gateway 2m 2w v5

Configuration of modems for user’s record

Configuration of Gateway 2M/2W modem with G.703/V.35 Interface

Serial No. : _________________________

Operating Mode : Central / Remote

Data Rate : _____________________Kbps

Clock Mode : _________________________

If G.703 modem

PCM Mode : Unframed / PCM31 / PCM30

Starting Time Slot : _________________________

CRC-4 : ON / OFF

E1 Line Type : Short / Long Haul

If V.35 modem

TX Clock Polarity : Normal / Inverted

RX Clock Polarity : Normal / Inverted

Manual Release Note

This manual is to be used for Gateway 2M/2W version V501. The version is marked on

the product label pasted under the product. It is mentioned next to the Product Name,

e.g. Gateway 2M/2W/V.35 (V501).

For earlier or later version, different manual versions are available. Please contact

Technical Support (see Chapter 5 for Technical Support details).

Versions Reference User’s Manual Remarks

V501 and onwards

Release No. : GW-2M/V6.0.2/2K7 Released on : May 2007

Improved design/look

V501 and onwards

Release No. : GW-2M/V6.0.1/2K6 Released on : June 2006

Compact size, Long haul/Short haul option added for G.703 modem

V408 and V409 Release No. : GW-2M/V5.0.2/2K5 Released on : November 2005

Rear Panel improved, BNC on G.703 made optional

V406 and V407 Release No. : GW-2M/V5.0.1/2K5 Released on : July 2005

Different clocking options added.

V401 to V405 Release No. : GW-2M/V5.0.0/2K5 Released on : January 2005

TABLE OF CONTENTS Chapter 1 - Introduction ........................................................................................... 1

1.1 Features ................................................................................................. 2

1.2 Typical Applications ................................................................................ 3

1.2.1 Extending G.703/E1 interface to Customer premises ....................................... 3

1.2.2 Carrying data within an exchange or campus ................................................... 3

1.2.3 Carrying voice within an exchange or campus .................................................. 4

1.2.4 Carrying data through different exchange areas ............................................... 4

1.3 General Overview ................................................................................... 5

Chapter 2 - Functional Description ......................................................................... 7

2.1 Functional Overview ............................................................................... 7

2.1.1 Application Interface .......................................................................................... 7

2.1.2 Digital Signal Processing ................................................................................... 8

2.1.3 Analog Front End ............................................................................................... 9

2.2 System Implementation .......................................................................... 9

2.2.1 Main Board ......................................................................................................... 9

2.2.2 Interface Board ................................................................................................ 10

2.2.3 DSL Board ....................................................................................................... 10

Chapter 3 - Installation & Configuration ............................................................... 11

3.1 Unpacking ............................................................................................. 11

3.2 Safety Requirements ............................................................................ 11

3.3 Site Selection ........................................................................................ 11

3.4 Cable Pair Qualification Requirement ................................................... 12

3.5 Installation ............................................................................................. 14

3.6 Making Power Connection .................................................................... 15

3.7 Earthing ................................................................................................ 16

3.8 Making Line Connection ....................................................................... 17

3.9 Connecting the DTE............................................................................... 18

3.9.1 Connecting G.703 Interface.............................................................................. 18

3.9.2 Connecting V.35 Interface ................................................................................ 18

3.10 Configurations ....................................................................................... 19

3.10.1 Default Configuration of Gateway 2M/2W with G.703 Interface...................... 19

3.10.2 Default Configuration of Gateway 2M/2W with V.35 Interface ........................ 19

3.11 Clock Modes and Applications .............................................................. 27

3.11.1 Transmit and Receive Clock details in different Clock Modes ........................ 28

3.12 LED Indicators ...................................................................................... 29

Chapter 4 - Maintenance & Troubleshooting ....................................................... 31

4.1 How to measure the Quality of Copper Cable........................................ 31

4.1.1 Console Port Setup .......................................................................................... 31

4.1.2 Monitor through Console Port .......................................................................... 32

4.2 Diagnostic Tests ................................................................................... 33

4.2.1 Local Loopback Test ........................................................................................ 33

4.2.2 Digital Loopback Test ...................................................................................... 34

4.2.3 Remote Loopback Test .................................................................................... 35

4.2.4 Bit Error Rate Test ........................................................................................... 36

4.2.5 System Reset ................................................................................................... 36

Chapter 5 - Technical Support & Warranty ........................................................... 38

5.1 Technical Support Sheet ...................................................................... 38

5.2 Nomus Comm-Systems Limited Warranty ............................................ 39

Appendix A Technical Specifications ................................................................. 40

Appendix B V.35 Interface .................................................................................. 41

Appendix C RS-530 Interface ............................................................................. 42

Appendix D G.703 Interface ................................................................................ 43

Appendix E Line Interface .................................................................................. 44

Appendix F MMS Cable Details .......................................................................... 45

TEC Approval Certificate ....................................................................................... 46

LIST OF FIGURES Figure 1.0 Gateway 2M/2W Modem .......................................................... 1

Figure 1.2.1 Application Example-1.............................................................. 3




Figure 2.1 Gateway 2M/2W Functional Block Diagram ............................. 7

Figure 3.5.1 Gateway 2M/2W/G.703 Rear Panel ....................................... 14

Figure 3.5.2 Gateway 2M/2W/V.35 Rear Panel.......................................... 15

Figure 3.7 Loop connector JPP Location on Modem Board ................... 17

Figure 3.12 Gateway 2M/2W Front Panel ................................................. 29

Figure 4.2.1 Local Loopback ..................................................................... 33

Figure 4.2.2 Digital Loopback .................................................................... 34

Figure 4.2.3 Remote Loopback ................................................................. 35

LIST OF TABLES Table 3.4.1 Loop Resistance/Distance supported ..................................... 12

Table 3.10.1 Summary of DIP Switch Configuration for Gateway 2M/2W ... 21

Table 3.10.2 Master/Slave Selection........................................................... 22

Table 3.10.3 PCM 30/31 Selection.............................................................. 22

Table 3.10.4 CRC Generation ..................................................................... 22

Table 3.10.5A Data Rate Selection for G.703 modem................................... 23

Table 3.10.5B Data Rate Selection for V.35 modem ..................................... 24

Table 3.10.6 Starting Time Slot Selection ................................................... 25

Table 3.10.7 Transmit & Receive Clock Polarity Selection.......................... 26

Table 3.10.8 Clock Mode Selection............................................................. 26

Table 3.10.9 Short Haul / Long Haul Operation .......................................... 26

Table 3.11.1 Clock Modes for E1 – E1 Application .................................... 27

Table 3.11.2 Clock Modes for E1 – V.35 Application ................................. 27

Table 3.11.3 Clock Modes for V.35 – V.35 Application ............................... 27

Table 4.1.1 Distance/Loop Resistance vs ATT & NMR ............................ 32

Table 4.2.1 Trouble Shooting ................................................................... 37

Gateway i 2M/2W User Manual Page – 1

Chapter 1 - Introduction

The Nomus Gateway 2M/2W modem utilizes G.SHDSL technology, as per ITU G.991.2

combining the best of TC-PAM, SDSL and HDSL2 to achieve a faster and more

efficient data transmission, over a 2-wire copper cable. It uses G.SHDSL TC-PAM, G.h.

