appropriate color suffix.

1.02 This section is reissued to: t Includes card holder assembly and three (3)

• Add D-180778 kit of parts (modular mounting

cord jack) 2.02 Optional Apparatus or Equipment

• Add 840401723 inside connector and 840401731
outside connector • D-180409 Kit of Parts (241B Amplifier)

• Revise Fig. 1, 2, 3, 4, 6, 9, 11, 12, 14, 16, • D-180461 Guard Assembly (Polarity Guard).
17, and 18

• Add Fig. 5, 8, 10, 13, and 15

• Revise Tables A through G operative telephone circuit when properly

• Add Tables H and I and handset

Since this reissue covers a general revision, arrows • Components provide a single line, rotary or
ordinarily used to indicate changes have been TOUCH-TONE dial telephone set

omitted.

2. ORDERING GUIDE

Base, Set, Telephone, 581A (Fig. 1)

2.01 Associated Apparatus or Equipment housing to accept standard components. The
(ordered separately): premises must be wired with an appropriate

• Cord, Mounting, D4BU-29 D4BU-29 plug-ended mounting cord.

[when rotary dial set is used with 1A1 or

screws (Fig. 2).

(ordered separately):

2.03 Features:

• Standard components which provide an

assembled within an appropriate housing

• Provisions to add 241B amplifier, TOUCH-TONE
dial, and polarity guard (optional).

3. INSTALLATION AND CONNECTIONS

3.01 The customer's housing must be an acceptable

connecting block or jack in order to accept the

• Cord, Handset, H4CJ-*, 6 feet Acceptable Telephone Set Housings

• Cord, Mounting, D6AA-* (specify length) 3.02 Older acceptable housings carry an acceptance

(required when candlestick type telephone stamp located on bottom which reads "This
is installed) Enclosure Conforms To Drawing B-69650r'. Space

NOTICE

Not for use or disclosure outside the

Bell System except underwritten agreement

Printed in U.S.A. Page 1

SECTION 503-100-120

i

4228 NETWORK LINE SWITCH P1A RINGER

1 623P4 JACK ._ _._., 5

2 3 "_" 4

LEGEND

1 -- 581A Telephone Set Base 7- 840153274 Lead Assembly (BK) Required for Desk
2- U3 Receiver Unit 8- 840153290 Lead Assembly (R) Ca_diestick Set O_ly

3-- T1 Transmitter Unit
4 - 840401723 Connector Inside
5- 84041731 Connector Outside
6- 840401673 Screw(s) loose and packaged as parts group 840151054° Dial

Page 2

Note: The _'eceiver and transmitter units are shipped
loose with base. Items 4 through 8 are also shipped

must be ordered separately.

Fig. 1_581A Telephone Set Base and Parts Group

/6

8

ISS 4, SECTION 503-100-120

Fig. 2m6TA or 6UA Dial and Associated Parts

for the reviewing telephone companys name and must be removed prior to installation of
their assignment number is also provided. Newer telephone company parts and returned to the

housings carry the marking "Bell System Identification customer.
#. This enclosure conforms to Bell System Voice

Communication Technical Reference CAK." Nonconforming Housings

Note: Inspect the customer's telephone set 3.03 Housings which do not carry the acceptance
components before accepting them for service, stamp or identification number must be
Be sure he is aware of any missing or defective modified by the local Western Electric Service

components found. All components and wiring Center to accept these standard Bell System
furnished as part of the customer's housing components. Components and wiring removed by

Page 3

SECTION 503-100-120

the service center should be returned to the 3.06 TOUCH-TONE Dial (D-180460 Kit
customer, of Parts), ordered separately.

Assembly (Desk Set Type) (1) When the customer's antique-decorator housing

3.04 Install 581A Telephone Set Base as service, install a D-180460 Kit of Parts.
follows.

(1) Remove upper housing from base of

customer-owned housing. 3.07 If a polarity guard is required in conjunction

(2) Position 581A telephone set base on base D-180461 guard assembly, which consists of guard

of customer's housing, ensuring that the assembly, brackets, screws, and a printed wiring

ringer volume control is accessible through opening board assembly. The polarity guard is installed
of base. when specified by local instructions for end-to-end

(3) Fasten 581A base using four screws, furnished are encountered. Refer to Fig. 4 for location and

with set or screws furnished with the Table C for connections.

housing. A typical installation in a customer-owned
desk set type housing is shown in Fig. 3. 3.08 Mounting cord (ordered separateIy)

3.05 Rotary Dial (ordered separately). Kit of Parts.

(1) Install 6TA (chrome) or 6UA (gold) dial

(Fig. 2) using three screws furnished with _'_n_ New 581A bases come equipped with

dial. _ a 623P4 mounting cord jack.

