Bell System Practices TOUCH-A-MATIC 2872A 1M User manual

BEU
SYSTEM
PRACTICES
AT
&
TCo
Standard
SECTION
503-603-1
01
Issue 4,
May
1978
2872A
1M
OR
2872A2M
TELEPHONE
SET
(TOUCH-A-MATIC® AUTOMATIC
DIALER)
CONTENTS
PAGE
1.
GENERAL
2
2.
IDENTIFICATION
3
Design
Features
3
Optional
Features
3
Ordering
Guide
4
Operating
Features
6
3.
INSTALLATION
6
STANDARD
INSTALLATION
6
Installation Check Procedure
7
OPTIONAL
APPARATUS
INSTALLATION
9
D-180492
Kit
of
Parts
(W
i
th
Speakerphone)
D-180493
Kit
of
Parts
(Dial
Tone
Detector
and
One-Touch Colling
Sw
itch)
D-180494
Kit
of
Parts
(2
/ 4-Wi
re
9
9
Service)
10
D-180818
Kit
of
Parts (Record Disable
and
Dial Intermix
Features
)
10
Si
ngle
Une Service
12
Head
Telephone
Set
12
COMPONENT LOCATION AND ACCESS
INFORMATION 12
Location
Of
Components
12
CONTENTS
PAGE
Mounting
Cord 13
Network
Terminals
16
Power
Supply
(PSB)
Terminals
16
Une Key Removal
17
Faceplate
Removal
17
Handset
Cradle
Removal
17
Housing Removal
17
4.
CONNECTIONS
18
5. OPERATION 18
Record A
Number
Into Memory 18
Change
A
Number
In
Memory
19
Delete A
Number
From Memory
19
Automatically
Dial A
Number
From
Memory 19
LAST
NUMBER
DIALED
Feature
19
End-to-End Signaling
20
6.
MAINTENANCE
20
Trouble Analysis
20
20
Memory
21
Dial 21
6-Button Une Key 21
NOTICE
Not for use or disc
lo
sure
ou
tside the
Bell
System except under written agreement
Pr
inted in U.S.A.
Page
1

SECTION
503-603
-1
01
CONTENTS
PAGE
Ringer
22
Buzzer
22
Handset
Jack
22
Hand
set
22
Facepla
te
23
Speakerphone
23
1.
GENERAL
1.01
This section contains identification, installation,
connectio
n$,
operation,
and
maintenance
information on
the
2872A1M
(
MD
)
or
2872A2M
te
lephone set (TOUCH-A-MATIC service) (Fig. 1).
1.02
This section is reissued
to:
• Show
2872A1M
telephone set (MD)
• Revise Fig. 1 through
5,
7
th
rough 12, and
14
• Revise Tables A through
G,
J, and N
• Add Fig.
13
• Show
2872A1
faceplate
MD
• Add Tables K, L, a
nd
M
• Eliminate connection information for
82A
connecting block
• Add
D-18
0818
Ki
t of
Parts
(Re
cord Disable
and Dial [ntermix Features
• Add reference for use
of
stati
on head
telephone adapters.
Since this reissue covers a general revision, arrows
ordinarily used to indicate changes have been
omitted.
Fig
. 1- 2872A1M (
MD
) or 282A2M Telep
hone
Set
Page
2

1.03
The
2872A1M
or
2872A2M
telephone set is
factory-wired for use with
lAl,
1A2,
or
6A
key
telephone systems (KTS). They may
be
converted (Table
J)
for use with
lA
KTS
.
1.04
The telephone sets are available in the
following colors:
• Black (
-03)
• Green (-51)
• White (-58)
• Lt. Beige (
-60).
1.05
The 2872Al
(MD)
faceplate is available in
only the satin-silver (
-87)
color.
1.06
The 2872Bl decorative faceplates are available
in the following colors:
• Teak Woodgrain
(-108)
• Walnut Woodgrain
(-109)
• Matte Aluminum
(-122)
.
2.
IDENTIFICATION
2.
01
The
2872A1M
or
2872A2M
telephone
set
provides all
standard
features of a 6-button
key
telephone set plus (manual) TOUCH-TONE
"'
dialing, automatic dialing of
31
frequently called
numbers, and a LAST NUMBER DIALED
scratch
pad
memory.
2.02
The
2872A2M
telephone set differs from
the
2872A1M
set only in the battery circuit.
The
2872A2M
set has a battery interlock circuit
that
prevents the set from dialing automatically if
the battery is not plugged in. Also, the
2872A2M
telephone
set
utilizes a newly coded
battery
(KS-20390lA) which can not
be
used in the
2872A1M
set.
2.03
Design
Features:
• Modular key telephone
set
• Integrated circuit
RC
TOUCH-
TONE
oscillator
• Integrated circuit memory
ISS
4,
SECTION
503-603-101
• Surge protector
• Polarity guard (removable for dry circuit
application)
• Common audible ringing
• Buzzer
•
Bu
sy lamp diode
• Line pickup buttons convertible to nonlocking
signal buttons
• Memory
buttons
from which to select
preprogrammed
telephone
numbers
for
automatic dialing
• Capability to record and automatically dial
31
telephone numbers of up to
15
digits
each
• Last number manually dialed memory
• Plug-in battery
• Capability to pause for subsequent dial
tones during automatic dialing (WAIT input)
• End-to-end signaling for
data
application.
2.
04
Optional
Features
(Refer
to
Table
A):
•
Speakerphone-either
3B
or
4A
speakerphone
systems may
be
added to stations
• Dial Tone
Detector-automatically
starts
dialer when precise TOUCH-TONE dial tone
(350
Hz and
440
Hz) is present.
• One-Touch Calling, (requires both dial tone
detector and speakerphone)
-depressing
one
memory button will automatically
turn
on
speakerphone, detect dial tone, and dial
complete number.
Note:
All dial tones encountered in the
process of placing a call must
be
precise
TOUCH-TONE dial tone if the call
is
to
be
completed automatically.
• Record Disable-
turns
off
the
recording
feature to prevent accidental erasures of
previously stored numbers
Page 3

