Black Box IC714A-449-R2 User manual

CUSTOMER
SUPPORT
INFORMATION
Order toll-free in the U.S.: Call 877-877-BBOX (outside U.S. call 724-746-5500)
FREE technical support 24 hours a day, 7 days a week: Call 724-746-5500 or fax [phone]
Mailing address: Black Box Corporation, 1000 Park Drive, Lawrence, PA 15055-1018
Web site: www.blackbox.com • E-mail: [email protected]
MAY 1997
IC714A-449-R2 IC714AE-449-R2 IC714A-48-449-R2
IC714A-530-R2 IC714AE-530-R2 IC714A-48-530-R2
IC714A-V35-R2 IC714AE-V35-R2 IC714A-48-V35-R2
IC714A-X21-R2 IC714AE-X21-R2 IC714A-48-X21-R2
G.703 Codirectional Converter
G.703↔V.35 CODIRECTIONAL
PWR TD RD LOS TEST ERR PATT
REM
ANA
DIG

1
FCC AND DOC/MDC RFI STATEMENTS
FEDERAL COMMUNICATIONS COMMISSION
AND
INDUSTRY CANADA
RADIO FREQUENCY INTERFERENCE STATEMENTS
This equipment generates, uses, and can radiate radio-frequency energy, and if not
installed and used properly, that is, in strict accordance with the manufacturer’s
instructions, may cause interference to radio communication. It has been tested
and found to comply with the limits for a Class A computing device in accordance
with the specifications in Subpart B of Part 15 of FCC rules, which are designed to
provide reasonable protection against such interference when the equipment is
operated in a commercial environment. Operation of this equipment in a
residential area is likely to cause interference, in which case the user at his own
expense will be required to take whatever measures may be necessary to correct
the interference.
Changes or modifications not expressly approved by the party responsible
for compliance could void the user’s authority to operate the equipment.
This digital apparatus does not exceed the Class A limits for radio noise emission from
digital apparatus set out in the Radio Interference Regulation of Industry Canada.
Le présent appareil numérique n’émet pas de bruits radioélectriques dépassant les limites
applicables aux appareils numériques de la classe A prescrites dans le Règlement sur le
brouillage radioélectrique publié par Industrie Canada.

2
G.703 CODIRECTIONAL CONVERTER
NORMAS OFICIALES MEXICANAS (NOM)
ELECTRICAL SAFETY STATEMENT
INSTRUCCIONES DE SEGURIDAD
1. Todas las instrucciones de seguridad y operación deberán ser leídas antes de
que el aparato eléctrico sea operado.
2. Las instrucciones de seguridad y operación deberán ser guardadas para
referencia futura.
3. Todas las advertencias en el aparato eléctrico y en sus instrucciones de
operación deben ser respetadas.
4. Todas las instrucciones de operación y uso deben ser seguidas.
5. El aparato eléctrico no deberá ser usado cerca del agua—por ejemplo, cerca
de la tina de baño, lavabo, sótano mojado o cerca de una alberca, etc..
6. El aparato eléctrico debe ser usado únicamente con carritos o pedestales que
sean recomendados por el fabricante.
7. El aparato eléctrico debe ser montado a la pared o al techo sólo como sea
recomendado por el fabricante.
8. Servicio—El usuario no debe intentar dar servicio al equipo eléctrico más allá
a lo descrito en las instrucciones de operación. Todo otro servicio deberá ser
referido a personal de servicio calificado.
9. El aparato eléctrico debe ser situado de tal manera que su posición no
interfiera su uso. La colocación del aparato eléctrico sobre una cama, sofá,
alfombra o superficie similar puede bloquea la ventilación, no se debe colocar
en libreros o gabinetes que impidan el flujo de aire por los orificios de
ventilación.
10. El equipo eléctrico deber ser situado fuera del alcance de fuentes de calor
como radiadores, registros de calor, estufas u otros aparatos (incluyendo
amplificadores) que producen calor.
11. El aparato eléctrico deberá ser connectado a una fuente de poder sólo del
tipo descrito en el instructivo de operación, o como se indique en el aparato.

