Bell System Practices Plant Series Guide

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BELL SYSTEM PRACTICES
Plant Series
SECTION 502-150-901PT
Issue B, January, 1967
Pacific Tel.
DIAL-IN-HANDSET
F-56593 TELEPHONE HANDSET AND F-56594 TELEPHONE BASE
IDENTIFICATION, INSTALLATION, CONNECTION, AND MAINTENANCE
Contents
Page
1. GENERAL
1
2. DESCRIPTION . . . • • • . • . . • • • • • • • • • •• 1
F-56593 Telephone Handset .••••••••
F-56594 Telephone Base ......•.•..
3. INSTALLATION .•.••..•.....•••.••.
AC and DC Power Supply .•.••.••••
Single Installations .••••••••••••••••
Multiple Installations .••••••••••••.•
Lamp Circuit Modification .•••.•.•.•
1
3
3
7
7
8
8
4. MAINTENANCE . . . • • • • • • • •• • • • •• • . • 10
Transmission. • . • •. • •• • •• •• . • • •• • . • 10
Dial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Ringer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Dial Lamp and Recall Relay . • . • . . • 11
Cords . . . . •. •• • . . •. • . • . • • •. . • . . . • . • 11
5. CONNECTIONS • • •• • •• • • • •• ••• • •• • • 11
1. GENERAL
1.01 This s e ction covers the installation and
m a i nt e na n c e o f th e "TWO PIECE " Dial-
In-Ha n ds e t t ele p ho n e (Fi g. 1), which is simi-
lar to the F-56171 Dial-In-Handset.
1.02 It i s re i s sued to d e let e all r e fe r ences
to portable type installations. Since
this r e issu e co ver s a general revision,
marg in al a r r ow s ordina r ily us ed to indicat e
chang es ha ve b ee n omitted.
1.03 Th is hands et is des ig n ed prim a rily for
us e in hospitals and oth e r sim il ar in-
stit u tions. How ever , it may b e installed
e ls ewh ere.
Not e: Do not c onfuse th i s handset with
TRI M LIN E t e l e ph on e s et s .
1.04 The Dial-In-Handset is intended for
wa ll ins tallation only.
F-56593
....+ -a- - -- TELEPHONE
HANDSET
F-56594
m-- -- TELEPHONE
BASE
F-56594 Telephone Base With
F-56593 Telephone Handset
Fig. 1
2.
DESCRIPTION
F-56593 Telephone Handset
2.01 E lectrically, th e F - 565 93 Handset is a
comp le t e t e l ep ho n e ex ce pt fo r r i nger
and swit ch ho ok fu n ctions. It consists of th e
following compon e nts:
• LAI r ec eiv er unit.
• T 1 transmitter un i t.
© The Pacific T elep hone and T ele graph Company, 1 96 6
Printed in U.S.A.
Page l

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SECTION 502-150-901PT
• lOA dial.
• 53A lamp (illuminates dial, number plate,
and amber side light).
• 854A speech network mounted on a flex-
ible printed wiring card.
• F-56666 9-foot plug-ended retractile
handset cord.
2.02 Two molded shells, held together by two
screws, form the handset exterior. The
screws are concealed by the number card
holder and dial light-seal plate just below
the receiver heel. (See Fig. 2).
2.03 These handsets (and bases) are available
in white (-58). (See Table A.)
2.04 The lOA dial (Fig. 2) is a space-
saver design with a ''floating" finger
stop. A fingerwheel with a smaller diameter
than on other dials and with closer spacing
of finger holes is used. As a result of closer
spacing, the finger stop has to move. With
each pull of the dial it moves through an arc
of 52 degrees to a stop, then returns to its
normal position during rundown.
DIAL LIGHT
AMBER
SIDE LIGHT
P28E320
LIGHT SEAL
2.05 Letters and numerals on the dial number
plate and amber side lamp are illuminated
by edge lighting from a 53A lamp. Power for the
53A lamp is supplied by a 2012A transformer or
equivalent via line switch contacts in the tele -
phone base. Illuminated side lamp indicates t h e
handset is off-hook .