SECTION
503-603-101
Booklet, Instruction, Subscriber,
SIB-2455B
(d)
Optional
Apparatus
(order
as
required):
• Kit of Parts,
D-180492
(must
be
used for
speakerphone service)
• Kit of Parts,
D-180493
(Dial Tone Detector
and One-Touch Calling switch)
• Kit of Parts,
D-180494
(for conversion to
4-wire service)
• Kit of Parts,
D-180818
(Record Disable and
Dial Intermix)
Note: This kit of parts may
be
used only
with sets equipped with a
2870B
memory
• Faceplate,
2872B1-*
Note:
If
set is equipped with
2872A1-87
faceplate, then an upper housing
(870A1U-*)
of the appropriate color must also be ordered.
• Set, Head Telephone [using Plantronics Jackset
Model
JS180-1
(2
foot cord) or JS180-02
(7
foot cord)).
•
Add
appropriate color suffix
(1.04
or
1.06).
2.07
Operating
Features
(Fig. 2).
• Dial (TOUCH-TONE dial).
• Line
key
(635BT5),
6-button
key.
Hold with
five line pickup buttons which are convertible
to nonlocking.
An
additional momentary
contact (logic reset switch) is attached to
the Hold side of the
key
to reset the logic
circuit anytime a
key
button is depressed.
• 32-button array of
lo:;v
force,
low
travel
nonlocking memory buttbns arranged in three
columns. Left and right cblumns have eleven
buttons, center column has ten buttons.
•
LAST
NUMBER
DIALED button located in
lower right corner of memory array, when
momentarily depressed, automatically redials
the last number manually dialed.
•
RECORD
button
(nonlocking),
when
momentarily
depressed, lights the
RECORD
lamp and
Page 6
enables the memory circuits to store telephone
numbers.
•
RECORD
OFF button (nonlocking), when
momentarily depressed extinguishes
the
RECORD
lamp, indicating
that
the dialer is
switched out of the record
mode
.
•
WAIT
button (nonlocking),
when
momentarily
depressed during recording operation, enters
a
code
into memory to initiate a halt in
the automatic dialing sequence (used where
access digit(s) required].
3.
INSTAUATION
STANDARD
INSTAUA
TION
3.
01
Make
all wiring changes and telephone set
modifications (Table
A)
before external
connections are made
to
the set
(4.01).
Caution: Do
not
plug
in
eitber
battery
or
power
unit
until
all
connections
and
modifications
are
completed.
Take
extreme
care
not
to
damage
tbe
exposed
components,
circuit, etc.
wben
tbe
set
is
opened.
3.02
The set is shipped from the factory with
the battery disconnected. After all wiring
changes and modifications have been completed,
connect the battery (Fig.
6)
by tilting the set
up,
and inserting the battery plug into the mating jack.
Note: Write date of installation
on
label
provided
on
battery.
3.03
Install the 95B-type power unit within
150
feet
(24
gauge conductors) of the telephone
set and plug into an ac outlet not controlled
by
a
switch (continuous ac power is required). Aretaining
clamp
(841050818)
will
be
shipped with the 95B-type
power unit and should
be
mounted to the ac
receptacle to hold power unit securely and prevent
accidental loss of power. The power unit may
be
located
at
the equipment end of the cable or run
directly into the telephone
set
by conductors
separate from the mounting cord and connected
to
PSB terminals
30
and
31.
Refer to applicable
tables and Fig. 7 for particular type of installation.
When separate power conductors are used, disconnect,
insulate, and store the
(BL-
V)
and
(V-BL)
mounting
cord leads from
PSB
terminals
30
and
31.

HAN
DS
ET
CRADLE
----tr-:~-
ISS
4,
SECTION
503-603-101
COVER
SCREW
DETAIL REMOVED WHEN
0-160493
OR 0 · 180616
KIT
OF PARTS
IS
I
NSTA
LL
ED
Fig.
2-2872A2M
Telephone Set-Faceplate
and
Handset Removed
Danger:
Securely
attach
retaining
clamp
to
ac
outlet
using
outlet
cover
screw
BEFORE
attempting
to
install
958-type
power
unit.
When
re
moving
power
unit,
always
unplug
it
completely
from
tbe
outlet
BEFORE
attempting
to
remove
the
retaining
clamp.
This
will
prevent
the
possibility
of
a
loosened
retainer
cla
mp
or
metallic
outlet
cover
making
contact
with
tbe
ac
prongs
of
the
power
unit
when
paritally
withdrawn
from
outlet.
Do
not
us
e
841050818
or
similar
retaining
clamps
on
outlets
wbere
the
cover
mounting
screw
holds
the
duplex
outlet
in
the
box.
Note:
The 958-type power unit must be
located no closer than 1-112 feet from the
telephone
set
in order to prevent a noise
problem.
3.04 The station number card retainer
812558039
(P
-
25E803)
snaps into the faceplate
below
the dial.
3.05
The directory sheets (Fig.
2)
fit over the
buttons
of
the memory and
are
held
in
place
by
the faceplate. Additional sheets
are
available
in the directory sheet set,
840393672.
3.06
To
designate the buttons of the
635
-t
ype
6-button
key.
(1)
Use
Form
5837
tabs.
(2) Squeeze the sides of the
key
button caps
gently and remov
e.
(3)
Insert the tabs.
(4) Replace the caps
so
that
small bumps
on
side
of
caps
fi
t into small holes
on
sides
of
buttons.
In
sta
llation Check Procedure
3.07
Check telephone
set
installation per the
following tests(refer to
Part
5 for operation).
In case of failure, refer to Trouble Analysis, Table
N.
Page
7