Protocol technology to automatically negotiate the most optimum speed as per the

distance and quality of the Digital Subscriber Line (DSL). The distance or range can be

increased by lowering the line rate. The minimum line rate is 192Kbps.

The Nomus Gateway 2M/2W modem is used to carry up to 2048 Kbps of Voice traffic in

G.703 E1 format or Data in V.35 or G.703 format to a distance of over 6.0 Km on a 2-

wire 24 AWG (0.5mm) copper cable. It can be used by ISPs, Corporations and

Telephone Companies, etc. to provide high-speed data communication for Internet or

Intranet Access, Frame Relay, ATM, etc.

Figure 1.0 - Gateway 2M/2W Modem

The Gateway 2M/2W offers 2 digital interfaces: V.35/RS530/X.21 or G.703. The

Gateway 2M/2W modem with V.35 interface supports synchronous data rates of n x 64

Kbps from 64Kbps to 2304Kbps. The Gateway 2M/2W modem with G.703 interface

supports data from 64Kbps to 2048Kbps.


1.1 Features

G.SHDSL (G.992.1) Standard with TC-PAM coding

2 -Wire Leased Line operation.

Data Rates of nx64Kbps (n=1 to 36), 64Kbps up to 2304Kbps.

Range of 6.0 Km on a 2-wire over 24 AWG (0.5mm) twisted cable pair for

2048Kbps. Longer distances of over 10 Kms can be obtain for lower line

rates and speeds.

Supports V.35/RS530/X.21 or E1/G.703 interfaces.

Supports 120 Ohms Balanced (RJ45) or optional 75 Ohms Unbalanced

(BNC) G.703 interfaces.

Framed/Unframed PCM 30/PCM 31 E1 signal on G.703 interface.

Selectable Short haul or Long haul operation for G.703 interface.

Embedded Channel for Control and Supervision.

Supports Internal, External and Received Clock options for the Transmit

Clock source.

SNMP compliant MMS port for Modem Management (optional).

Local, Digital and Remote Loopbacks.

In-built Test Pattern generation and detection.

Extremely simple installation procedure.

Provides built-in protection against Line Surges.

Complies with ITU-T K.20, K.21.

AC and DC Switched Mode Dual Power Supply for G.703 modem.

Rugged Aluminium Casing.

Compact Front-Panel with Diagnostic Keys and 10 LEDs for Status

Information.

Convenient DIP Switches for different configurations of Speeds, etc.


1.2 Typical Applications

1.2.1 Extending G.703/E1 interface to Customer premises

Two Gateway 2M/2W modems with G.703 interface are used to extend the E1 interface

from the exchange to the RAS equipment at the customer premises as shown in Figure

1.2.1.

Figure 1.2.1 - Application Example-1

1.2.2 Carrying data within an exchange or campus

Two Gateway 2M/2W modems with V.35 interface are used to transport data between

two subscriber premises, which are located in the same exchange area or within a

campus as shown in Figure 1.2.2.



1.2.3 Carrying voice within an exchange or campus

Two Gateway 2M/2W modems with G.703 interface are used to carry voice between

two subscriber premises, which are located in the same exchange area or within a

campus as shown in Figure 1.2.3.


1.2.4 Carrying data through different exchange areas

In case the subscribers are located in different exchange areas, a pair of Gateway

2M/2W modems with V.35 and G.703 interfaces is used to transport data between each

subscriber and exchange as shown in Figure 1.2.4.



1.3 General Overview

The Gateway 2M/2W employs adaptive Equalization & Filtering, Echo-Cancellation and

other DSP techniques to compensate for varying line conditions, noise & cross-talk and

provide error-free, reliable connectivity. An embedded channel, which does not interfere

with the data, provides setup, monitoring and diagnostics features.

The Gateway 2M/2W/V.35 modem, transmit clock is either generated internally,

recovered from DSL or received from the DTE as External Clock to transmit data on the

DSL line.

The Gateway 2M/2W/G.703 can operate from G.703 Recovered or internal transmit

clock source.

The Gateway 2M/2W modem has a convenient Front Panel with 10 LEDs for

comprehensive status indication, besides Switches for loopback tests. An embedded

channel, which does not interfere with the data, provides setup, monitoring and

diagnostics features. Analog, Local/Remote Digital loopbacks and Test Pattern

generation & checking provide the means for trouble-shooting the lines as well as the

local and remote modems.

The modem operating parameters are determined by two DIP switches located at the

bottom of the modem. Refer Chapter 3, Installation and Configuration, for more details

of operating parameters and its configuration.

An MMS port is provided for comprehensive Modem management from a PC or an

SNMP compliant system and also to provide Alarm Indications.


Performance and Reliability are the hallmarks of all Nomus products and these

products are no exceptions. They provide high immunity to background noise on

Telecom Service Providers Copper infrastructure allowing multiple Data channels on

the same physical cable. They have extra protection for power fluctuations (Switch

Mode Power Supply – SMPS) and telephone line surges (Sidactors and Poly Fuses). It

can thus meet the tough demands of the Indian environment and user are assured of

reliability, productivity, quality and value.


Chapter 2 – Functional Description

2.1 Functional Overview

The Nomus Gateway 2M/2W functions can be split into three functional blocks:

• Application Interface

• Digital Signal Processing (DSP)

• Analog Front End (AFE)

Figure 2.1 - Gateway 2M/2W Functional Block Diagram

2.1.1 Application Interface

There are two types of Application Interfaces available at present. They are

• E1 Interface supports both Framed and Unframed data

• V.35 Interface supports Nx64Kbps data rates where N = 1…36

2.1.1.1 E1/G.703 Interface:

G.703/E1 interface is a 4-wire physical interface where one pair is for transmitting the

data and the other pair is for receiving the data. HDB3 line code is being used which is

as specified by ITU-T. E1 interface is responsible for providing the necessary framing

information. The G703/E1 interface extracts both the clock and data from incoming

stream. Alternatively, it can operate with internally generated timing also. The E1 frame

consists of 32-code words called timeslots and are numbered 0 through 31. A PCM31

frame comprises of 31 timeslots used for traffic and 1 timeslot used for synchronization.

A PCM30 frame comprises of 30 timeslots used for traffic and 2 timeslots used for

synchronization and signaling processes. Unframed data is a 2048Kbps data stream, in

which case, there is no framing information available. The G703/E1 Interface supports

both Balanced (120 Ohms) and Unbalanced (75 Ohms) modes.


2.1.1.2 V.35 Interface:

The V.35 interface is a serial synchronous interface, which will be operated in DCE

modes. This interface operates in Internal, Recovered or External clock modes at

Nx64Kbps rates. The Maximum data rate is 2304Kbps.

2.1.2 Digital Signal Processing (DSP)

The DSL framer provides clock, data, and frame conversion from various PCM frame

formats to various DSL applications. The DSL framer provides full PCM termination

capabilities, including synchronization and management of E1 PRA. The DSL rate can

vary from 192Kbps to 2.304Mbps (E1 + overhead).