2.06 The number card holder (Fig. 2) accom-
modates Form E5002A number card. The
clear plastic retainer may be removed by using
a KS-16750, List 2 releaser or equivalent. An
aluminum plate (Fig. 2) under the number
card provides a light-seal for the 53A lamp.
2.07 The recall switch (Fig. 2), when de-
pressed, opens the tip and ring of the line
by operation of the Kl recall relay located in
the telephone base. Ope r at i on of the Kl relay
also opens the lamp circuit. This recall switch
is intended to release and regain a central office
line in plac e of operating the line switch. With
the recall relay operated, it is not necessary to
restore the telephone handset on the base switch
hook in order to call or be called.
Note: If recall switch is depressed durin g
conversation or dialing , central office equ i p-
ment may disconnect .
.•'
' ..
..
LOCATION
SCREWS
RECALL SWITCH
F-56593 Telephone Handset
Fig. 2
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2.08 The 854A network {Fig. 3) used in the
F-56593 handset provides transmission
characteristics similar to a 500 - type set,
The network includes a jack for plugging in
a five conductor handset cord, a recall switch,
and a lamp socket for a 53A lamp.
TRANSMITTER
CUP
TIP PARTY
I DENT. SW I TCH
854A Network (Flex-Strip)
Fi g. 3
2.09 An F-566 66 pl ug -e n de d retra ct il e hand-
se t co rd { Figs . 1 a nd 1 4) con n e c t s the
h a nd s e t to the te l ep hon e b ase . T his co rd i s
p
lu g - e nd e d for c onn ec ti n g to the h a nd se t,
an d is sp a d e- tip e nd ed f o r ba se co nn ec ti on s .
(Co rd is pa c k aged wi th each F -5 6593 h a n ds e t.)
Iss. B, SECTION 502-150-901PT
2.10 The handset cord {F-56666) is a five con-
ductor cord. The fiv e conductors are re-
quired for full party, lamp, and recall relay
operation.
F-56594 Telephone Base
2.11 The F-56594 telephone base (!Fig. 4)
is wired for individual line service .
Wiring changes are necessary for other serv-
ices. (See appropriate Tables and Figs.)
2.12 The telephone base ha s a metal base on
which are mounted:
• A card operated line swi t ch {switch hook).
• PlA ringer with a 165A mounting adapter.
• Kl recall relay.
• Terminal board.
• A plastic housing {shell).
2.13 Two captive screws for fastening the
plastic housing to the base are located
beneath the P-82E858 BELL SYSTEM identifi-
cation plate {Fig. 4). Use a kS-16750, List
2 releaser, or equivalent, for removal of plate.
2.14 The PIA ringer has a v olume c ontrol oper-
ated by a l eve r extending from the ri g ht
side of the base mounting. {See Fig. 6.) A
ringer cutoff is made a v ailable by the remo v al
of a stop s c r e w t hrough an ope n ing in the gong.
{See Fig. 5.)
2.15 Figs. 4, 5, and 6 show th e PlA ringer
with adapter . The figures also show the
lo c a t ion of th e stop screw and the bias spring.
PlA ringers have 5 leads. The (BL) lead is used
for part of the tip party identification circuit
{r e f er to approp r iat e parts on conn ec tions). The
(S) and (SR) leads are insulated and stored .
2
.1 6 Mountin g cords are av ailabl e for this base
in three len g ths only . {See Table A.)
Thes e cords may be u sed in lieu of inside
wire as r e qu i r e d.
2.17 Wh en conn ec tin g for 4- pa rty full selec t iv e
or 8-party semis e le cti v e ringing , a 426N
diod e may be in s ta lled in th e base. Plac e the
diod e in th e op e ni ng pr ovi de d in th e t erminal
board. (See Fi g. 6.) Con nect t he lead s as
shown in th e a ppropri a t e conn e ction s ec tion.