SECTION
503
-603-101
T
ERMINA
L
BO
AR
D
TBl
BUZZER
M
O
UN~
I
N G
-.
\ -
---
Fig
.
3-2872A2M
Tel
eph
one
Set
With Faceplate,
Handset,
and
Handset
Cradle
Removed
Page
8

(1) Disconnect the power unit and manually dial
a known telephone number to check
that
the telephone operates correctly in the absence
of commercial power.
(2) Reconnect the power unit to ac outlet.
(3) With handset on-hook, record digits 1through
0 into consecutive memory locations, storing
one digit per memory. Fill all memory locations
except LAST NUMBER DIALED and location
immediately above
it [5.01 (4) through (7)].
(4) Manually dial CO dial test and ringer circuit
and simultaneously record into memory
location immediately above LAST NUMBER
DIALED button [5.01 (4) through (7)]. After
depressing RECORD OFF button, and when dial
test circuit is ready,
test dial frequencies by
manually dialing digits 1 through 0 into the
test
circuit.
(5) Momentarily hang up handset and automatically
dial the test circuit number recorded in Step
(4) by depressing button immediately above
LAST NUMBER DIALED button and proceed
as follows.
(a) Depress LAST NUMBER DIALED button.
Digits 1 through 0 will
be automatically
dialed into
test circuit. Verify that correct
signal is returned from
test circuit.
(b) Momentarily depress the memory buttons
used
in Step (3) in the same sequence in
which the digits were recorded. Verify
that
correct signal is returned from test circuit
after each series of numbers.
Tb.e battery and tb.e power unit must
be connected a minimum of five
minutes before doing Step (c).
(c) Momentarily disconnect the power unit
(for 5 to
10 seconds). After reconnecting
power unit, depress a memory button of a
memory location used in Step
(3), to verify
retention of memory.
(6) Dial the appropriate cod e for ring-back to
test the ringer.
ISS 4, SECTION 503-603-101
(7) Check operation of the logic reset switch
by pressing the RECORD button (RECORD
lamp will come on) and subsequently pressing
an unoperated line button. The RECORD lamp
must
go out.
(8) If equipped with one-touch calling option
(D-180493 Kit of Parts and speakerphone),
and with set in on-hook condition, depress the
memory button used in Step
(4) . The speakerphone
should
turn on, dial tone should be detected,
and the stored number should
be automatically
dialed.
OPTIONAL APPARATUS INSTALLATION
D-180492 Kit of Parts (With Speakerphone)
3.08 To install.
(1) Proceed as described in 3.16.
(2) Make connections per the appropriate Tables,
B through
E.
(3 ) Mount the kit assembly to the chassis with
the screws provided (Fig.
4). Beveled corner
of printed wiring board (PWB) should
be located
at lower right corner.
D-180493 Kit of Parts (Dial Tone Detector and
One-Touch Calling Switch)
3.09 To install.
(1) Remove the housing (3 . 21), and access PSB
terminal board
(3 . 17).
(2) Insert the board assembly from the back of
the set and locate as shown in Fig.
4, such
that the two tabs on the board assembly fit into
the slots in the bottom of the chassis.
(3) Lock the board into position by inserting
the self-threading screw through the right
side of the chassis.
(4) Mount the one-touch calling switch below
the dial with the
two screws provided.
Note: If switch for D-180818 Kit of Parts
is already present, the one-touch calling switch
can not
be installed. The PSB terminal where
the switch leads should
be connected (Table
Page 9

SECTION
503-603
-101
NETWORK
MOUN
TING
HOLES
FOR
0-180
492
OR
D-
80 494
K
IT
OF
PAR
TS
(0
PTI
0 NA
~I
TER
MINAL
1\R
EA
O
NE:
-TOUCH
CALLI
NG
SWITCH OF 0 - 18
0493
KI T OF PA
RT
S
(
OPTIONAL)
,
Fig. 4- 2872A2M Teleph
one
Set
-Dial Removed
To
Show
Te'"oinol Area
C
or
E)
shall be strapped together. (The
one-touch calling option cannot be turned off
by
th
e subscriber.)
(5) Make connections per Table
C,
E,
or
F.
(6) Break off the detail at
the
bottom of the
co
v
er
(Fig. 2) and trim edge as required.
(7) Verify correct operation of the option.
(8)
Reassemble set.
D-180494
Kit
of Ports {2/ 4-Wire Service)
3.10
To install.
(1)
Proceed
as
described in
3.17.
Page
10
(2) Make connections per Table
G.
(3) Mount the
kit
assembly to
the
chassis with
the
screws provided (Fig.
4).
D-
180818
Kit
of
Port
s {Record D
isa
ble
and
Dial
Intermix
Feature
s)
3.11
To
install.
(1)
Remove facep
late
(3.19).
(2)
Loosen the captive screw
at
the bottom of
the cover around the dial and remove
the
cover.
(3) Disengage the four captive memory mounting
screws
(r'
ig. 4).