The transmitter receives a bit streams from the DSL framer and maps the data bits to

the appropriate Pulse Amplitude Modulation (PAM) symbols. An optional Tomlinson-

Harashima precoder (THP) follows the PAM mapper. The signal is then processed by

the transmit filter to achieve the desired time and/or frequency domain characteristics

before being forwarded to the Analog Front End (AFE).

The receiver receives serialized data from the AFE device and from precoded symbols

from the bit pump transmitter. The precoded symbols feed into an Echo Canceller (EC)

that estimates the echo response and subtracts it from the AFE samples. The signal is

equalized using a Feed Forward Equalizer (FFE) and a Decision Feedback Equalizer

(DFE) finally; a Trellis Coded Modulation (TCM) decoder recovers the information bits.

An error predictor is used as a part of the startup algorithm and as a precoder

coefficient adaptation machine during normal operation.

The G.hs block implements the G.994.1 handshaking function. The handshaking

function provides a flexible mechanism for DSL transceivers to communicate before

exchanging signals that are specific to a particular DSL recommendation or standard.

The G.994.1 standard defines the signals, messages, and procedures for exchanging

information about the capabilities of each transceiver and for selecting common modes

of operation.


DSP includes a built in Bit-Pump with transmitter and receiver section, Echo Canceller,

Trellis Coded Modulation (TCM) decoder, Equalizer etc.

2.1.3 Analog Front End (AFE)

The AFE performs the analog functions required for transmission and reception of

G.shdsl signals. It includes the Digital-to-Analog (D/A) and Analog-to-Digital (A/D) data

converters, anti-aliasing and post filtering circuitry, gain control blocks, and line drivers.

AFE serial digital interface connects to the DSL Framer. The serial interface protocol is

proprietary. The DSP transceiver indirectly controls the AFE. The AFE interface

consists of the line driver, impedance-matching resistors, external hybrid, and

transformer.

2.2 System Implementation

The blocks described above figure 2.1 have been implemented in the Gateway 2M/2W

as two boards:

• Main board

• Interface Board (E1 interface board/V.35 interface board)

• DSL Daughter Board

2.2.1 Main Board

The Main Boards consists of the Microcontroller and its peripherals. It provides for the

following Add-On Slots:

• Digital Interface

• DSL Slot

It also provides the NMS and the DSL connectors.

The Micro controller does phase acquisition and certain startup procedures for

operation of the DSP. It collects information on EOC of the xDSL signal from the

Framer. It implements the NMS operation and estimates the BER from known pattern


transmitted by Slave (or Master). The LED display status, Sync fail and restart

operations are also controlled by the Micro controller.

The Line protection circuitry is also present on the Main Board. The circuit protects the

equipment components from Lightning and other Voltage surges.

2.2.2 Interface board

This board is either the G.703 Framer board in the Gateway 2M/2W/G.703 or the V.35

Data Board in the Gateway 2M/2W/V.35.

2.2.2.1 G.703 Framer Board:

This board is responsible for the complete G.703 interface according to the ITU

standards. It performs transmit pulse shaping and receive equalization and clock

recovery. Transmit clock can be as recovered from the G.703 interface or internally

generated .The G.703 board also performs E1 framing on the transmit direction and

synchronizes to received E1 frames in the receive direction. The data is then

exchanged between the G.703 interface and the DSL interface. It supports framing as

per G.704 as well as CRC generation.

2.2.2.2 V.35 Data Board:

This board provides all the electrical signals as required for Nx64Kbps (where N=1...36)

data operation on V.35. Transmit clock can be generated internally or recovered from

DSL framer or DTE provided clock. The received clock is recovered from the DSL

framer. This board performs the necessary buffering between the V.35 Nx64 interface

and the DSL interface. It also performs diagnostics such as Test Pattern generation and

checking.

2.2.3 DSL Board

The DSL board consists of the DSL Framer, AFE and the Line interface with Hybrid.

The Data interchanged between the two DSL units is provided to the Digital Interface

from this board.


Chapter 3 – Installation & Configuration

3.1 Unpacking

Check for accessories as per the checklist pasted on the modem packing box. Do not

dispose the box in case user need to store the modem or ship it in the future. The box

should contain the following items.

• Gateway 2M/2W Modem (with V.35 or G.703 interface )

• Cables:

a. 1 No. RJ 45 “GW 2M LINE” DSL line cable

b. 1 No. RJ 45 “GW 2M G.703” RX/TX cable for G.703 interface

modem only

• Power Cord (AC & DC both for Dual power G.703 interface modem)

• User Manual CD.

3.2 Safety Requirements

The circuit boards used in the modems consist of the components that have a low

current consumption. On the other hand they are extremely sensitive to the electrostatic

discharge and should be handled with care. To prevent damage to the electronics

components of the modem, it is advisable to ensure an optimal electrical contact

between yourself, the working area and a safety ground before touching any circuit

board. Take special care not to touch any component or connector on the circuit board.

Do not open the modem unless absolutely necessary.

3.3 Site Selection

Though the modems function in a temperature range of 0°C to +50°C and in humidity

upto 95%, a location should be preferably chosen as follows:

• Install the modem in an area free of extreme temperatures, humidity,

shock and vibration. Operation at low temperature prolongs the service

life and MTBF.


• Always place the modem on its feet without blocking the air vents of the

modem. Do not stack multiple units directly onto each other, as stacking

can cause heat build-up that could damage the equipment.

• Do not place it near other equipment that can emit strong electromagnetic

radiation, e.g. Transformers, power rectifiers etc.

• Position it so that user can easily see and access the front panel and its

control indicators. Leave enough clearance at the back for cables and

wires.

3.4 Cable Pair Qualification Requirement

The following precautions may be taken in selection of copper pair before installing the

modems.

• Loop Resistance/Distance supported: Check the continuity of the copper

cable pair using multi meter by looping one end of the pair. Also measure

the Loop Resistance. The Loop Resistance of 1Km cable pair is

approximately 172 Ohms. For example, if the distance between the

modems is 3Km then the loop resistance should be approximately 3x172

= 516 Ohms. The maximum Loop Resistance and Distance between

Central and Remote modems using a 0.5mm cable shall not exceed the

limit specified as listed in the table below.

Table 3.4.1 – Loop Resistance/Distance Supported

Sr. No. Data Rate Distance Loop Resistance

1 2048 Kbps 6 Km 1032 Ohms

2 1024 Kbps 7.2 Km 1240 Ohms

3 512 Kbps 8.5 Km 1470 Ohms

4 192 Kbps 10.2 Km 1760 Ohms

If the Loop Resistance is higher than the specified limit, then the modems

will not connect. If the Loop Resistance is within the specified limit and


modems still do not connect or there are data errors then the copper pair

may be having other problems as listed below. Refer Section 4.1 for

details on how to measure the quality of the copper pair. User will need a

PC and a connecting cable.

• Voltages on DSL Line: There shall not be any AC or DC voltages across

the line, measured using a multi meter. There shall not be any voltage to

Earth from any of the line limbs. This should be confirmed with a Megger.