3. INSTALLATION
3 .01 Th e hand s e t (F - 5659 3) a nd ba s e {F-5659 4)
ar e pack ag e d se p a r a t el y. To r e ceiv e a
c
ompl e te Dial-In- Ha nd s e t tele pho ne s e t, on e e a ch
m u
st be ordered , suffi x ed wit h -58. Fo r ex a m p l e :
• l Bas e , T el ep ho ne , F -5659 4-5 8
• l S
et , T el eph on e , Ha nd, F - 56 59 3-58 (A 9-
fo ot r etra ctil e h a nd se t c ord i s in cl ud e d.)
Note: Mo un tin g c ord s are not in cluded wit h
e ith e r th e h an dse t or b ase . Th ey mu st b e o r -
de r e d s e
para te ly a s r eq ui r e d. (S ee Ta bl e A ,)
P age 3

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SECTION 502-150-901PT
Pa ge 4
HOUSING SCREWS
P82E858
IDENTI Fl CATION
PLATE
LINE SWITCH
PLUNGER
F-56594 Base
Fig. 4
LINE SWITCH
ARM
• • --- Kl RECALL
RELAY
;a,.,.,.- ~~~ TERMINAL
BOARD
OPENING FOR
RINGER BIAS
ADJ.
OPENING FOR
STOP SCREW
MTG. CORD
OR IW
HIGH TENSION BIAS 63A
P-27E070
STOP SCREW RESONATOR
NOTCH SPRING GONG
(REMOVED) I
ADAPTER
PlA Rin g er With Adapter
F ig . 5

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LEAD NO. 1
STOP SCREW
426N
DIODE
Iss. B, SECTION 502-150-901PT
LEAD NO. 2
426N Diode Installation (See Table D)
Fig. 6
3 .02 When placing the instrument, cons id er
the following:
• Safety for yourself, customer, and main-
tenance personnel.
• Availability of AC power outlet for 2012A
or equivalent transformer.
• Location of telephone base so ringer
volume is adequate for area.
• General appearanc e of installation.
3 .03 Selection of location and method of in-
stalling sha ll be consistent with existing
standard practices. {S ee Figs . 7 and 8.)
3.04 The telephone handset {F-56593 ) is
shipped from the factory with the tip
party identification screw in an open position .
{See Fig. 2. )
3.05 Wh en tip party identification is required,
the screw-type switch shall be tightened
firmly . When no lon ger required, the screw
shall be backed off until tension is felt (ap-
proximately 1-1/2 turns). (See Figs. 2, 17
and Table C.)
3.06 When required, the 155A adapter and/or
182B backboard shall be used to mount
the telephone base.
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SECTION 502-150-901PT
Page 6
INSIDE WIR-E TO TRANSFORMER
Typical Wall Installation
Fig. 7
20 12A TRAN S FORMER
2A CLAM P
Transformer Installation
Fig. 8

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3. 07 A l 55A adapter plate may be used
to wall-mount these bases over a con-
duit outlet box or 63-type bracket. The let-
ters TOP stamped near one end of the plate
indicates the proper positioning. After plate
is fastened, secure base (housing removed)
with two machine screws furnished with the
adapter. (See Fig. 9.)
3.08 A 182B backboard may be used to wall-
mount the base. This backboard is
available in white to match the telephone base.
3.09 When base wiring is exposed, terminate
line and transformer wiring at a common
bridging point, such as a 42A or 1044 type
connecting block. Run one quad and one
paired or equivalent (5 conductors) from
connecting block to the base. Wiring may
enter the base from openings at the bottom,
top, or through the backplate.
Note: Five (5) conductors are al-
ways required wh e n this Dial-In-
Handset is installed on two or more
party services. AT NO TIME SHALL
THE STATION PROTECTOR OR
SIGNALLING GROUND BE BRIDGED
TO THE AC TRANSFORMER
GROUND.
3.10 In cases where an inside wire is already
in place through a wall, an exposed wire
run may be necessary between the telephone
base and the transformer. If a l 55A adapter
plate is used, the exposed wire may enter the
base through openings at top or bottom. If a
l
82B backboard is us ed , th e ex posed wire may
enter the base through the backplate from be-
hind the backboard.