IS
S 4,
SEC
TION 503-603-101
OIAL
CON N ECTOR
Fig.
S-2872A2M
Telephone
Set
, Internal View, Overall
(4)
Disengage the two captive dial mounting
screws and move dial aside.
(5)
Rotate left edge
of
the memory upward
as
sho
wn
by
Fig.
5.
Note:
If
set
is equipped with a 2870A
Memory, replace it with
2870B
Memory and
carefully pack and return the old memory
according to local procedures.
(6) Mount switch below dial using
the
two screws
provided.
Note:
If
the
one
-touch calling
sw
itch
{D-18049
3
Kit of
Parts)
has been provided,
it
must
be
removed. The PSB terminals where
the
switch
leads were connected (Table C
or
E)
must
be
strapped together. (The one-touch calling
option
<'.an
no longer
be
turned off by
the
subscriber.)
(7)
Co
nnect switch lead connectors to post
terminals on memory board per Table K.
(8) With feature switch in OFF position, verify
that
set
operates in normal manner:
• Numbers can
be
recorded into memory
• Numbers can
be
changed
• Numbers can be deleted from memory.
(9) Set feature switch to ON position and verify
feature provided.
Page
11

SECTION
503-603-101
e
Record disable feature, only.
(a)
RECORD
lamp will not light when
RECORD
button is depressed.
(b)
No
telephone numbers can
be
recorded,
changed, or deleted in memory.
(c) LAST NUMBER DIALED feature is
operative.
e Record disable and dial intermix features.
(a)
RECORD
lamp will not light when
record button is depressed.
(b)
No
telephone numbers can
be
recorded,
changed, or deleted in memory.
(c) LAST NUMBER DIALED feature is
disabled.
(d) Manually
anq
automaticallydialed digits
may be intermixed
(5.07)
.
(10)
Reassemble set.
Single-line Service
3.12
The
2870A2M
TOUCH-A-MATIC telephone
set is available from the factory as a single
line set. However, with the addition of a
2870B1
faceplate, the
2872A1M
and
2872A2M
telephone
sets may
be
converted to single line service as
follows.
(1
) Remove the faceplate, key collar, and all
buttons of the 635-type key.
(2)
Gain access to terminal area
(3
.
17)
.
(3)
Remove
the cradle
(3
.
20)
.
(4)
Make
correction per Table
L.
(5)
Reassemble
set
and install a
2870B1
faceplate
of the appropriate color.
Note:
If set was originally equipped with a
2872A1-87
faceplate, refer to
6.11
.
Head Telephone
S.t
3.13
To
install.
Page
12
(1)
Remove housing
(3
.
21
).
(2)
Access PSB terminal area
(3
.
17)
.
(3)
Remove cradle
(3
.
20).
(4)
Thread jack set cord through hole in rear
of
housing
and
make
connections
per
appropriate table provided for Plantronics Jackset.
(5)
Reassemble telephone set.
(6)
Insert head telephone
set
plug into jackset.
Other
optional
components
may
be
used
suclJ
as
SPOKESMAN'
loudspeaker
sets,
etc.
Refer
to
the
appropriate
section
for
connection
information
for
these
components.
COMPONENT
LOCATION
AND
ACCESS
INFORMATION
Location
of
Components
3.14
The components are located in three areas
as follows.
(a) Under the handset cradle (Fig.
3):
e
Buzzer
e
Ringer
e
Switchhook assembly
e
Handset jack
e
Terminal boards
(TB1
and
TB2).
(b) Under the faceplate, inside the
set
(Fig. 4
and
5)
:
e
Battery jack (Fig.
5)
e
Power supply (PSB) terminal area (Fig.
4)
e
Network (Fig.
4)
e
Options (Fig.
4)
:
D-180492
(relay kit for speakerphone)
D-180493
(dial tone detector and one-touch
calling switch kit)

D-
180494
(2/
4-wire rel
ay
kit
)
D-
1
80818
(r
eco
rd disable and dial intermix
f
eat
ur
e switch)
(c
) Bottom of telephone set (F
ig.
6).
• Battery.
M
ounting
Cord
3.15 The
D50BB-87
mounting cord is amphenol
ended at
the
equipment end and equipped
..
0
ISS
4,
S
ECT
ION
50
3-
603
-10
I
with
508-
type plugs for
ter
minating on the back
of the
635
-type
key
module
at
th
e telephone set
end. The conductors terminated in
the
508-type
plugs provide the major line ser
vice
requirements.
Spade-tipped conductors
ar
e provided for auxiliary
co
ntro
l functions or options and
are
ter
minated
directly
on
associated
eq
uipment, terminal
bo
ar
ds,
or
stored.
Note
: Sets manuf
act
ur
ed
pr
ior to fourth
quarter
1976
we
re equipped with
05
0AM
-87
mou
nting
co
rds. The major difference in the
cords is
that
TIP and RING contact strips
Fi
g. 6- 2
87
2A1M or
28
72
A2
M Teleph
one
S
et
, Bo
tt
om
View
Page
13

SECTION
503-603-101
Page
14
TABLE B
CONNECTIONS-
2872A1M
OR
2872A2M TELEPHONE SET WITH
38
SPEAKERPHONE
API'ARATUS
DESIG
T1
R1
A1
AG
LK
Tel Set R
or
R1
Ror
R1
B
or
B1
Bor
B1
Strap
Strap
CE
B+
0 ·
180492
SHa
Kit LK
of
Parts SHi
PFR
VDD
M1
P1
666B
-15V
TRMTR
s
(T7A
Cord)
Al
F1
LK
760A
LSPK SP1
(R2FKCord)
SP2
958-Type
AC1
Pwr
·
Unit
AC2
20128
Trnat
ACl
(Note
2)
AC2
• Inaulated
and
stored
.
t Terminal
on
network
.
LEAD
COLOR
V·G
G·V
V·S
s-v
BK
BK
8L
·
BK
BK·
8L
R·BL
BirR
G·W
8IrV
W·G
8-8K
BL
·R
BK·S
0.8K
Y·O
Q.Y
BK·O
G
R
CONNECT
TEL. SET FROM
(NOTE
11
CONTUNIT
(NOTE.
31
TOPSB
FROM TERM. 56A
668
•
2
19
1
• 11
28
10
12
2
•
Ft
5
11
•
17
11
36
18
34
9 25
17
33
8 24
PSB10
•
PSB20
•
10
16
16
17
18
20
21
4 7
13
8
14
16
3
18
29
19
2 17
11
35
34
20
33:j: 29:j:
27 27
36 36
:j:
To
reduce
loudspeaker
volume, move SP2 lead
to
terminal 24
(56
A)
or
30
(66B)
§
Inaulate
and
otore
(8IrV)
and
(V·
8L)
leads In
connector
cable
.
No
teo:
1.
Plug
telephone
oet
mounting
cord
into
149B
a
dapter
.
2.
Both
power
unit
and
2012B
tranatormer
must
be
connected
for
apeakerphone
operation
.
TO
1411ADPT
(D10R
CORDI
TERM.
SA
?A
A1
12A
llA
18
1A
2B
2A
3B
§
4B
§
3. When
55
A
control
unit
i.o
uoed,
it
must
be
in
the
type
modified
for TOUCH·TONE,
and
strap
tenninalo
20
and
21
(55A)
or
4
and
6
(558)
.