3
NOM STATEMENT
12. Precaución debe ser tomada de tal manera que la tierra fisica y la polarización
del equipo no sea eliminada.
13. Los cables de la fuente de poder deben ser guiados de tal manera que no
sean pisados ni pellizcados por objetos colocados sobre o contra ellos,
poniendo particular atención a los contactos y receptáculos donde salen del
aparato.
14. El equipo eléctrico debe ser limpiado únicamente de acuerdo a las
recomendaciones del fabricante.
15. En caso de existir, una antena externa deberá ser localizada lejos de las lineas
de energia.
16. El cable de corriente deberá ser desconectado del cuando el equipo no sea
usado por un largo periodo de tiempo.
17. Cuidado debe ser tomado de tal manera que objectos liquidos no sean
derramados sobre la cubierta u orificios de ventilación.
18. Servicio por personal calificado deberá ser provisto cuando:
A: El cable de poder o el contacto ha sido dañado; u
B: Objectos han caído o líquido ha sido derramado dentro del aparato; o
C: El aparato ha sido expuesto a la lluvia; o
D: El aparato parece no operar normalmente o muestra un cambio en su
desempeño; o
E: El aparato ha sido tirado o su cubierta ha sido dañada.

4
G.703 CODIRECTIONAL CONVERTER
DISCLAIMERS
This manual contains information proprietary to the manufacturer. No part
of this publication may be reproduced in any form whatsoever without prior
written approval.
No representation or warranties for the fitness of these products for any
purpose other than those specifically mentioned in this manual are made
either by the manufacturer or its agents.
The manufacturer reserves the right to revise this publication and make
changes without obligation to notify any person of such revisions and
changes.
The manufacturer shall not be liable for any direct, indirect, special,
incidental, or consequential damages, whether based on contract, tort, or any
legal theory.
SAFETY WARNING
Always observe standard safety precautions while installing, operating, or
troubleshooting this product. To avoid the possibility of electrical shock,
disconnect the unit’s power cord from the power source before you remove
the unit’s cover.
TRADEMARKS USED IN THIS MANUAL
Any trademarks mentioned in this manual are acknowledged to be the property of the
trademark owners.

5
TABLE OF CONTENTS
Contents
Chapter Page
1. Specifications .............................................................................................. 7
1.1 G.703 Interface ...................................................................................... 7
1.2 Data-Communications Interface .......................................................... 7
1.3 Data-Communications Control Signals ............................................... 8
1.4 Other Physical Specifications ............................................................... 9
2. Introduction .............................................................................................. 11
2.1 Functional Description ....................................................................... 11
2.2 Timing Theory .................................................................................... 13
2.2.1 CCITT G.703 Signalling ............................................................ 13
2.2.2 G.703 Codirectional Timing ..................................................... 13
2.2.3 Tail-End Clocking ...................................................................... 17
2.2.4 G.703 Codirectional Rules ......................................................... 17
2.3 Rate-Conversion Rules ........................................................................ 19
2.4 Physical Description ............................................................................ 19
3. Installation .................................................................................................. 20
3.1 Unpacking ........................................................................................... 20
3.2 Site Requirements ............................................................................... 20
3.3 Setting Jumpers ................................................................................... 21
3.3.1 Overview ..................................................................................... 21
3.3.2 The Jumper-Setting Procedure ................................................. 23
3.4 Installation in 19-Inch Racks .............................................................. 23
3.4.1 Overview ..................................................................................... 23
3.4.2 Installing a Single Unit in a 19-Inch Rack ................................ 24
3.4.3 Installing Two Units in a 19-Inch Rack ..................................... 25
3.5 Connecting Power and Data Cables .................................................. 27
3.5.1 Power Connection ..................................................................... 28
3.5.2 G.703 LINE Connection ............................................................ 29
3.5.3 DTE Connection ........................................................................ 30
3.5.4 Async Secondary-Channel Connection .................................... 30