AC and DC Power Supply
3.11 Power for the 53A lamp and Kl recall
rel ay is furnished from the same 10- or
18-volt AC power transformer. This AC
voltage is rectified to DC (11 to 20 volts) in
the F-56594 base.
3.12 The 53A lamp is a 10-volt AC lamp.
while th e K l reca ll rela y r e quir es 11
to 24 volts DC for proper operation. The
minimum DC voltag e for oper at ion of the Kl
relay is 11 volts. The DC voltage must be
m easu r ed across the KS-16390, List 6 ca paci-
tor. It is loc a ted in the telephon e bas e on
th e l eft side be low the t ermina l board.
3.13 Th e c orr ect pow e r supply (AC) is gov-
erne d by the t yp e of installation in-
volved. As follows:
Single Installations
3.14 Where a single Dial-In-Handset is in-
volved, us e a 2012A transformer. Select
Iss. B, SECTION 502-150-901PT
TEL. SET
MTG. SCREW
I55A
155A Adapter Typical Installation
Fig. 9
a 105- to 120-volt AC receptacle that is not
on a circuit controlled by a switch. A 2A
clamp (Fig. 8) is availabl e to secur e the
transformer to the AC outlet.
3.15 For proper illumination of one dial and
the operation of one Kl relay, the length
of wire between the transformer and tele -
phone base (F-56594) should not exceed 250
feet. (In the event a 2012A is inadequate, use
a 2075A transformer and follow install a tion
inst ruct ions co ntain ed in 3 .17 through 3 .23.)
Not e: Use a 2012A transformer,
not a 2012B. The pow er output of
th e 2012B is not adequate for
simultaneous operation of the l amp
and Kl r ecal l relay. (Maximum
current drain occurs at this time.)
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SECTION 502-150-901PT
3.16 Do not use a 25-foot mounting cord on
any Dial-In-Handset installation be-
cause of the added resistance to the lamp
and relay circuit.
Multiple Installation
3.1 7 DO NOT use any power plant furnishing
power to a KTS, although the 18-volt
AC tap or punching is vacant. A SEPARATE
power supply is required to operate these
handsets.
3.18 When 2 to 10 of these handset tele-
phones are required, a 2075A, 15-to 18-
volt AC transformer or equivalent, must be
used.
3.19 Keyhole slots are provided at the rear
of the 2075A transformer for easy in-
stallation. Use a suitable backboard when
mounting on surfaces requiring backboards.
The proper AC plug adapter and retainer
must be installed at all times.
Note: Additional 2075A transformers shall
be added as required, providing there are ·
e
nough AC receptacl e s availabl e . Oth e rwise
follow instructions contained in 3.20. (DO
NOT USE 393 TYPE TRANSFORMERS.)
3.20 When an installation requires 11 or
more of these handsets, refer to ap-
propriate section on power plants for s el e c -
tion. Select a power plant furnishing 15 to
20 volts AC at 1.4 to 3.0 amps.
3.21 A ma xi mum of 35 handsets can be
operated properly from one 18-volt AC
2.0 amp fuse or tap. This single pow e r sup -
ply must be fused again (201 D KTU) in groups
of five. Each group must be protected by a
.5 amp fuse (24-E).
3 .22 Th e l e ng th of th e individual fe e d er pairs
from the power sou r ce to the telephon e
base shall not exceed 19 ohtns.
Lamp Circuit Modification
3.23 Wh en an 18 volt AC transform e r or
power plant supply i s used, modify the
5 3A lamp circuit only. This required · modifi-
cation is don e in the F-56594 bas e. The
modific a ti on will lower th e AC v olt a ge to
ac c omtnodat e t he 53A lamp . To modify the
53A l amp circuit :
•
Move the (BK) lamp lead on punching
7 to spare (G) punching.
• Conn e ct a 124 ohm .5 watt resistor
(No . 227 A ). or equ i va le nt . be tw ee n pun ch -
ings (7) and (G).
Page 8
•
In the event the (G) punching is being
used for party identification and ringer
connections, use a D-161488 connector to
bridge the resistor and {BK) lamp leads.
• Dress resistor wiring in such a manne r
that they will not contact other punch-
ings of the terminal board.