• Crosstalk: In a multi-pair cable bundle, make sure that the wires of cable

pairs are not inter-changed, i.e. wire A of Pair 1 is not connected to wire B

of Pair 2 and vice versa. This will result in crosstalk and data errors.

• Open Joints: There should not be any open joints in the cable pair as they

carry high frequency signals. Ensure that the joints are proper and cover

the open joints with insulation tape.

• Bridged Taps: There should not be any long Bridged Taps. Bridge Taps

are unused pairs connected in parallel to the twisted pairs being used.


3.5 Installation

Warning!

Keep the equipment powered off during the installation process.

The rear panel of the Gateway 2M/2W consists of the following:

1. Power On/Off Switch

2. IEC type Power Connector and Fuse Holder

3. Interface in the form of

An RJ45 Connector for 120 Ohms Balanced G.703 Interface and

Optional 2 nos. BNC connectors (RX and TX) for 75 Ohms Unbalanced

G.703 Interface.

Or

A 34-Pin female V.35 connector or 25-Pin female D-type RS530

Connector.

4. An RJ45 Connector for MMS - Modem Management (Optional)

5. An RJ45 Connector (RJ1) for DSL LINE connection.

6. An External Protective Earth Terminal ‘PE’ for proper Earth connection, if

required.

Figure 3.5.1 - Gateway 2M/2W G.703 Rear Panel


Figure 3.5.2 - Gateway 2M/2W V.35 Rear Panel

3.6 Making Power Connection

The Gateway 2M/2W modems are factory fitted with Dual Power Supply that can work

with both 230 VAC and 48 VDC. Only the power cord has to be changed as per the

input. Both types of power cords are provided with the 2M/2W/G.703 modem.

AC power: Plug the power connector into an AC outlet having a voltage rating between

180 – 240 VAC with a minimum of 5A load capacity. Position the modem within 2m of a

power outlet.

DC power: Connect the modem to a DC power source as described below. The Power

cable for –48V DC is terminated on a three-pin tag block connector.

1. Connect the Earth to the green wire on the tag block.

2. Connect the +48VDC source to the Red wire on the tag block.

3. Connect the -48VDC source to the Black wire on the tag block.

4. DC power cable length should not exceed 15 meters of length from the

power source.


3.7 Earthing

In order to meet the international EMC requirements and standards for line protection

like ITU-T K.20, K.21, before switching on the modem and connecting or disconnecting

any other cable, the protective ground conductor of the mains (AC or DC) power cord

must be properly connected to Earth. The voltage between Earth and Neutral on AC

cord must be less than 2 VAC. If user is using an extension cord (power cable) make

sure it is grounded as well.

The Gateway 2M/2W uses multi-stage line protection circuit. A hybrid fast response

protection device is used in conjunction with Earth to divert high energy to Earth during

ESD and lightning strikes. But poor Earthing may cause data errors at higher line

speeds. So Gateway 2M/2W provides the options of using either the Power Earth or

External Earth.

By default, the Gateway 2M/2W uses the Earth from user’s power connection for the

protective Earth as well. Alternately, it has an External Protective Earth terminal ‘PE’

which can be used in circumstance where the Power Earth is not available or where the

Infrastructure provides a good External Earthing.

To use the External Earthing remove the Loop Connector JPP provided inside the

modem on the board (PCB), as shown in the Fig 3.7 below. Connect the Protective

Earth Terminal, located on the rear panel of the modem, to a known good External

Earth with a strap (not provided with the modem).

Where there is no provision for proper Power Earth or External Protective Earth, the

Modem Performance may be affected with occasional bursts of Errors. In such a

situation, the user may Open the Loop Connector JPP to improve the performance and

reduce errors. However, this will compromise the safety of the equipment and Nomus

strongly recommends that proper Earthing be provided through the Power Socket or a

good External Protective Earth Terminal.


Fig 3.7 - Loop connector JPP location on Modem board (PCB)

Warning!

While opening the Top cover of the modem to open or close the JPP loop connector,

make sure the EE link of the Protection Earth Terminal is not removed accidentally

from the modem board. And it is connected back properly, if removed while opening

the Top cover of the modem.

3.8 Making Line Connection

Place the modem at a location close to the line termination.

An RJ45 socket marked DSL LINE is used for the line connection. For making the line

connection the RJ45 cable is provided with RJ45 jack on one end and terminal strips at

the other end marked with LINE. Connect the line to the terminal strip marked with LINE

and connect the other end of the same cable to the RJ1-DSL LINE socket on the rear

panel of the modem. Also refer Annex-E for more details.


3.9 Connecting the DTE

3.9.1 Connecting G.703 Interface

120 Ohm Balanced termination on RJ45

An RJ45 cable is provided with an RJ45 jack on one end and terminal strip at

the other end which is marked with TX and RX. Insert the RJ45 jack in to

RJ45 connector marked G.703 on the rear panel and connect the 4 wires

from the PCM/E1 to the terminal strip appropriately and make sure the

connection is reliable. The Orange & Orange white wires are TX and Green &

Green white wires are RX. Also refer Annex-D for more details

Co-axial 75 ohm termination on BNC (Optional)

2 BNC connectors marked TX and RX are provided for the 75-Ohm

unbalanced G.703 interface to connect the PCM/E1 on the rear panel of the

modem. Use co-axial cables (not provided) to connect to similar BNC

connectors of the PCM/E1 card.

3.9.2 Connecting V.35 (or RS530) Interface

In the Gateway 2M/2W, connect the V.35 (or optionally RS530/X.21) Cable (not

provided) from the DTE to the Digital Connector provided at the rear of the Gateway

2M/2W. Refer Annex-B for V.35 Interface (Annex-C for RS530) connector details.

Tighten the support screws to make a reliable connection.


3.10 Configurations

The Gateway 2M/2W with G.703 or V.35 interface is pre-configured as following.

3.10.1 Default Configuration of Gateway 2M/2W with G.703 Interface

Modem Operating Mode : Central

Number Of Pairs : Single Pair

Interface Type : E1

E1 Line Type : Short Haul

Local IF Data Rate : 32x64 (2048) Kbps

Starting Time Slot : 0

PCM Mode : Unframed

CRC-4 : Not Applicable

Clock Mode : Plesio Synchronous – External

3.10.2 Default Configuration of Gateway 2M/2W with V.35 Interface

Modem Operating Mode : Remote

Number Of Pairs : Single Pair

Interface Type : V.35

Local IF Data Rate : 32x64 (2048) Kbps

Starting Time Slot : Not Applicable

TX Clock Polarity : Normal

RX Clock Polarity : Normal

Clock Mode : Synchronous – Internal


The user can change the above default configuration of Gateway 2M/2W as per

requirement or application of customer. Two 8 position DIP Switches, SW1 and SW2

are located on the bottom surface of the modem for configuration of modes and

speeds.

1. In a pair of modems, configure one modem as Remote by turning ON DIP

Switch SW1-1 and other as Central by keeping that switch OFF (Table

3.10.2). Typically, the modem situated at the Exchange or ISP premises is

configured as Central.