6
G.703 CODIRECTIONAL CONVERTER
Contents (continued)
Chapter Page
4. Operation ................................................................................................... 31
4.1 Front-Panel Controls and LEDs ......................................................... 31
4.2 Operating Instructions ....................................................................... 33
4.2.1 Turn-On Procedure ................................................................... 33
4.2.2 Activating Loops ......................................................................... 33
4.2.3 Turn-Off Procedure ................................................................... 33
4.3 Diagnostic Loops ................................................................................. 33
4.3.1 The Modem Self-Test ................................................................. 34
4.3.2 Local Analog Loopback ............................................................. 35
4.3.3 Remote Digital Loopback .......................................................... 36
4.3.4 Local Digital Loopback ............................................................. 37
4.4 Calling Black Box ................................................................................ 38
4.5 Shipping and Packaging ..................................................................... 39
Appendix: Pinouts ............................................................................................. 42

7
CHAPTER 1: Specifications
1. Specifications
1.1 G.703 Interface
Type — Codirectional 64-kbps
Line — 4-wire, 19- to 26-gauge
Range — Up to 800 meters (1⁄2mile) over 24-gauge wire
Impedance — 120 ohms nominal
Balance — Greater than 45 dB (up to 256 kHz)
Greater than 35 dB (up to 384 kHz)
Return Loss — Less than 20 dB (up to 128 kHz)
Less than 14 dB (up to 384 kHz)
“Pulse” Amplitude — 1.0 V nominal
“Zero” Amplitude — 0 V ± 0.1 V max
Clock Frequency — 64 kHz
Frequency Tracking — ± 500 ppm
Connector — 5-screw terminal block
Jitter Performance — To G.823 requirements
1.2 Data Communications Interface
Type — Models with “-449” affix: EIA RS-530 adapted to
EIA RS-449 (ITU-TSS V.11/V.36/EIA RS-422/423);
Models with “-530” affix: EIA RS-530;
Models with “-V35” affix: ITU-TSS V.35;
Models with “-X21” affix: ITU-TSS X.21/V.11

8
G.703 CODIRECTIONAL CONVERTER
Data Rate — 64, 56, or 48 kbps, user-selectable
Spare Bandwidth — [at 56 or 48 kbps:] “1’s” density bit stuffing as per
ITU-TSS V.110; additional asynchronous channel
at 1200 bps; or transfer of RTS to DCD control
signal, end-to-end
Connector — Models with “-449” affix: DB25 female cabled to
DB37 female;
Models with “-530” affix: DB25 female;
Models with “-V35” affix: 34-pin M-block female;
Models with “-X21” affix: DB15 female
1.3 Data-Communications Control Signals
Functional — DCD, 64 kbps: ON when Rx pair contains required
violations, OFF when the Rx pair does not
contain required violations;
DCD, 48 or 56 kbps: When the Rx pair contains
the required violations, the DCD signal reflects
the state of the remote RTS; DCD is always OFF
when no violations are detected;
CTS output: ON after RTS ON, with delay; OFF
when RTS OFF, or during Loss of Signal
condition;
DSR output: ON (+V) when power is available
Clock Source — From G.703 Receive pair (LBT), from DCE (EXT),
or from internal source (INT), user-selectable;
If LBT, three sub-options are user-selectable:
Unit is DCE and RC and TC signals are outputs
from the unit to the local DTE (LBT-DTE);
RC signal is an output from the unit to the local
DTE, but TC signal is an input from a tail-
circuit DCE (LBT-DCE); or
X.21 only: Unit is DTE and RC and TC signals
are both inputs to the unit from the local DCE
(LBT-DCE21)