APPARATUS
Tel
Set
D-180493
Kit
of
Parts
(Note
4)
0·180492
Kit
of
Parts
(Note 2)
ISS
4,
SECTION
503-603-101
TABLE C
CONNECTIONS-
2872A1M
OR
2872A2M TELEPHONE
SET
WITH
ONE-TOUCH CALLING USING
38
SPEAKERPHONE
CONNECT
LEAD
TEL
SET FROM
(NOTE 1) CONT
UNIT
DESIG COLOR (NOTE 5)
TOPS8
FROM
TERM.
55
A
558
T1 V-G
•
2
19
1
R1 G-V
•
11 28
10
A1
12
2
AG V·S
•
Ft
5
11
LK S-V
•
17
11
35
SPO
o-v
•
34 3 18
Ror
R1
18
34
RorR1
9 25
Bor
B1
17 33
B
or
B1
8 24
Input
G-R 2
PB
0-BK
9
Input
G·R 11
LK Y-G
17
DT
Q-Y
19
VDD R-0 21
DR
Y-0 24
PL
Q-R 25
OTT
BL-Y 26
SPR
Y·BL 27
COM BK-Q 29
SPO G-Y 34
s 28
Swi
tch
s 29
CE BL-BK
10
B+
BK·BL 15
SHa R-BL
16
LK BL-R
17
SHi G-W
18
PFR
BL-V 20
VDD W-G 21
TO
1498
ADPT
(D10R
CORD)
TERM
.
SA
7A
A1
12A
llA
58
18
1A
28
2A
Page 15

SECTION 503-603-101
TABLE C
(Cont)
CONNECTIONS- 2872A1M OR 2872A2M TELEPHONE SET WITH
ONE -TOUCH CALLING USING 38 SPEAKERPHONE
CONNECT
LEAD
TEL SET FROM TO
APPARATUS (NOTE 1)
1498AOPT
CONTUNIT
DESIG (NOTE 5) (D10R
COLOR CORDI
FROM
TOPSB
TERM .
55 A 558
TERM .
Ml
Pl
6668
15V
TRMTR
s
(T7A Cord)
A1
Fl
LK
760A Lspk
SPl
(R2FK Cord)
SP2
958 - Type
AC1
PWT Unit AC2
20128 Trnsf
ACl
(Note 3)
AC2
•
Insulated and stored
t Terminal on network
8-8K
4 7
8L·R
13
8
8K ·S 11
16
0·8K 3
18
Y·O 29
19
G·Y 2
17
8K ·O
11
35
G 34
20
R 33:1: 29:1:
38 §
48 §
27 27
36 36
:1: To reduce loud speaker volume, move SP2 lead to terminal 24 (55 A) or 30 (558)
§ Insulate and store ( 8lr V) and (V· 8L ) leads in connector cable.
Notes:
l. Plug telep h one set mountin g cord into 1498 adapter .
2. When installing the 0·180492 Kit of Parts , disconnect (8K) strap from PS8 terminal 10, insulate a nd
s tore; d1sconnect (8K) lead from PS8 terminal 20; insulate and store .
3.
Both power ~nit and 20128 transfor m er must be connected for speakerphone operation .
4. When
mstalhng the D-180493 Kit of Parts, re mo ve ( 8K) strap leads from PS8 terminals 19 26 and 29
Insulate and store . ' ' '
5. When 55 A control unit is used, it must be the type modified for TOUCH-TONE , and strap terminals 20
and 21 (55A) or 4 and 5 (55 8 ).
were required with the D50AM-87, whereas
individual conductors of the
D50BB-87 connect
to the TIP and RING contacts of the 635-type
key.
Network Terminals
3.
16 For access to the network terminals.
(1) Remove the faceplate (3 .19 ).
(2) Loosen the captive cover screw at the bottom
of the white cover around the dial (Fig.
2).
Page 16
(3) Remove the cover.
(4) To replace the cover, the three tabs of the
cover (one
at the top center and one at each
side
just above the dial) must be aligned with
holes
in the chassis before the screw is refastened.
Failure to
do this will result in improper seating
of the faceplate.
Power Supply (PSB), Terminals
3.17
To access the terminal field on the power
supply board, proceed as follows.