2. Bi-Directional External, Uni-Directional External or Uni-Directional Internal

clock mode can be selected with DIP Switch SW2-7 & 8 as per Table

3.10.8. By default, Uni-Directional Internal Clock is selected in V.35

modem (SW2-7 is OFF and SW2-8 is ON) and Bi-Directional External

Clock is selected in G.703 modem (SW2-7 is ON and SW2-8 is OFF).

3. The DIP switches SW1-4,5,6,7,8 are used for Data Rate (n x 64 Kbps)

selection for the modem with G.703 interface as per Table 3.10.5A. If the

modem is with V.35 interface, the DIP switches SW1-4,5,6,7,8 and SW2-1

are used for Data Rate (n x 64 Kbps) selection as per Table 3.10.5B. By

default, 2,048 Kbps (2 Mbps) operation is selected.

4. In Framed mode, Switches SW2-1,2,3,4,5 are used for the Starting Time

Slot selection as per Table 3.10.6. In Framed mode, Time Slot 0 is used

for Sync information. Data can start from Time Slot 1 or any later Time

Slot there after. When an N value of 32 is selected, the interface operates

in Unframed mode. Invalid Time Slot selection causes the 4 Red FP LEDs

to blink at Power On. By default these Switches are OFF as default

configuration is Unframed, 2048Kbps.

5. In Framed mode, SW1-2 is used to select PCM 30 or 31 as per Table

3.10.3. In PCM 30 mode, the Time Slot 16 is ignored. By default the

modem is set for Unframed and this Switch is OFF.

6. In a G.703 modem, in Framed mode, Switch SW1-3 is used to enable or

disable CRC generation as per Table 3.10.4. There is no significance of

CRC in Unframed mode and this Switch is OFF by default.


7. In a G.703 modem, Switch SW2-6 is used for selection of Short haul or

Long haul operation as per Table 3.10.9. Short haul operation is selected

if the distance between modem and the PCM Mux is less than 200mtr.

Long haul operation is selected if the distance between modem and the

PCM Mux is more than 200mtr. By default, this SW 2-6 is OFF selecting

Short haul operation.

8. In a V.35 modem, user can select different clock polarities for Transmit

and Receive Clocks, so that the modem can be compatible with various

makes of Routers and Multiplexers. SW2-4,5 are used for different

Receive and Transmit clock polarity selection as per Table 3.10.7. By

default these Switches are OFF.

Table 3.10.1 - Summary of DIP Switch Configuration for Gateway 2M/2W

DIP SWITCH V.35 E1/G.703

SW1-1 Central or Remote selection

SW1-2 Reserved PCM 30/PCM31

SW1-3 Reserved CRC ON/OFF

SW1-4

SW1-5

SW1-6

SW1-7

SW1-8

Nx64 Kbps speed selection

(N=1,…32)

SW2-1

Nx64 Kbps speed selection

(N=1,...36)

SW2-2 Reserved

SW2-3 Reserved

SW2-4 TX Clock polarity selection

SW2-5 RX Clock polarity selection

Starting Time Slot selection

SW2-6 Reserved Short Haul/Long Haul Operation

SW2-7 TX Clock source selection

SW2-8 Uni-directional / Bi-directional Mode


Table 3.10.2 - Master/Slave Selection

SW1-1 Function

OFF Selects Central (Master) Mode

ON Selects Remote (Slave) Mode

Table 3.10.3 – PCM 30/31 Selection (Applicable for Gateway 2M/2W G.703 only)

SW1-2 PCM 30/31 Selection

OFF PCM 31 (Default)

ON PCM 30

Table 3.10.4 – CRC Generation (Applicable for Gateway 2M/2W G.703 only)

SW1-3 CRC Generation

OFF Disables CRC Generation (Default)

ON Enables CRC Generation


Table 3.10.5A – Data Rate Selection (for G.703 modem only)

SW1-8 SW1-7 SW1-6 SW1-5 SW1-4 n Data Rate Kbps

ON ON ON ON ON 1 64

ON ON ON ON OFF 2 128

ON ON ON OFF ON 3 192

ON ON ON OFF OFF 4 256

ON ON OFF ON ON 5 320

ON ON OFF ON OFF 6 384

ON ON OFF OFF ON 7 448

ON ON OFF OFF OFF 8 512

ON OFF ON ON ON 9 576

ON OFF ON ON OFF 10 640

ON OFF ON OFF ON 11 704

ON OFF ON OFF OFF 12 768

ON OFF OFF ON ON 13 832

ON OFF OFF ON OFF 14 896

ON OFF OFF OFF ON 15 960

ON OFF OFF OFF OFF 16 1024

OFF ON ON ON ON 17 1088

OFF ON ON ON OFF 18 1152

OFF ON ON OFF ON 19 1216

OFF ON ON OFF OFF 20 1280

OFF ON OFF ON ON 21 1344

OFF ON OFF ON OFF 22 1408

OFF ON OFF OFF ON 23 1472

OFF ON OFF OFF OFF 24 1536

OFF OFF ON ON ON 25 1600

OFF OFF ON ON OFF 26 1664

OFF OFF ON OFF ON 27 1728

OFF OFF ON OFF OFF 28 1792

OFF OFF OFF ON ON 29 1856

OFF OFF OFF ON OFF 30 1920

OFF OFF OFF OFF ON 31 1984

OFF OFF OFF OFF OFF 32 2048 - Unframed

(Default)

Note-3.1: The Gateway 2M/2W when set for an N value of 32, operates in Unframed

2Mbps mode

Note-3.2: In E1-V.35 application, the data rate selected for E1 central modem are

downloaded to the V.35 remote modem automatically.


Table 3.10.5B – Data Rate Selection (for V.35 modem only)

SW2-1 SW1-8 SW1-7 SW1-6 SW1-5 SW1-4 n Data Rate Kbps

ON ON ON ON ON ON 1 64

ON ON ON ON ON OFF 2 128

ON ON ON ON OFF ON 3 192

ON ON ON ON OFF OFF 4 256

ON ON ON OFF ON ON 5 320

ON ON ON OFF ON OFF 6 384

ON ON ON OFF OFF ON 7 448

ON ON ON OFF OFF OFF 8 512

ON ON OFF ON ON ON 9 576

ON ON OFF ON ON OFF 10 640

ON ON OFF ON OFF ON 11 704

ON ON OFF ON OFF OFF 12 768

ON ON OFF OFF ON ON 13 832

ON ON OFF OFF ON OFF 14 896

ON ON OFF OFF OFF ON 15 960

ON ON OFF OFF OFF OFF 16 1024

ON OFF ON ON ON ON 17 1088

ON OFF ON ON ON OFF 18 1152

ON OFF ON ON OFF ON 19 1216

ON OFF ON ON OFF OFF 20 1280

ON OFF ON OFF ON ON 21 1344

ON OFF ON OFF ON OFF 22 1408

ON OFF ON OFF OFF ON 23 1472

ON OFF ON OFF OFF OFF 24 1536

ON OFF OFF ON ON ON 25 1600

ON OFF OFF ON ON OFF 26 1664

ON OFF OFF ON OFF ON 27 1728

ON OFF OFF ON OFF OFF 28 1792

ON OFF OFF OFF ON ON 29 1856

ON OFF OFF OFF ON OFF 30 1920

ON OFF OFF OFF OFF ON 31 1984

ON OFF OFF OFF OFF OFF 32 2048 (Default)