9
CHAPTER 1: Specifications
1.4 Other Physical Specifications
Compliance — EMI/RFI: FCC Part 15 Class A, DOC Class/MDC
classe A
Safety: IEC 380
Standards — Diagnostics: ITU-TSS V.52 and V.54
Internal Memory — 32 bits of RAM divided into (2) independent 16-bit
buffers
User Controls — (4) Front-mounted pushbuttons: Local Digital
Loopback (DIG), Local Analog Loopback (ANA),
Remote Digital Loopback (REM), and Test
Pattern (PATT);
(5) Internal jumpers: Connect/disconnect grounds,
clock source, LBT clock-signal derivation, data
rate, and V.54 delay;
(1) Internal solder contact to connect grounds;
Loopback tests can also be triggered by interface
signals from local DTE
Diagnostics — Local digital loopback; local analog loopback (V.54
Loop 3); remote digital loopback (V.54 Loop 2);
511-bit V.52 BERT; all user-initiated and user-
terminated
Indicators — (6) Front-mounted LEDs: Power (PWR), Receive
Data (RD), Transmit Data (TD), Loss of Signal
(LOS), Test (TEST), and Error (ERR)
Power — IC714A models : Directly from outlet through
detachable 6-ft. (1.8-m) power cord (included):
Optimal Input: 115 VAC, 60 Hz, 0.2 amps;
Input Ranges: 103.5 to 126.5 VAC, 47 to 63 Hz;
IC714AE models: Directly
from outlet through
detachable 6-ft. (1.8-m) power cord (included):
Optimal
Input: 230 VAC, 50 Hz, 0.1 amps;
Input Ranges: 207 to 253 VAC, 47 to 63 Hz;

10
G.703 CODIRECTIONAL CONVERTER
Power (cont’d) — IC714A-48 models: –48 VDC directly from source
through detachable power cord (not included except
for output-jack components);
All models: Consumption: 25 watts
Fuse — IC714A models: 0.2-amp;
IC714AE models: 0.1-amp;
IC714A-48 models: 250 V, 200 ma
Isolation Voltage — 1500 VAC between G.703 interface and each of
these: data-communication interface, AC mains
(transformer primary), and frame ground;
also 1500 VAC betwen AC mains (transformer
primary) and each of these: data-communication
interface and frame ground
NOTE: This measurement was derived by testing for
one minute.
Maximum Altitude — 8000 ft. (2348.4 m)
Temperature
Tolerance — 32 to 122°F (0 to 50°C)
Humidity
Tolerance — Up to 95% noncondensing
Enclosure — High-impact plastic
Size — 1.8"H x 7.6"W x 9.6"D (4.6 x 19.3 x 24.3 cm), but the
unit’s pushbuttons protrude up to 0.3" (66 mm)
from the front panel and the connectors protrude
up to 0.8" (1.9 cm) from the rear panel
Weight — Net: 3.7 lb (1.7 kg); Shipping: 6 lb. (2.7 kg)

11
CHAPTER 2: Introduction
2. Introduction
2.1 Functional Description
The G.703 Codirectional Converter converts the ITU-TSS (CCITT) G.703
codirectional (line) interface to standard data-communication interfaces. The
Converter can perform two conversions:
•Electrical Conversion — from G.703 to ITU-TSS V.35, V.36/V.11 (EIA RS-
449/422/423), X.21/V.11, or EIA RS-530.
• Data-Rate Conversion — from 64 kbps to 48 or 56 kbps, when required.
The electrical and rate conversions enable you to connect DCE devices to
PCM transmission equipment.
Different models of the Converter have different interface connectors
depending on which data-commu-nication interface they support:
•
Models whose product codes in- clude “-449” support EIA RS-422/ 423/ITU-
TSS V.11 signaling on the EIA RS-449/ITU-TSS V.36 physical interface.
The interface connector mounted on these units is an RS-530 DB25 (see
the next paragraph); an included adapter cable patches these to a 37-pin
D-subminiature (“DB37”) female interface connector.
• Models whose product codes include “-530” support the EIA RS-530
physical/electrical interface (with ITU-TSS V.11-compatible signal levels);
they have a 25-pin D-subminiature (“DB25”) female interface connector.
• Models whose product codes include “-V35” support the ITU-TSS V.35
physical/ electrical interface; they have a 34-pin M-block (“M/34”) female
interface connector.
• Models whose product codes include “-X21” support
ITU-TSS V.11 signaling on the ITU-TSS X.21 physical interface; they have
a 15-pin D-subminiature (“DB15”) female interface connector.
Operating full-duplex at a transmission rate of 64 kbps, the Converter has a
range of up to 800 meters (1⁄2mile) from the PCM equipment. The unit’s
receive-timing source is the recovered clock from the CCITT G.703 receive
pair. You can set a jumper to select any one of these transmit-timing sources:
• Recovered clock from the received pair;
• External timing from the data-communication (DTE) interface; or
• Internal timing (used only for testing and diagnostics).
Two internal 16-bit buffers accommodate the difference in clocking phase.