(1) Remove the faceplate (3.19).
(2)
Loosen the captive cover screw
at
the bottom
of the white cover around the dial (Fig.
2)
.
(3)
Remove the cover.
(4)
Loosen the two captive screws
that
hold
the dial in place.
Note:
On
sets with metal dial brackets, the
screws will have to
be
removed.
(5)
Gently raise the dial and disconnect
12
position
plug from terminal board.
(6)
Rotate dial over onto the memory.
(7)
To
reassemble; reverse procedure.
(8)
To
replace the cover, the three tabs of the
cover (one
at
the top center and one
at
each
side
just
above the dial) must
be
aligned with
holes in the chassis before the screw is refastened.
Failure to
do
this will result in improper seating
of the faceplate.
Une
Key
Removal
3.18
To remove, use the following procedure.
(1)
Remove faceplate
(3.19)
.
(2)
Push the key toward the
rear
of the set to
unlock
it
from the tabs.
(3)
Raise the metal plate of the key
just
above
the tabs and move the key toward the left,
then raise the
right
end of the key until it clears
the chassis of the set.
Caution:
Do
not
damage
contact
strips
wbicb
protrude
from
bottom
rigbt
side
of
key
or
logic
reset
switcb
attached
on
HOLD
side
of
key.
(Tbese
contact
strips
will
only
be
found
on
sets
equipped
witb
D50AM-87
mounting
cords.)
(4)
Lift the
key
completely out of the set.
(5) Replace
key
by
reverse procedure.
ISS
4,
SECTION
S03-603-101
Faceplate Removal
3.19
Removal will differ depending
on
faceplate
provided.
(a) The
2872B1
faceplate is held
in
place by a
spring clip attached to the
870A1U
upper
housing. To disengage the faceplate, lift up
the tab which protrudes from the center of the
back edge of the faceplate.
Note:
The
2872B1
faceplate is not a direct
replacement for the
2872A1-87
faceplate.
An
870A1U
upper housing is also required with
the
2872B1
faceplate (see 6.
11).
(b) The
2872A1-87
faceplate is held
in
place
by
two snaps bonded to the faceplate and aligned
to fit holes in the chassis.
To
remove the
faceplate, grasp
it
by
any convenient edges and
lift.
Handset Cradle Removal
3.20
To
remove the handset cradle from the
housing, proceed as follows.
(1)
Remove the faceplate
(3
.
19),
and place the
handset aside.
(2) Remove upper housing, if provided,
[3
.
21(b)).
(3)
Disengage the captive cradle screws located
in
the two tabs on the cradle (Fig.
2).
(4)
Lift the cradle,
by
pulling up
on
the plunger,
and remove.
(5)
Replace the handset cradle
by
sliding
it
sideways to engage the clips with the mating
tabs in the side of the housing.
Caution:
Tbe
plunger
must
be
beld
from
tbe
top
side
of
tbe
cradle
as
it
is
slid
into
position
to
prevent
damage
to
tbe
switcbbook
arm.
(6)
Refasten the captive cradle screws.
Housing Removal
3.21
To
remove, proceed as follows.
(a)
Lower
bousing.
Page
17

SECTION
503-603-1
01
(1)
Unplug the handset cord,
at
the telephone
set end and remove handset.
(2)
Remove
the faceplate
(3
.
19)
.
(3
) Remove the handset cradle
(3
.
20).
Caution:
Attempting
to
remove
the
housing
without
removing
the
handset
cradle
may
damage
the
switchhook
arm.
(4)
Disengage the four captive housing screws
(Fig.
2)
located in each corner of the upper
housing.
(5)
Separate the housing from the telephone
set base.
(6)
Feed mountingcord through hole in bottom
of
housing as housing
is
removed.
(7)
Before replacing the housing, lift the set
to check
that
the shoulders of the battery
jack are against the two tabs
on
the chassis.
Misalignment may cause
the
bottom of the
housing to
bow
.
(8)
When replacing the housing, keep the
handset jack from being trapped between
the housing and the chassis.
(b)
Upper
housing.
(1)
Remove the faceplate
(3.19)
.
(2)
Disengage
the
captive housing screws
located in each corner of the upper housing
(Fig.
2).
This will release the lower housing.
(3
) Pull the upper housing away from the
chassis as each housing screw
is
backed
out. This will separate the upper housing
from the chassis.
(4)
If
necessary, thread screws out of housing.
(5)
To
reassemble, reverse procedure.
4.
CONNECTIONS
4.01 Telephone
set
connections are shown in Fig.
8 and Table I.
Page 18
Caution:
Some
conductor
assignments
are
not
standard
(Table
1).
4.
02
Refer to Table A for connection reference
for all options.
4.
03
A partial functional schematic is shown
on
Fig.
14.
5.
OPERATION
Record A Number Into Memory
5.01
To
record.
(1
) Remove the faceplate (
3.19
).
(2)
Write or type the desired name and telephone
number for a selected memory button
on
the associated position of the directory sheet.
(3)
Replace the directory sheet and faceplate.
(4)
Depress the
RECORD
button. The
RECORD
lamp adjacent to the
RECORD
button will
light.
(A
number can
be
called and recorded
simultaneously
by
lifting handset before depressing
the RECORD button.)
Note:
If set is equipped with the
D-180818
Kit of Parts, switch must
be
placed in the
OFF position.
(5)
Depress the specific memory button adjacent
to the desired telephone number listed
on
the directory sheet.
(6)
Manually dial the desired telephone number
If
an access code and pause for second dial
tone is required.
(a) Dial the access digit(s) for the outside
line.
(b) Push
theW
AIT
button when the RECORD
lamp relights. (The WAIT entry counts
as one digit.)
(c)
Dial the telephone number.
Note:
A number up to
15
digits in length
may
be
recorded. The
RECORD
lamp will
go
out momentarily as each digit is dialed.
If
exactly
15
digits are recorded, the
RECORD