(2) Refer to Table A for dial connections.

is intended to be used with TOUCH-TONE

(2) Refer to Table B for dial connections.

with a 35Y3A TOUCH-TONE dial, install a

signaling purposes when battery and ground reversals

and modular jack using a D-180778

l-

Page 4

\

4 4 7 _ i,

TI TRANSMITTER

.

Fig. 3--Typical Installation, Desk Set Antique--Decorator Housing

ISS 4, SECTION 503-100-120

TABLE A

(1) Mount 623P4 jack and jack bracket to the

ROTARY DIAL AND network as shown in Fig. 5.

HANDSET CONNECTION

WIREOR LEAD COLOR CONNECT TO (2) Connect the four 623P4 jack leads and

rearrange network leads as shown in Table

BL F D.

6-Type BL RR

Dial W R

W GN (3) Thread one end of the D4BU mounting cord

into the set and plug into 623P4 jack as

R R shown in Fig. 5. For connections refer to Table

Handset BK B E or F.

Cord W GN

W R

TABLE B

TOUCH-TONE DIAL AND HANDSET CONNECTION

WIREORLEAD COLOR REMOVEFROM CONNECTTO

_

G -- F

BK -- RR

R-G -- R

35Y3A R -- T

Dial W -- GN

BL -- B

O-BK -- C

W-BL -- S

Line Switch R GN S

R -- T

Handset BK -- B

Cord W - s

w - R

3.09 Handset Cord (ordered separately). (4) Connect white leads to U3 receiver unit,

place unit in cavity and replace receiver

(1) Lay the set end of H4CJ handset cord on cap.

top of mounting cord and secure cord stay

to bracket on base as shown in Fig. 5. (5) Snap inside and outside connectors on T1

transmitter unit and terminate red and black

(2) Connect leads to appropriate network terminals handset leads (Fig. 3).

(Table A or B).

(3) Remove transmitter and receiver caps from _g_ The transmitter and receiver units,

cord leads through handset openings, feeding conducting surfaee. Transmitter and

customer-owned handset. Insert handset _ shah not be in contact with any

two white leads into receiver cavity and red reeeiver caps and transmitter and
and black leads into transmitter cavity, receiver elampinK surfaces in

Page 5

SECTION 503-100-120

840561810GUARDASSY contact with the transmitter or

receiver unit shall be made of
insulating material such as plastic

or rubber. Lacquer or paint shall

not be used to provide insulation.

D-180409 Kit of Parts, Optional (Desk Set Type)

$!_i_:ii!iii 3.10 When the shape of the customer's handset

_4 places the center of the T1 transmitter unit

.... separately) and install as follows.

.... grid 2-7/8 inches or further away from the speaker's

lips mount a D-180409 Kit of Parts (ordered

(1) Install the three 241B amplifier mounting

840169254 brackets at location shown in Fig. 7, using
BRACKET screws furnished with kit of parts.

840:560408 (2) Mount amplifier to brackets with screws

BRACKET furnished in kit of parts.

(3) Connect amplifier into telephone circuit in

Fig. 4--Installation Location of Components to Add accordance with Table G for rotary dial and

Polarity Guard Feature Table H for TOUCH-TONE dial.

TABLE C

POLARITY GUARD CONNECTIONS FOR TOUCH-TONE

TELEPHONE SET D-180461 GUARD ASSEMBLY

LEAD COLOR

DISCONNECT

FROM

NET. NET.

CONNECTTO

POLARITY

GUARD

Dial BK RR T

Line BR*
Switch W+
623P4 C S

Line Cord R:_
Jack Assy

..........

Polarity G RR
Guard W C

* If wired for bridged service or ring party.
+ If wired for tip party with no identification ground, 1A1 KTS,

or 1A2 KTS.

:_If wired for tip party with identification ground.

Page 6

ISS 4, SECTION 503-100-120

HANDSET CORD

MOUNTING

CORD

HANDSET

CORD STAY

.......

6234P JACK

Fig. 5mlnstallation of Mounting Cord Using D-180778 Kit of Parts

Assembly (CandIestick Type) 3.'12 Install 581A Telephone Set Base as

3.1 | Convert customer's candlestick housing

as follows. (1) Remove line switch from 581A base (current

(1) Remove four mounting screws which secures

baseplate to candlestick housing. (2) Remove square snap-in cover from bottom

(2) Remove dial bracket retaining screw from

elongated hole in baseplate. (3) Mount line switch to customer's set with

(3) Lift off dial mounting plate and remove

dummy dial by removing two screws. (4) A typical installation of a candlestick type

(4) See 3.13 for 6-type dial installation procedures.