12
G.703 CODIRECTIONAL CONVERTER
Figure 2-1 below shows a typical application of the G.703 Codirectional
Converter.
Figure 2-1. Typical G.703 Codirectional Converter application.
The Converter can act as a data-rate adapter, allowing you to connect DTEs
running at 48 or 56 kbps to a 64-kbps G.703-interface line. At 48 or 56 kbps,
depending on what you do or don’t connect to the Converters’ Request to
Send and Carrier Detect leads, you can use the extra bandwidth in any of
these ways:
• Nothing connected to Converter RTS (56 kbps only): To guarantee the
satisfaction of the “ones density” requirement, by placing a “1” after every
seven bits.
• Devices’ RTS connected to Converters’ RTS, and DCD to DCD: To pass a
control signal (RTS/DCD) end-to-end.
• Async devices’ Transmit Data to Converters’ RTS, and Receive Data to
CTS: As a 1200-bps asynchronous secondary channel for connecting
additional DTE units over the same link.
You can use the Converter’s front-panel LEDs to continuously monitor the
main channel’s activity and synchronization.
The Converter provides V.54 diagnostic capabilities with local digital and
analog and remote digital loopbacks. All three loops can be activated by
pressing front-panel pushbuttons; the latter two can be activated by raising
the appropriate interface signal from the local DTE.
Another of the front-panel pushbuttons triggers an internal 511-bit pseudo-
random V.52 test pattern for direct end-to-end integrity testing. The ERR LED
flashes for each each error detected.
G.703
Codirectional
Converter
DTE
48, 56, or
64 kbps T1 or E1
Network
V.35, V.36 (RS-449/422),
X.21, or RS-530 Cable
G.703 Codirectional
Line, 64 kbps
Office-
side PCM
equipment

13
CHAPTER 2: Introduction
2.2 Timing Theory
2.2.1 CCITT G.703 S IGNALING
The CCITT G.703 codirectional signal is made up of two balanced signals:
The receive and transmit signals carry timing and data information.
The clock signal associated with each direction of transmission travels in the
same direction as the data signal (see Figure 2-2 below).
Figure 2-2. G.703 Codirectional Converter signaling.
2.2.2 G.703 C ODIRECTIONAL T IMING
The G.703 Codirectional Converter can support virtually all timing options
that you might need, as described and illustrated in this section.
G.703 Receive Timing Used for G.703 Transmit Timing
When G.703 receive timing is used for G.703 transmit timing, three timing
options for the data-communication side, associated with the loopback timing
(LBT) on the G.703 side, are available:
• Receive Clock and Transmit Clock are both outputs from the Converter,
which serves as a DCE (see Figure 2-3 on the next page).
• X.21 interface only: Receive Clock and Transmit Clock are both inputs to
the Converter, which serves as a DTE (see Figure 2-4 on the next page).
• Receive Clock is an output from the Converter, while Transmit Clock is an
input to the Converter from an external DCE, for connection to a tail
circuit (see Figure 2-5 on page 15).
Information Signal
Timing Signal
PCM
Equip.
DCE
(Modem, Mux, etc.)
async (PC,
Term., etc.)
DTE,
G.703
Codirectional
Converter

14
G.703 CODIRECTIONAL CONVERTER
Figure 2-3. LBT-DTE Connection.
Figure 2-4. LBT-DCE21 Connection.
Information Signal
Timing Signal
Information Signal
Timing Signal
G.703 Codirectional
Converter
Elastic
Buffer
Elastic
Buffer
DCE
PCM
Equip.
Elastic
Buffer
Elastic
Buffer
G.703 Codirectional
Converter
DCE
PCM
Equip.