3.24 To separate housing frotn base (F-5 65 9 4)
and shells of (F-565 9 3) telephone h and-
set, proceed as follows:
(a) Base (F-56594), (See Fig. 10.)
( l) Retnove housing:
• Retnove co v er pl ate (BELL SYSTEM
identification plate) below switch hook
with a KS-16750, List 2 releaser.
• Loosen the tw o capti ve screws w hic h
are now exposed.
• Lift housin g off.
(2) R e plac e housin g:
•
Hold the housing ups i de down so that
li n e switch plunger i s exposed.
• Plac e finger on front of the exposed
plunger to hold it in place .
•
While holding plunger, turn h ousing up-
r i g ht and plac e in pos i tion ov er the
backplate.
• Th e plunger tnay no w be rel eas e d as it
will not rest on th e lin e switch arm .
• T i
ghten housing screws and replace
co ve r plat e by ins e rting one e nd of it
in rece s s. Put lig ht pr e ssure on th e
other end to cause a slight outward
bow and snap into recess.
(b) Telephone handset (F- 5659 3). (See
Fig. 2.)
(
l) Remove deck and shell:
• Retno v e number pla te card r e tained
w ith a KS-16750, List 2 rel e aser.
• R e tnov e nutnb er card and l ig ht shield.
• Loosen two captive screws which are
no w e xpos e d. (53A lamp and tip iden-
ti fi cation s crew a re a lso e xpos e d.)
Not e: Do not tight en or loos en capt i ve
screws wh ile holding handset. Place it
on flat smooth surfac e while working
w it h th e c apti ve scre ws.

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• Lift deck and shell off. Exercise caution
not to damage shell area around handset
cord jack or plug retainer guide.
(2) Replace deck and shell:
• Engage deck and shell at the handset
cord and jack opening first.
• Align the two captive screws in decking
so they will line up with their threaded
anchors inside the shell.
• Gently engage remaining surfaces of
shell and deck.
• Fasten captive screws and replace light
seal, number card, and card retainer.
F-56594
,,,..-/TELEPHONE
BASE
Removing Identification Plate
Fig. 10
3.25 A 426 diode (Fig. 6) must be installed in
the base mounting when connecting for 4-
party full selective or 8-party semi-selective
ringing. Place the diode in the opening provided
in the terminal board and dress leads to termi-
nals and D-161488 connector. (See Table D.)
3.26 If an extension ringer is required, use a
687B subscriber set or equivalent. Refer
to connection information in this section (Fig.
15) and appropriate sections covering subscriber
sets and polarized ringing.
3.27 Wh en extreme noise inductions exist (a
condition which usually requir es the use of
a 3 - e lement tub e connected without the control
gap across the line), use a 74A connecting block
rather than the 426N diode. The 74A connecting
block (Fig. 11) contains a 425 tube (4-element)
and a terminal strip. Five conductors are re-
quired between connectin g block and base
mounting. Refer to Fig. 16 for connections.
Iss. B, SECTION 502-150-901PT
TO TRANSFORMER
•
425A TUBE
74A Connecting Block - Cover Removed
Fig. 11
3.28 The biasing spring in the PlA ringer is
set in the high tension n otc h at the
factory . Use long-nose pliers or a b e nt paper
clip to lift the bias spring and move it to the
right of the notch (Fig. 12) through opening
in terminal board.
,.
BENT PAPER
CLIP
Adjusting Bias Spring in PlA Ringer
Fig. 12
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SECTION 502-150-901PT
3.29 The bias spring tension is the only ad-
justment that can be made to the PIA
ringer.
3.30 For ringer cutoff, remove stop screw
and move volume control to extreme
LEFT position. (Fig. 5.)
Note: If stop screw is to be put back in
place, set volume control to LOUD position
to avoid breaking volume control cam.
4. MAINTENANCE
4.01 Maintenance of this handset is limited
to the following (Table A and B) com-
ponent parts of the telephone handset and
base:
HANDSET
CORD
TABLE A
CORDS
MOUNTING
CORD CORD LENGTH
F-55604-58
5-1 /2 Foot
"~ F-56666-58
F-55731-58
F-55732-58
~ 'Available in 9- foot length only.