lamp will
go
out and stay out, indicating
that
the dialer has been reset.
If
a memory button
has not been depressed, the
RECORD
lamp
will
go
ou
t when the first digit is dialed and
recording operation will
be
voided.
(7)
Depress the
RECORD
OFF button if less
than
15
digits are recorded. The
RECORD
lamp will
go
out. The dialer will
be
reset. ·The
number
is
now
stored in the selected memory.
The dialer will also
be
reset
by
a switchhook,
line key, or speakerphone operation.
Change
A
Number
In
Memory
Note:
If
set is equipped with a
D-180818
Kit of Parts, switch must
be
in OFF position.
5.02
Whenever a new number is recorded in a
previously used memory position,
it
will
automatically replace the previously stored number.
Delete A
Number
From Memory
Note:
If
set
is equipped with a
D-180818
Kit of Parts, switch must
be
in OFF position.
5.03
Complete the following operations
in
succession.
(1)
Depress the
RECORD
button.
(2)
Depress the memory button corresponding
to the name and number to
be
deleted.
(3)
Depress the
RECORD
OFF button.
Automatically Dial A Number From Memory
5.04
To
automatically dial a number.
(a) For factory-wired sets
go
off-hook, listen
for dial tone,
and
depress
the
desired
memory button. If WAIT input has been recorded,
automatic dialing will stop. When second dial
tone
is
heard, depress memory button again to
complete automatic dialing.
(b) For sets equipped with the dial tone detector
only,
go
off-hook, listen for dial tone, and
depress the desired memory button.
(c) For sets equipped with the one-touch calling
option (with speakerphone and dial tone
detector), simply depress the memory button.
ISS
4,
SECTION
503-603-101
LAST
NUMBER
DIALED
Feature
Note:
If
set is equipped with a
D-180818
Kit of Parts, and dial intermix feature
is
provided, switch must
be
in OFF position.
S.05
The
TOUCH-A-MATIC
telephone
set
automatically records into the
LAST
NUMBER
DIALED position (Fig.
1)
any number dialed using
the standard telephone dial. Each number in the
LAST NUMBER DIALED position is automatically
replaced
by
the next number manually dialed.
Although the unit is recording, the
RECORD
lamp
does not light
at
any time during this operation.
5.06
Operation of LAST NUMBER DIALED
feature.
(a) With
no
access digit(s) required.
(1)
Go
off-hook.
(2)
Listen for dial tone.
(3}
Manually dial telephone number.
(4)
To
redial same number automatically.
(a) For factory-wired sets,
go
off-hook,
listen for dial tone and depress LAST
NUMBER DIALED button.
(b) For sets equipped with the dial tone
detector only,
go
off-hook, listen for
dial tone, and depress the LAST NUMBER
DIALED button.
(c) For sets equipped with
the
one-touch
calling option (with speakerphone and
dial tone detector}, simply depress
the
LAST NUMBER DIALED button.
(b) When an access code and pause for second
dial tone is required.
(1)
Go
off-hook.
(2)
Listen for dial tone.
(3}
Dial access digit(s}.
(
4)
Depress WAIT button, after second dial
tone is heard.
Page
19

SECTION
503-603-101
(5)
Manually dial telephone number.
(6)
To
redial same number automatically.
(a) For factory-wired sets,
go
off-hook,
listen for dial tone and depress LAST
NUMBER DIALED button. Automatic
dialing will stop
at
the recorded WAIT
input. When second dial tone is heard,
depress LAST NUMBER DIALED button
again to complete automatic dialing.
(b) For sets equipped with the dial tone
detector only,
go
off-hook, listen for
dial tone, and depress LAST NUMBER
DIALED button.
(c) For sets equipped with the one-touch
calling option (with speakerphone and
dial tone detector), simply depress
the
LAST NUMBER DIALED button.
End-to-End Signaling
5.
07
For end-to-end signaling (such as
data
transmission) this set has the capability to
intermix manual and automatic dialing. This can
be
accomplished if the following procedures are
observed.
Note:
If
the telephone
set
is to
be
used
for end-to-end signaling, Voption (with polarity
guard) shall
be
used, (Fig.
SB)
.
(1)
If
the telephone set is equipped with the
one-touch calling option the initial number
must
be
dialed automatically (even if the one-touch
calling switch is in the OFF position). This
allows the dial tone detector to complete its
function and then additional numbers may be
dialed automatically or manually.
(a)
Standard
Operation:
If,
at
any time,
information is keyed in manually, the
RECORD OFF button must be depressed
before another number can
be
dialed from
memory. (The
RECORD
lamp will not light
at
any time but depressing the RECORD
OFF button will remove the set from the "last
number dialed" mode and allow additional
automatic dialing
.)
(b)
Dial
Intermix
(D-180818
Kit
of
Parts):
With the switch in the
ON
Page
20
position, manually and automatically dialed
digits may
be
intermixed as desired. Operation
of the RECORD OFF button is not required.
Note:
In this mode, the
RECORD
button
and the LAST NUMBER DIALED feature are
inoperative.
6. MAINTENANCE
6.01
In case of power failure, the automatic dialing
feature cannot
be
used. The battery retains
the number associated with each of the memory
buttons for
at
least
24
hours.
If
power loss exceeds
24
hours, the numbers may have to
be
rerecorded.
Trouble
Analysis
6.02
When trouble is encountered, the subsequent
procedure should
be
followed.
(1)
Confirm improper operation either as a basic
telephone
set
or as an automa
ti
c dialer
(Part
5).
(2)
Check for improper connections.
(3)
Refer
to
Table
N,
and the following paragraphs.
(4)
If removal of set is required, proceed as
follows.
(a) Disconnect telephone
set
.
(b)
Unplug battery.
(c)
Place battery plug sideways into housing
slot below battery jack and tape into
place.
Caution:
Failure
to
restrain
plug
can
result
in
plug
damage
necessitating
battery
replacement.
Battery
6.03
The
KS-20390L2
and
L4
batteries are not
completely interchangeable. The List 2
battery may
be
used in both sets but the List 4
battery
should only
be
used in
the
2872A2M
telephone set. Either battery has an expected life
of about 4 years.
It
can
be
replaced without loss
of memory provided
that
commercial
ac
power to