(5) Remove dummy handset cord from base. ringer volume control to "LOUD" before

(6) See 3.15 for handset cord installation

procedures. _ When 581A base is mounted on a wall

Note: When disassembling transmitter housing proper operation o£ PIA ringer.
avoid grasping the horn. When reassembling,

make sure nut at pivot point is properly (6) See 3.14 for mounting cord installation
keyed, procedures.

follows.

model only).

of candlestick mounting base.

actuator toward terminal board.

telephone set is shown in Fig. 6.

(5) If 581A base (subset) is wall mounted, adjust

attaching subset to wall.

or other vertical surface, the base
should be flush against sur£aee £or

f&

Page 7

SECTION 503-100-120

H4CJ (1_

HANDSET CORD "l

\

/ X_

', )

-/

/

I
m

LEADS FURNISHED

WITH PARTS GROUP _ 581ATELEPHONE SET

u 840151054 (FIG. I ) // -._.._ BASE (LESS LINE SW)

I

"_.. MOUNT IN SUBSET

L _ /_/_,,, OR INSIDE WIRE ". L/. "

LINE SWITCH (REMOVED \ _ _ _ "',..L/_ / (SUPPLIED BY CUSTOMER)

FROM 581A BASE ) _......-I

\" "_._ __.._TE MINAL BOA D BY CUSTOMER)

\ _ DSBN MTG CORD

_ / "/_' COY ER (SU PPLI ED

Fig. 6--Typical Installation of Candlestick Type Telephone Set

840560408 3.13 Rotary Dial (ordered separately).

"<:_ ...... ::z::. AM IFIER (1) Install 6TA (chrome) or 6UA (gold) dial

z/ss_:_ii!::_._:_::_:,::::_::............... __ (Fig. 2) using three screws furnished with

" :.......................i ':'_:. ".... _j,_ (2) Conneet dial leads to terminal bloek furnishedwithcustomer's desk stand set as shown in

Fi .17.

__ 3.14 Mounting Cords (ordered separately).

(1) A standard D3BN mounting cord is required

for connections between the line wire,

840560390 terminals unless inside wire can be terminated

BRACKETS directly in wall mounted subset. A D6AA mounting

Fig. 7--Installation of D-180409 Kit of Parts stand set, except for party line service where a

connecting block and the 581A base network

cord must be used to provide the connections
between the 581A base and customer's desk

D10R mounting cord is used when tip party
identification is required.

Page 8

ISS4, SECTION503-100-120

(2) Install set end of D3BN and D6AA mounting 3.16 Line and Ringer Connections.

cords to 581A base, secure cord stay and

route cord as shown in Fig. 5. D6AA cord can (1) For all classes of service refer to Table E
lay on top of D3BN cord. or F.

(3) Terminate cord leads at network terminals. (2) The ringer volume control is blocked from

Wire connecting block end of D6AA mounting off position by a factory placed stopscrew.

cord to appropriate terminal block terminals To enable ringer cut-off feature, remove screw
furnished with customer's desk stand set (Fig. 17 through access hole in top of ringer gong. Advise
or 18). customer of cut-off position to avoid future service

3.15 Handset Cord (ordered separately).

(1) Install set end of H4CJ handset cord in of service, refer to Section 501-259-101.

opening located in base of customer's desk

stand set housing and secure cord stay to base. 3.17 Disconnection of Customer-Owned

(2) Connect two white leads to terminal block customer-owned telephone set housings should be

located on desk stand base (Fig. 17 or 18). disabled by the removal of all Bell System components.

(3) Remove transmitter and receiver caps from

customer-owned set. Insert handset end of

cord through opening in receiver handle and 4. MAINTENANCE
terminate two white leads to U3 receiver unit.

Insulate and store the red and black handset 4.01 Maintenance is limited to those components
cord leads at the terminal block and receiver installed as part of the telephone set base

unit (Fig. 17). group or listed in the Ordering Guide as replaceable

(4) Connect the red and black leads furnished and other customer-owned parts is the responsibility

with 840151054 parts group items 7 and 8, of the customer.

(Fig. 1) at terminal block in base of desk stand
set, extend leads toward transmitter unit.

(5) Snap inside and outside connectors onto T1 covering a particular item such as dials or

transmitter unit and terminate red and black ringers.

leads (Fig. 3).

calls.

(3) To permanently silence ringer for all classes

Telephone Set Housings: Disconnected

components. Maintenance of housing, handset,

4.02 Refer to appropriate section for maintenance

(6) Refer to Read, 3.09 for transmitter and 4.03 Refer to connection figures as an aid in

receiver unit insulation, locating and clearing trouble.

Page 9