TABLE B
REPLACEABLE PARTS
9 Foot
13 Foot
F-56593 HANDSET
F-56594 BASE
lOA Dial
PlA Ringer
Tl Transm i tter Unit
B - 696796-58 Housing
LAI Receiver Unit
P-82E858 Cover Plate
53A Lamo
P-25E803 Retainer
P-28E320 Light Seal
P-88E658 Dial Blank
Transmission
4.02 If transmission trouble is in the hand-
set, check the following:
• Worn, open, or noisy cord .
•
Defective transmitter or receiver unit.
• Dirty rec a ll swit ch contacts.
• Loos e conn e ctions.
• Defective 854A network, flex circuit, or
components. (See Fig. 3.)
• Dirty or worn dial contacts.
Page 10
• Transformer or power supply .
•
74A Connecting block.
4.03 If transmission trouble is in the 854A
network, replace the handset.
Dial
4.04 Parts replacement is limited to finger-
wheel and finger stop. Refer to section
on 1 OA Dials.
4.05 To replace a defective lOA dial, it is
necessary to:
• Remove number card and light-seal
plate.
• Loosen two mounting screws.
• Separate the sh e lls.
• Disconnect the network flex-strip con-
nections at the receiver cup.
• Remove mounting screw holding dial
light block.
• Disconnect flex-strip connections at 1 OA
dial.
• Lay flex-strip back. DO NOT FOLD
FLEX STRIP.
• Remove three dial mounting screws;
then remove dial.
• Connect the two flex-strip connections
to replacement dial before fastening
di al to shell.
• Follow above steps in reverse order to
r e a s semble.
Ringer
4 . 06 To replace a defective PlA ringer:
• Disconnect ringer leads.
• Remove terminal board mounting screws.
• Raise e nd . of te rminal board.
• Remove ringer mounting adapter from
bas e.
• Remove mounting adapter from ringer.
• Fasten mounting adapt e r to new ring e r.
• En ga ge rin ge r v ol um e control with ad -
justin g lever before fastening rin ge r
mounting adapter to base.

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(h) Reposition and fasten terminal board.
Dial Lamp and Recall Relay
4.07 If lamp and/or Kl recall relay fails to
operate correctly, check for the follow-
ing:
• Open lamp (Fig. 13).
• Defective or unplugged transformer or
power supply.
• Commercial power failure or power
turned off.
• Loose connections.
• Dirty or improperly adjusted switch hook
contacts.
• DC voltage to Kl relay is less than 11
volts. (Measure this voltage across the
KS-16390, List 6 capacitor only.)
• 124 ohm resistor; it may be defective
or installed incorrectly in the circuit.
(See 3.23.)
4.08 If illumination is poor and the recall
relay fails to operate at times, check
that the length of inside wire does not exceed
250 feet or 19 ohms.
Iss. B, SECTION 502-150-901PT
Cords
4.09 To replace the plug-ended handset cord:
• Use a KS-16750, List 2 releaser or
equivalent.
• Insert tool in space provided.
• Apply pressure against spring clip
toward body of plug. (See Fig. 14.)
• Pull plug out of jack when spring clip
has been compressed.
4.10 Five conductor mounting cords from
Table A (or equivalent) are required.
(DO NOT INSTALL A 25-FOOT CORD.)
5. CONNECTIONS
5.01 The following (Figs. 15, 16 , and 17
and Tables C and D) furnish additional
r e quired wiring changes for the type of
service and equipment involved.
5.02 If this instrument is used as a key
telephone extension, a 213B K-T-U-
must be used. Use appropriate practice for
terminal designations. Connect T and R leads
so "L
11
relay operates on station short. This
method remove:; need for "A
11
and "Al
11
leads.
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SECTION 502-150-901PT
Page 12
Replacing Dial Light
Fig. 13
PRESSURE
APPLIED
Removing Cord from Handset Assembly
Fig. 14

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Iss. B, SECTION 502-150-901PT
LINE
:·::'.: .
