four-wire full-duplex Type 3002 Private-Line Service with C1 conditioning and a Western
Electric Data Set 202D2 * are required. In
either case, alternate voice-data capability
with key-controlled ringing is recommended.
The Data Set 202D2* must be wired and equipped
by the local common carrier to provide full­
duplex data operation and a one-way, low-speed
reverse channel to accommodate signals trans­
mitted from the 2703 to the 2712. This wiring
arrangement must be ordered by the customer
at the time he places his data set order. NOTE: Where the line conforms to the specifications in the SRL manual A24-,:\435** for Limited-Distance Line Adapter Type
1, the IBM Line Set 1A (#4686) or 1B (#4687) can be used in
place of a data set for attachment of 2740 or 2741 terminals. \Vhere the line conforms to specifications in the cited manual
for Limited-Distance Line Adapter Type 2, the IBM Line Set 2 (#4688) can be used to attach IBM 1030, 1050, 1060, 1070, 2740, and 2741 systems and terminals.
4. For each line servicing synchronous term ina I
devices, the following is required;
a. At 1200 bps (synchronous), a Western
Electric Data Set 202D1 * is required.
b. At 2000 bps, a Western Electric Data Set 201A3* and Type 3002 Private-Line Service with C2 conditioning or better
are reqUired.
c. At 2400 bps, a Western Electric Data Set 201B1 * and Type 3002 Private-Line Ser­ vice with C2 conditioning or better are re­
quired. For operation at 2400 bps using
Western Electric Data Set 201Bl * on Type 3002 Private-Line Service with C2 condi­
tioning, there are additional restrictions
and limitations to the facility and opera­
tions. See the SRL manual, General In­
formation--Binary Synchronous Communi-· cations, Form A27 -3004, for details. 3004, for details.
d. At 4800 bps, Modems may be attached by
the customer under the provisions of the
'Mult.i.ple Supplier System Policy'; con­
sult your IBM Marketing Representative.
5. For each ',;orld Trade line servicing synchro­
nous terminal devices, one of the following
is required: '" or equivalent "'* Form .\24-3435-2, or subsequent revisions a, IBM Modems--At 600 or 1200 bps, an IBM
3976 Model 3 or an IBM 3977 Model 1 or
2 is required. At.speeds up to 2400 bps
(bit rate must match clock feature), an
IBM 3977 Model 2 is required.
b. PTT Modems--At 600 or 1200 bps, the United Kingdom uses GPO Datel 1 Model
5, Germany uses PTT D1200S (GH-2011
Model 5), and Sweden uses PTT GH- 2002B and PTT GH-2002C.
c, At 4800 bps, consult the appropriate IBM
Teleprocessing Coordinator for Modem
information.
d. NTT Modem--At 600 or 1200 bps, Japan
uses NTT Modem DT1203.
Common-Carrier Leased Private-Line Telegraph Service 1. On common-carrier Type 1002 or 1005 private­
line service, common-carrier data sets are
not required. However, a 62. 5-milliampere
neutral dc loop must be provided by the com­
mon carrier for each telegraph channel where
operation is via Te legraph Line Set (#7897)
2. On common-carrier 150-baud Type 1006 pri­
vate-line service, appropriate channel termi­
nation must be provided by the common carrier.
Western Union TyPe 3002 Channels with C1 Condi­
tioning
1. An IBM Line Adapter (#4639 for two-wile, or
#4647 for four-wire) on a 2711 Line Adapter Unit is required for each start/stop channel
termination. For operation at 1200 bps (syn­
chronous), a Western Electric Data Set 202D1*
is required for each channel termination.
Western Union Type 3002 Channels with C2 Condi­
tioning
1. At 2400 bps, a Western Electric Data Set 201B1 * is required for each line servicing
synchronous terminals.
69

World Trade Common-Carrier Private Line Tele­ graph Circuits 70 1. World Trade Single Current Line Set (#2829)
allows direct attachment of 40ma, 2 wire,
single-current telegraph circuits at 50 or 75
bps.
2. World Trade Double-Current Line Set (#2831)
allows attachment of 2 or 4 wire double­
current telegraph circuits at 50,75, or 100 bps via IBM 3945 Model 11 Telegraph Line
Termination. PRI\'ATELY OWNED COMMUNICATIONS FACILITIES
The privately owned communications facility must
be equivalent to one of the previously described
common-carrier facilities. If the facility conforms
to the SRL manual A24-3435** specifications for
Limited-Distance Line Adapter Type 1, IBM Line Set 1A or 1B (#4686 or '#4687) may be used; for
Limited-Distance Line Adapter Type 2, IBM Line Set 2 (#4688) may be used in place of data sets.