15
CHAPTER 2: Introduction
Figure 2-5. LBT-DCE Connection.
Transmit-Clock Timing Mode
When you use the external transmit clock on the data-communications side
for G.703 transmit timing, there is complete independence, within the G.703
Codirectional Converter, between the receive and the transmit directions of
transmission. Figure 2-6 on the next page shows this timing mode.
Internal-Clock Timing Mode
The Converter’s internal oscillator is usually used as the source for G.703
transmit timing for testing purposes only, but can also be used with systems
that do not have a clock source. Figure 2-7 on the next page shows this timing
mode.
Information Signal
Timing Signal
Elastic
Buffer
Elastic
Buffer
G.703 Codirectional
Converter
DCE
PCM
Equip.

16
G.703 CODIRECTIONAL CONVERTER
Figure 2-6. Transmit-Clock Timing Mode.
Figure 2-7. Internal-Clock Timing Mode.
Information Signal
Timing Signal
Information Signal
Timing Signal
DCE
G.703 Codirectional
Converter
PCM
Equip.
Elastic
Buffer
Elastic
Buffer
G.703 Codirectional
Converter
DTE or DCE
PCM
Equip.
Elastic
Buffer
Elastic
Buffer
Oscillator

17
CHAPTER 2: Introduction
2.2.3 T AIL
-E ND C LOCKING
Transmit clock from the external DCE source is provided for applications
requiring the use of a modem in order to reach a remote DTE, as shown in
Figure 2-8 on the next page (see Figures A-2, A-7, and A-10 in the Appendix
for pinouts). Use the LBT-DCE-timing mode with the G.703 Codirectional
Converter (see Figure 2-5 on page 15).
2.2.4 G.703 C ODIRECTIONAL R ULES
G.703 codirectional signals, in each direction of transmission, are coded as
follows: The composite timing/ data signal conveys the 64-KHz bit-timing
information, the 8-KHz octet information (by introducing violations into the
signal), and the 64-kbps data pattern.
• A binary one (64-kbps bit period) is coded as a block of the four bits
“1100.”
• A binary zero (64-kbps bit period) is coded as a block of the four bits
“1010.”
The binary signal is converted into a three-level signal by alternating the
polarity of the blocks. The alternation of the polarity of the blocks is violated
every eight blocks (see Figure 2-9 on the next page).

18
G.703 CODIRECTIONAL CONVERTER
Figure 2-8. Tail-Circuit Application.
Figure 2-9. G.703 Code Conversion.
6 7 8 1 2 3 4 5 6 7 8 1
0 0 0 1 1 0 1 0 1 1 1 0
G.703 Codirectional
Converter
G.703 Line
Tail-End Circuit
TC
TD
RD
RC
TD
EXTC
EXTC
RD
RC
Modem
(V.35, V.36, RS-530)
Modem Line Side of
Office
Terminal
Bit Number
64-kbps data
Binary Data
Three-Level Data
Violated Data

19
CHAPTER 2: Introduction
2.3 Rate-Conversion Rules
56-to-64-kbps conversion is performed by suppressing bit position number 8.
This bit position coincides with the introduced violation (as shown in Figure
2-9), and thus suppressing it conforms to the requirements of ITU-TSS
(CCITT) standard V.110 for 56- to 64-kbps rate conversion. The suppressed
bit can be used for RTS-DCD end-to-end signalling or for a secondary async
channel. North American T1 (1.544-Mbps) applications require that this bit
position be set to a binary “1.” You can do this easily by leaving the RTS pin
open (not connected).
48-to-64-kbps conversion is performed by suppressing bit positions number 7
and 8. The suppressed bits are used in the same way as those suppressed for
56-to-64-kbps conversion.
2.4 Physical Description
The G.703 Codirectional Converter is a standalone unit. The unit is designed
for installation on top of a bench or a shelf, but can also be mounted on a 19-
inch rack with the proper adapter kit. One or two standalone units can be
installed together.