6878 SUBSET
HANDSET RINGER
~s(~~~.....,.. = ffii~:: : ~~~~~~~~~~----
GRO
- RING
PARTY
(-t TIP
p
PARTY
LI
687B Subscriber Set, Connections
Fig . 15
i
i
TO
EXTENSION
RINGER
STATION
TO
EXTENSION
RINGER
STATIOlll
Pag e 13

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SECTION 502-150-901PT
INSIDE WIRE ·•· ·.
74A CONNECTING BLOCK
WITH 425A TUBE
(NOTE 1 AND 4)
· ~ PIA RINGER , MOUNTING CORD ANO/OR
Ii< INSIDE WIRE CONNECTIONS AT TERMINAL BOARD
IYl
~ IN TELEPHONE BASES
~~
ffi (NOTE 3)
I~
~*
(Y)
(Y)
**
PA~n [ :::::~ ;
GRO
(R)
(R)
4
(G)
(G)
** •
L2
+ [ ( +)RING
PARTY
t 1+1 TIP
GRO
I
0
03
(Y)
4
(BK)
2
(W) (R) (BK)
(BIO (BK)
K
B
(Y) (Y) **
(R) (R)
L2
(BK)
(GI (G)
LI
G
I •
0
3
0
TL!i~~ [:~~~~~~ : _, i! _,, i ,_ :_· ... , ·: ~ _, :_ ,, i ' . :.; _. ' ~~~~~~=:)->=~:~~~*~--*-_-_- _ -_-_-_-.:..::::::):(:R:.:K~)~~~ ~ . iii\ @ ;- • _-_-_-_-_-:_-_-_-_.
l ~
Page 14
I l -MOUNTING CORO CONDUCTORS.
[)-INSIDE WIRE CONDUCTORS.
* -INSULATED ANO STORED.
t -FOR TIP STATION-REVERSE
RI NG ANO T I P LEADS AT
CONNECTING BLOCK.
** -USE BRIDGING CONNECTORS
OR EQUIVALENT.
I
I
A
B
NOTES:
1. FIVE CONDUCTORS REQUIRED
BETWEEN 74A CONNECTING
BLOCK AND TELEPHONE BASE.
K
2. TWO INSIDE WIRES ARE REQUIRED:
ONE QUAD AND ONE PAIRED OR
TWO TRIPLES.
3. DISCONNECT ( S) L INE SWITCH LEAD
FROM A OF TERMINAL BOARD,
INSULATE ANO STORE.
4. MAY BE LOCATED AT OUT-OF-THE
WAY LOCATION BETWEEN PROTECTOR
ANO BASE.
74A Connecting Block and Ringer Connections
For Extreme Inductance Interfer e nce
Fig. 16
(RI
IS-RI
16500
($)
5000
18LI
5000
(8Kl
(RI
IS-RI
16500
ISi
5000
(8Ll
5000
IBKI

TCI Library https://www.telephonecollectors.info/
F5659"f
BRSE
Lll\IE - TERM
tv1J?E5 LJtJA/?f)
OR
A'//VGCA' -
/>IA
,;;;WE
SJ-i '/. -.-C/I
PR /NTE.O
1-'W;?, /;VG 80A/?L> AS'o~M.8L Y
MT<>
CORD
1ovl Y
AC l 811'
C3
100 MF
5
,...,. (R )
"""' (!'\'·SR)
~ '-i~~(..:..:....G~ ) ~~--+-+-~~~~--+-.i--~-
C0 ·'I)
~ C O-R)
Kl
-
I
,....,
<_.;
A
-
,.
7
n
+ 'U...,_
- ~ B
:;- ?">
--........._
(W·BR)
(BL:W)
( S-W )
ESIM.
'
~
I W -Sl
L-i--o
~
I
I t
E8M3
I
0 I
..
