Bell System 500A Reference

BELL SYSTEM PRACTICES
AT&TCo Standard
1. GENERAL
This section provides identification and
1.01
connection information for general purpose
500-type telephone sets.
1.02 This section is reissued to:
•
Include D4BT mounting cord
•
Revise Fig. 8 and Table F
Changes or additions in the body of tables are
indicated by shaded areas.
Code numbers such as 500C/D cover both
1.03
manual and dial versions, respectively, of
the same type telephone set to permit converting
to either type without changing the code number
stamped on the base.
the code number at one time to indicate the set
was equipped with a retractile handset cord.
2. IDENTIFICATION
2.01 The 500-, 501-, 554-, and 556-type telephone
sets are single line sets for use in common
battery areas, manual or dial.
501-type telephone sets are identical to a
2.02
similarly coded 500-type set except for the
addition of a 3-�lement, cold-cathode, gas-filled tube,
coded 426A.
554A/B, F, and 556A/B are standard, wall
2.03
mounted telephone sets.
same as the 554A/B except for the addition of a
426A tube.
The 554F is factory equipped with a 9-foot
2.04
handset cord.
The 554-type sets are suitable for
2.05
control with wiring modifications.
BSP 502-501-101-i03_1972-07-0l.;pg Scanned by Frank Harrell, (Cowboy Frank) Castle Rock, Colorado Jan 29,2012 23:39:08
500A/B, 500C/D, 500J/K, 501A/B, 501C/D, 501J/K, 554A/B,
554f, AND 556A/B TELEPHONE SETS
R
The letter
The 556A/B is the
@
American Telephone and Telegraph Company,
REFERENCE
2.06
Kit of Parts, respectively.
set for use with semipublic single slot coin telephone
set as an extension station.
2.07
and line switch are riveted to the base and are
not replaceable.
sets.
2.08
rubber grommets.
2.09
stop spring to provide a fifth position (OFF) on
was added to the ringer volume control.
2.10
D-180413 handset for impaired hearing, a G7AR
(MD) or G7B for weak speech, or a G8A (MD) or
G8B for noisy locations.
these handsets.
2.11
power induction.
Noise for additional information concerning inductive
interference.
2.12
connected
2.13
2.14
A
lead available in color include the dial or apparatus
blank, handset, mounting cord, and housing.
Printed in U.S.A.
SECTION 502-501-101,
500C or 554A manual telephone sets can be
ordered modified per D-180405 or D-180406
The kit modifies the
All parts of the set enclosed by the housing
mount on the metal base.
Table A list components of these
Ringers are mounted to base with two
P-43A456 washer head mounting screws in
Ringer off position can be provided, when
authorized locally, by bending back ringer
The G1- or G3-type handsets in these sets
may be replaced by a G6AR (MD), G6B, or
Refer
425A, 4-element tube may be substituted
for 426A, to care for cases of excessive
See section entitled Inductive
For negative stations in offices without
ANI, (R) lead from 426A tube may be
to
G if ringer operation is marginal.
Tube assembly is held to base of set with
single screw (Fig. 3).
These sets are available in all standard colors
as
indicated in Section 500-12(}100. Components
1972
Issue 3, July 1972
The network
to
section covering
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