OFF ON ON ON ON ON 33 2112

OFF ON ON ON ON OFF 34 2176

OFF ON ON ON OFF ON 35 2240

OFF ON ON ON OFF OFF 36 2304


Table 3.10.6 – Starting Time Slot Selection (Gateway 2M/2W G.703 only)

SW2-5 SW2-4 SW2-3 SW2-2 SW2-1 Starting Time Slot

ON ON ON ON ON 1

ON ON ON ON OFF 2

ON ON ON OFF ON 3

ON ON ON OFF OFF 4

ON ON OFF ON ON 5

ON ON OFF ON OFF 6

ON ON OFF OFF ON 7

ON ON OFF OFF OFF 8

ON OFF ON ON ON 9

ON OFF ON ON OFF 10

ON OFF ON OFF ON 11

ON OFF ON OFF OFF 12

ON OFF OFF ON ON 13

ON OFF OFF ON OFF 14

ON OFF OFF OFF ON 15

ON OFF OFF OFF OFF 16

OFF ON ON ON ON 17

OFF ON ON ON OFF 18

OFF ON ON OFF ON 19

OFF ON ON OFF OFF 20

OFF ON OFF ON ON 21

OFF ON OFF ON OFF 22

OFF ON OFF OFF ON 23

OFF ON OFF OFF OFF 24

OFF OFF ON ON ON 25

OFF OFF ON ON OFF 26

OFF OFF ON OFF ON 27

OFF OFF ON OFF OFF 28

OFF OFF OFF ON ON 29

OFF OFF OFF ON OFF 30

OFF OFF OFF OFF ON 31

OFF OFF OFF OFF OFF 0- Unframed (Default)

Note-3.3: Starting Time Slot is applicable only if the N value selected is not 32.

Note-3.4: In Framed mode the sum of the set value for N and Starting Time Slot

should be less than or equal to 32. In PCM 30 mode, Starting Time Slot

value can not be selected as 16.


Note-3.5: If the above conditions are not met, the 4 Red LEDs will blink continuously

on Power On.

Table 3.10.7 – Transmit & Receive Clock Polarity for DTE (Gateway 2M/2W V.35 only)

SW2-4 Receive Clock Polarity for DTE

OFF Normal (Default)

ON Inverted

SW2-5 Transmit Clock Polarity for DTE

OFF Normal (Default)

ON Inverted

Table 3.10.8 – Clock Modes

SW2-7 SW2-8 Clock Modes

ON OFF Bi-directional External

ON ON Uni-directional External

OFF ON Uni-directional Internal

Table 3.10.9 – Short/Long Haul Operation (Gateway 2M/2W G.703 only)

SW2-6 Short Haul / Long Haul Operation

OFF Short Haul Operation

ON Long Haul Operation

Switch On the Power Switch after the above connections are made and the

configuration is complete, which completes the system installation.


3.11 Clock modes and Applications

The Gateway 2M/2W supports different clock mode as listed in Table 3.10.8. User can

configure the modem according to user’s application and requirement. In below section,

the supported clock modes are listed with the type of application. Recommended

Clock Modes are shaded in Gray.

Table 3.11.1 - Clock Modes for E1 (G.703) – E1 Applications

E1 (G.703) – Central E1 (G.703) – Remote

S.No Mode Source Mode Source

1.1 Bi-Directional External (G.703) Bi-Directional External

1.2 Uni-Directional External (G.703) Uni-Directional Internal (DSL)

1.3 Uni-Directional Internal (Osc) Uni-Directional Internal (DSL)

Table 3.11.2 - Clock Modes for E1 (G.703) – V.35 Applications

E1 ( G.703 ) – Central V.35-Remote


2.1 Uni-Directional External (G.703)

2.2 Bi-Directional External (G.703)

2.3 Uni-Directional Internal (Osc)

Uni-Directional Internal (DSL)

Table 3.11.3 - Clock Modes for V.35 – V.35 Applications

V.35-Central V.35-Remote


3.1 Uni-Directional Internal (Osc)

3.2 Uni-Directional External (DTE) Uni-Directional Internal (DSL)


3.11.1 Transmit and Receive Clock details in different Clock Modes

• Bi-Directional External: In this mode, transmit clock is recovered from

E1/G.703 and receive clock is recovered from DSL line.

• Uni-Directional External: In this mode, transmit and received clocks are

recovered from G.703/DTE.

• Uni-Directional Internal: In this mode, transmit and receive clocks are

generated by the modem.


3.12 LED Indicators

Figure 3.12 - Gateway 2M/2W Front Panel

The following LEDs are provided on the front panel along with functional description of each LED:

PWR ON : Indicates that the modem is reset

OFF : Indicates that the modem is not reset

DIG ON : Indicates that DTE is connected. (DTR is ON in V.35 or G.703

signal in PCM)

OFF : Indicates that DTE is not connected

TD ON : Indicates that steady Space (0’s) is being transmitted

OFF : Indicates that steady Mark (1’s) is being transmitted

Blink : Indicates that data is transmitted

RD ON : Indicates that steady Space (0’s) is being received

OFF : Indicates that steady Mark (1’s) is being received

Blink : Indicates that data is received

SYN ON : Indicates that channel framer is synchronized and frame aligned

with remote modem channel

OFF : Indicates channel framer is not synchronized with remote modem

channel

Slow blink : Indicates that channel continuity detected from remote modem

channel

Rapid blink : Indicates that channel continuity and sync signal detected from

remote modem channel


M/S ON : Modem is configured as Master (DSL-C Central)

OFF : Modem is configured as Slave (DSL-R Remote)

Blink : Indicates that the NMR (Noise Margin of the Receiver) is less than

5dB

AIS ON : Indicates that all 1’s are being received on the G.703 interface in

Unframed mode

Or : Remote Alarm Indication in Framed mode

Blink : Indicates loss of framed in Framed mode

OFF : Indicates normal data is received on the G.703 interface

TST ON : Loopback test (LL, DL or RL) is initiated locally

Blink : RL initiated remotely

OFF : No Loopback is initiated

TP ON : Transmission of selected Test Pattern is initiated from the modem

OFF : Transmission of selected Test Pattern is not initiated from the

modem

Hib ON : Indicates CRC error received on DSL line in normal mode

Or : Indicates received signal sequence has errors in TP mode

OFF : Indicates no error in normal or TP mode


Chapter 4 – Maintenance & Troubleshooting

4.1 How to measure the Quality of Copper Cable

The Gateway 2M/2W measures the quality of copper cable and displays the same on

PC through the MMS port. User will need a PC with RS-232 console port, a

communication software utility, such as hyper terminal and a MMS cable to connect to

the MMS port of the modem with the console port of the PC. The MMS cable details are

given in the Appendix-F and the cable is not supplied with the modem.