~EBM2
~
0 I
I
:EBM I
~
I
-
~
-
'--
p;iT.o;
CR4
..._,
... ,
478A
}
!'Ill ~- ~ }10
1
?1?..t'
'(!()A /OOA IOO A
....
r•
Cl?.3, ~A ,p9 <w-s)
~~-+-t- -~ ~~~ -+++ ~~~C -R~-5--.~ - ~v
, BK' ~. I 1,., (s-w)
'--~~++-+~;..:_;,,;~-+-+-~~~~~-H~~-,t;-~- . -
1
~ 4lM_~~-tf
(~ .3,
~-3~
''
, ,
CG) ,, 4,...
,,4_
' ' I , '
()')..,,:~
7
~~
e
Iss. B, SECTION 502-150-901PT
,C5"6 3"93
r------------------- 1'/A/'rZ>S ET ASSY.---------
RI NG
TIP
'>
s
~
(NOTE!)
1~
b
-
....__
,r-
~
/
,...
>-
i- n,
X-•
t
_._..
T
NO TES:
1. For Ti p Party Ident if ying Ground {1000A or 2650 A Cen tr al
Office) tight en screw sw i tch loc at ed under number card.
2. Ground ma y be omi tt ed if not required for Service; not r e-
quir ed for pro te ct ion of di al lig ht tr ansfo rm er .
3.
To permanently silence ringer: Remove { R) Ringer lea d from
K on Terminal
Boa rd. Ins ulate and store. For Tip Party ! de nt.
{
BK) Rin ge r l ead must be on B of T erminal Board.
4.
Termi nat ed on bridging connec to r with {Y) Ti p !d ent. lead
when 74A connect ing block is used.
• Insu
lat ed and stored
TABJ,,E C
LI NE AND RI NGE R CONNECT IONS
Wi re Or Ind. Or
Ri ng T
ip Party
Lead Bridged Party No !dent. 1000 Or 2650
Ground Ohm
Ins id e R L2 L2 Ll
Ll
Wire At G Ll Ll L2 L2
Mt g. y 1 1 1 1
Bas e
BK
3 3 3 3
Ri nger R K K K K
Leads
BK Ll
G G G
No te 3 & 4
BL
B ..
B ..
B'·
B'·
F-56594 Base and F-56593 Handset Connections
Fig. 17
Page 15

TCI Library https://www.telephonecollectors.info/
TABLE D
CONNECTIONS
FOR 4-PARTY FULL SELECTIVE OR 8-PARTY SEMISELECTIVE RINGING
Line Wire Dial
Lt
Mounting Cord
Party Connections at Trans Leads at
Conn Block Connecting Block
(Note 1) R G y 1 3 R G y w
BK
l<Note 2)
-RING R G y y B R G y y B
(1) (2)
(3)
(4)
(5)
-
TIP R G y y B G R y y B
(2)
(1)
(3) (4) (5)
+RING R G y y B R G y y B
(1)
(2)
(3) (4) (5)
+
TIP
R G y y B G R y y B
(2)
(1)
(3) (3) (5)
Note 1: Disconnect (S) line switch lead from punching A of terminal board, insulate and store.
2: Do not connect station ground or AC transformer ground together at an y time .
* Connection in base (F-56594).
** Removal of these leads clears punching (B) for diode termination.
t Must be installed in this position <::p___.1 @
( ) Punchings on 1044A Connecting Block. r--
Mounting Cord or Inside
426N
Wire at Ter minal Block Di
ode t
R G y w
BK
CD
@
L2
Ll
3
G 1 L2 B
L2*
Ll*
3*
L2 Ll 3
G 1
L2 B
Ll* L2* 3*
L2
Ll
3
G 1 G B
L2* Ll* 3*
L2 Ll
3
G 1 G B
Ll* L2* 3*
BK
K
K
K
K
Iss. B, SECTION 502-150-901PT
Ringer Leads
R S
'BL
S-R
**
3 G
"O
Cl)
I'<
0
3
....,
G Cll
"O
§
"O
Cl)
L2
....,
G
c1$
......
;:l
Cll
.s
L2
G
S tr ap Tip
fro m
A
BK
G
G
L2
L2
I de nt
Le
ad
Y* *
"O
Cl)
I'<
0
....,
Cll
"O
§
Cl)
....,
c1$
......
;:l
Cll
.s
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16
Pa g es