ISS
4,
SECTION
503-603-101
the set
is
continuously maintained.
To
replace
Dial
the battery, proceed as follows (Fig.
6)
.
(1)
Tilt the front of the set up.
(2)
Unplug the battery.
(3)
Loosen captive screw
on
the battery support.
(4)
Remove battery support.
(5)
Remove
battery.
(6)
Install
new
battery.
(7)
When battery has been connected
at
least
five
minutes, check memory retention
by
momentarily disconnecting ac power and then
automatically dialing a known telephone number.
Memory
6.
04
The memory may
be
replaced in the following
manner.
Note:
Removal
of
the memory results in
loss of stored telephone numbers.
(1)
Remove the faceplate
(3
.
19)
.
(2)
Loosen the four captive memory mounting
screws (Fig.
4)
.
(3)
Rotate the left edge
of
the memory upward
as shown in Fig. 5.
(4)
Disengage the two connectors
by
pulling
on
them perpendicular to the printed wiring
board.
(5)
Replace the memory
by
engaging the dial
connector first. The dial connectors are
keyed, one position is filled and should fit over
the vacant position in the row
of
pins. The flat
power supply cable should not
be
twisted.
It
should form a
loop
as shown in Fig. 5 when
connected to the board.
(6)
Reassemble set.
(7)
Test per 3.
07.
6.05
To
replace.
(1)
Proceed per 3.
17
.
(2)
Loosen the four captive mounting screws of
the memory (Fig.
4).
(3)
Gently raise the left side of the memory
and rotate to position shown in Fig.
5.
This
will expose 10-position dial connector.
Caution:
Do
not
remove
tb.e
power
supply
connector
in
tb.e
process
of
changing
tb.e dial,
since
tb.is
will
result
in
complete
loss
of
stored
telephone
numbers.
(4)
Carefully disengage the dial connector
by
pulling on
it
perpendicular to the printed
wiring board.
(5)
Lift the dial out.
(6)
To
replace a new dial, reverse the previous
steps. The connectors are keyed to orient
them relative to the pins. Observe the correct
orientation and
do
not force the connection.
6-BuHon Une Key
6.06
To
replace.
(1)
Remove key per 3.
18
.
(2)
Access PSB terminal area per 3.
17
.
(3)
Disconnect logic
reset
leads from PSB
terminals
14
and
29
.
(4)
Remove the 508-type plugs and (if provided)
the two contact strips from the back of the
key.
(
5)
Install
new
key
.
(6
) Reassemble the set.
(7)
Test for operation of the logic reset switch
[3
.
07(7))
.
Page
21

SKTION
503-603-1
01
Ringer
6.07
To
replace.
(1)
Remove the faceplate
(3.19)
and place handset
aside.
(2)
Remove upper housing, if provided,
(3
.
21(b)].
(3)
Remove the cradle
(3.20).
(4)
Disconnect the ringer leads (Fig.
81)
.
(5)
Tilt the front of the set up.
(6)
Unfasten ringer mounting screws (Fig.
6)
.
(7)
Remove ringer.
(8)
Replace
new
ringer and assemble in reverse
order. The leads should
be
routed as shown
in Fig. 3 to prevent contact with the gong and
subsequent damping of the ringer output. Dial
ringback code to
test
ringer.
(9)
Reassemble set.
Buzzer
6.08
To
replace the buzzer.
(1)
Remove the faceplate
(3.19),
and place handset
aside.
(2)
Remove upper housing, if provided,
(3
.
21(b)].
(3)
Remove the cradle
(3.20).
(4)
Remove the buzzer mounting screw.
(5)
Remove the mounting screw and spacer for
TB1
(Fig.
3).
(6)
Move
board
TB1
to gain access to
the
appropriate terminals
on
TB2
.
(7) Remove appropriate leads (Fig. 8H).
(8)
Reassemble. When replacing
TB1
, locate
its tabs in the slots of the chassis before
refastening the
TB1
mounting screw.
Page
22
Handset
Jack
6.
09
To
replace the
616B
handst jack.
(1)
Remove the faceplate
(3.19),
and place handset
aside.
(2) Remove upper housing, if provided,
(3
.
21(b)].
(3)
Remove the cradle
(3
.
20)
.
(4) Remove the mounting screw and spacer for
TB1
(Fig.
3)
.
(5)
Move
board TBl to gain access to the
appropriate terminals on
TB2
.
(6)
Disconnect the appropriate leads (Fig. 8H),
and remove jack.
(7) Reassemble. When replacing
TB2,
locate
its tabs in the slots of the chassis before
refastening the
TB1
mounting screw.
Handset
6.10
A defective
G15A
handset may
be
replaced
or changed to a modular amplifying handset
(G6BM,
G7BM
,
or
G8BM)
by
unplugging the H4DU
cord and inserting
it
into the new handset.
To
replace the
G15A
handset with a nonmodular
amplifying handset
(G6B,
G7B,
or
G8B)
proceed
as follows.
(1)
Unplug H4DU handset cord
at
telephone set
end.
(2)
Remove faceplate
(3.19),
and place handset
aside.
(3)
Remove upper housing, if provided,
[3
.
21(b)]
.
(4) Remove handset cradle
(3.20).
(5)
Disconnect
616B
handset jack
(6.09).
(Jack
may
be
removed or stored
just
to
right
of
ringer
.)
(6)
Insert
spade-tipped end of handset cord
through hole
in
the side of the housing.
(7)
Attach stayboard hook to bottom of chassis
(Fig.
3).