4.1.1 Console Port Setup

Connect the RS-232 console port of a PC with the MMS port of the modem. To Start

the Hyper-terminal, follow the steps below.

1. Start "Hyper-terminal" program:

Click on the Start button >> Programs >> Accessories >> Hyper Terminal

Group >> Double Click “Hypertrm.exe” >> Enter Connection Name >>

Select Icon >> Click OK

2. Select a COM port to communicate with the Gateway 2M/2W:

Choose direct to COM1 or COM2 and click on OK

3. Set Port Properties:

Bit per second : 115200

Data bits : 8

Stop bits : 1

Parity bits : None

Flow Control : None


4.1.2 Monitor through Console Port

After connecting Gateway 2M/2W to the console port of the PC, turn it ON. User will

see the current configuration of the modem. After successful connection of the Gateway

2M/2W with the remote modem, indicated by the SYN LED, user will see the ATT

(Attenuation) and NMR (Noise Margin of the Receiver) values in dB on PC. The ATT is

the Attenuation of the copper cable and the NMR is the maximum tolerable increase in

external noise power that still allows for BER of less than 1x10-7. The maximum ATT

and NMR for the below listed Distance/Loop Resistance between Central and Remote

modems should not exceed the approximate value specified in the table below for

stable connectivity.

Table 4.1.1 – Distance/Loop Resistance vs approximate ATT & NMR

ATT NMR Sr. No. Data Rate Distance

Loop

Resistance Remote Central Remote Central

1 2048 Kbps 6 Km 1040 Ohms 34.5 32.5 6.0 7.5

2 1024 Kbps 7.2 Km 1240 Ohms 36.5 34.5 4.0 5.5

3 512 Kbps 8.5 Km 1470 Ohms 37.5 35.5 3.5 4.5

4 192 Kbps 10.2 Km 1760 Ohms 38.5 36.5 3.0 3.5

For example, for the Distance of 6 Km and Loop Resistance of 1032 Ohms, at the Data

Rate of 2048Kbps, the ATT value should not be more than 34.5 dB in Remote and 32.5

dB in Central. The NMR value should be better or equal to +6.0 dB in Remote and 7.5

dB in Central for the best line conditions. In this case, for the BER of less than 1x10-7,

the maximum tolerable increase in external noise power is 6dB in Remote and 7.5 in

Central.

Note-4.1.: The low NMR is also indicated by the M/S LED on the front panel of the

modem. If the NMR is less than 5dB the M/S LED will blink and if the NMR

is more than the 5dB this LED will be ON/OFF depending on Master/Slave

mode selection.


4.2 Diagnostic Tests

The Gateway 2M/2W modems are equipped with the following diagnostic tests

capability:

• Local loopback test

• Digital loopback test

• Remote loopback test

• Bit error rate test

4.2.1 Local Loopback Test

This test is used to loopback the data received on the digital interface (V.35 or G.703)

of the Local modem. Once the local loopback test is initiated, an external Bit Error Rate

Tester (BERT) can be used to send a test pattern and check the received (loopback)

data for errors.

Figure 4.2.1 – Local loopback

1. To initiate the Local loopback test, turn ON the power switch of the

modem.

2. Press the LL switch, TST LED indicates that Local loop is initiated.

3. When the test pattern of the BERT is turned ON, it will receive back the

transmitted data, and measure the BER.


4. This test indicates that the Data from the BERT is looped back locally to

the BERT and thus the performance of the Local Modem can be

observed.

If the DTE is connected with the modem, this test checks the satisfactory working of the

Local modem, the DTE and the connection between them as shown in Figure 4.2.1.

4.2.2 Digital Loopback Test

This test is used to loopback the data received by the Local modem on the DSL line

back to the Remote modem. Once the digital loopback test is initiated, a BERT can be

connected to the Remote modem to send a test pattern and check the received

(loopback) data for errors.

Figure 4.2.2 – Digital loopback

1. Make the power connections and the channel (line) connection of the

Local modem and the Remote modem. Ensure both modems are synced

up as indicated by the SYN sync LED.

2. The BERT is to be connected to the Remote modem to perform this test.

3. To initiate the test, press the DL switch once on the front panel. TST LED

will become On.

4. When the test pattern of the BERT is turned On, it will receive back the


If the DTE is connected with the Remote modem, this test checks the satisfactory

working of the Local modem, the Remote modem, DTE connected to the Remote

modem and the connection between them as shown in Figure 4.2.2.


4.2.3 Remote Loopback Test

This test is initiated by the Local modem and is used to loopback the data received by

the Remote modem on the DSL line back to the Local modem. Once the remote

loopback test is initiated, a BERT can be connected to the Local modem to send a test

pattern and check the received (loopback) data for errors. With this test, one can verify

the same things as with digital loopback test. The only difference is that the loop is not

made on the Remote modem, but on the Local modem. This can be necessary when,

for example, the remote modem can not initiate digital loopback.

Figure 4.2.3 – Remote loopback

1. Make the power connections and the channel (line) connection of the

Local modem and the Remote modem. Ensure both modems are synced

up as indicated by the SYN sync LED.

2. The BERT is to be connected to the Local modem to perform this test.

3. To initiate the test, press the RL switch once on the front panel. TST LED

will become On on Local modem and on Remote modem TST LED will

start blinking.

4. When the test pattern of the BERT is turned On, it will receive back the


If the DTE is connected with the Remote modem, this test checks the satisfactory

working of the Local modem, the Remote modem, DTE connected to the Remote

modem and the connection between them as shown in Figure 4.2.3.


4.2.4 Bit Error Rate Test

Whether a test is in progress or not, pressing the TP will cause the modem to ignore

data received on the Digital Interface from the DTE. It will cause the modem to

generate a pseudo-random 511 (2e9) pattern and transmit it on the line. It will

simultaneously check all incoming data for the 511 pattern. If the 511 pattern is

received without errors, the TP LED will stay ON. If the 511 pattern is received with

errors, the HiB LED will blink whenever there are errors. This test can be used in

conjunction with the Digital Loopback, Remote Loopback and Far-end Remote

Loopback tests, particularly when a BERT is not available. This test cannot be used

in conjunction with Local Loopback test.

1. Make the power connections and the DSL Line connections of the Local

modem and the Remote modem. Ensure both modems are synced up as

indicated by the SYN sync LED.

2. Loop the line at the remote side, by pressing the RL switch at the local

side or the DL Switch on the remote side.

3. Press the TP Switch of the local modem, TP LED on the front panel will

be on. The TP LED will blinking, indicating that the Test Pattern is syncing

and will become stable after Test pattern sync. If the received signal has

errors the Hib LED will blink.

Note : The desired test (DL or RL) has to be applied first and then the test

pattern (TP) has to be initiated for accurate results

4. Alternately, press the TP Switch of both the local and remote modems,

and observe the status of HiB LED on both modems.

Note: DL, RL and TP Tests shall be automatically turned Off when the

modem looses its Synchronisation with remote modem.

4.2.5 System Reset

Pressing RST switch will cause the modem to initiate the start up sequence as

explained in the operation procedure. During this time, the data through the modem will

be disrupted until it returns to normal operation.


Table 4.2.1 Trouble Shooting

LED’s Status Description Probable failure

MR OFF Indicates that the Modem power is not present

Check the input power to the modem or the Fuse of the modem

DIG OFF Indicates the loss of DTE Signal

Check the DTE connections for proper TX and RX installation if G.703 modem or DTR signal from DTE if V.35 modem.

TD OFF Indicates the Loss of transmit data

Check the local DTE

RD OFF Indicates the Loss of Receive data

Check the remote DTE

SYN OFF Indicates Channel (Line) continuity not detected with remote modem

Check the cable pair of Channel (Line) between the modems

SYN Blink Indicates Channel (Line) Framer is not synchronized with remote modem

Check the cable pair of Channel (Line) and line condition (attenuation and noise on line) between the modems

AIS ON For Remote Alarm Indication in G.703 framed mode

Check the PCM connectivity from the Exchange.

Hib ON Indicates CRC errors received on DSL

Check for the proper Earthing and then cable pair attenuation and noise.

TP ON or Blink

Test Pattern test is initiated locally

Indicates that the modem is under test


Chapter 5 – Technical Support & Warranty

5.1 Technical Support Sheet

For any problem related to the modem, kindly fill this form completely and send by email to [email protected] OR [email protected]. We shall promptly contact you back on e-mail / phone no. given on this form to provide technical support. Please do not ship physical modem from the site without confirmation from our end. 1. Name of the modem installation site:___________________________ Location: ________________

2. Address of Installation site: ___________________________________________________________

3. Tele No with STD code: _____________________________________________________________

4. Contact Person Details: - Name:_______________________________________________________

(Name of the field engineer at site)

E-mail Id: - ______________________________________ Mobile No.: ____________________

5. Product Description: - Model: ____________________ Sr. No(s).:____________________________

6. Symptoms/Fault reported (No POWER/ No SYNC/ No DATA TRANSFER): -

________________________________________________________________________________

Feedback / Observation:

• Input Power Source (230V AC or 48V DC) : _____________________________________________

• Dip Switch Settings:

In G.703: ______________________________________________________________________

In V.35: _______________________________________________________________________

• LED Indication on the modem/s:_______________________________________________________

(Pl indicate the LEDs which are in ON condition at the time of problem)

• Back to back testing: (Passed/Failed ) __________________________________________________

• Outcome of any other test / swapping with working modems:- _______________________________

• Details of the Router/Mux Connected to the modem _______________________________________

• Any other Additional info _____________________________________________________________

Details of shipping location: (This could be same as installation site or any other place from where the modem will be shipped to our repair centre at Hyderabad at address below) Name of person and contact no.s: ________________________________________________________

Address where it has to be returned back after repair: _________________________________________

____________________________________________________________________________________

(Defective modems to be shipped to Nomus repair Centre at address below)

Address : Customer Support Dept., NOMUS COMM-SYSTEMS 9A, Commercial Complex, Srinagar Colony, Hyderabad – 500 073 Email : [email protected]

Tel : +91-(040) 2374 4334 /1720

Fax : +91-(040) 2374 4335

Mobile : +91-93922 44335, +91-93928 44335


If your modem has to be returned, Nomus Comm-Systems will confirm whether your

modem is still covered by a warranty. If it is not, Nomus will estimate the repair charge.

However, the repair charge might be different, after Nomus Comm-Systems inspects

your modem. If the charge were to be greater than the estimate, or if your modem is

later determined to be out of warranty, Nomus Comm-Systems will contact you for your

approval or instructions. Ship the modem to Nomus Comm-Systems at the above

address, freight pre-paid and with declaration stating "Data Modem for repair only.

No Commercial Value". After repairs are complete, Nomus Comm-Systems will ship

the modem back to you freight prepaid by a cost effective method of Nomus Comm-

System's choosing.

Nomus Comm-Systems designs and manufactures exceptionally high quality products.

Each product is subjected to extensive testing and stringent quality control procedures.

Even though, your modem is covered by a parts and labour limited warranty. Following

is the complete explanation of the warranty.

5.2 Nomus Comm-Systems Limited Warranty

Nomus Comm-Systems warrants to the original customer or purchaser its hardware

products to be free from defects of materials and workmanship for 12 (twelve) months

from the date of installation or 15 (fifteen) months from the date of delivery, which ever

comes earlier. This warranty covers parts and labour. Upon verification of warranty

status, Nomus Comm-Systems will, at its discretion, repair or replace the Nomus

Comm-Systems product. This warranty is valid only where the Nomus Comm-Systems

product is used in the application for which it is intended, and has not been subjected to

unusual physical or electrical stress, and has not been modified or repaired without

prior written approval of Nomus Comm-Systems.

Nomus Comm-Systems' liability under this warranty shall be limited to refund of the

purchase price of its product. In no event shall Nomus Comm-Systems be liable for

costs of procurement of substitute goods by the buyer. In no event shall Nomus Comm-

Systems be liable for any special, consequential, or incidental damages, however

caused, whether for breach of warranty, breach of contract, repudiation of contract,

negligence, or otherwise.


Appendix A – Technical Specification

Line Interface

Line Code TCPAM as per ITU-T G.991.2 (G.SHDSL)

Line Rate (R+8 Kbps) / 3, where R is the Data Rate

Line Type 2-wire or 4-wire Unconditioned Twisted Copper Wire

Connector RJ45

Line Impedance 135 Ohms Balanced

Range KM 6.0 Km @ 2 Mbps, 10 Kms @ 192 Kbps on 24 AWG (0.5 mm) copper wire

Digital Interface G.703 (E1) V.35

Line Code HDB3 as per ITU-T G.703 standard Balanced Line Driver/ Receiver for Switching signals

Compatibility ITU-T G.703, G.704. Framed/Unframed. CCS/CAS Signaling. ISDN Primary Rate

ITU-T V.35, X.21 or RS-530 (Option)

Data Rate 2.048 Mbps nx64 Kbps, n=1 to 36 (2-wire)

Transmit Clock Recovered from G.703 Signal, Internal External, Internal, Recovered from Line

Connector RJ45 Balanced or 2 nos BNC Unbalance 34 Pin Female standard connector or 25 Pin Female D-type connector

Line Impedance 120 Ω Balanced or 75 Ω Unbalanced

MMS Interface RJ45 Jack for connection to a PC for monitoring & diagnostics

Diagnostics

Local Loopback Data received on the Digital (V.35/G.703) Interface is looped back on Transmit Data

Digital Loopback Data received on the Line is looped back on the line to the Remote modem

Remote Digital Loopback Remote modem is requested to loopback Receive Data to Transmit Data before the Digital (V.35/G.703) Interface

BERT- Bit Error Rate Test In built test pattern ( 511 ) generation and detection

Indicators MR, DIG, TD, RD, SYN, M/S, TST, TP, AIS, HiB

Power V.35 : 230VAC +/-10%, 0.1A Earthed Power G.703 : 230VAC +/-10%, 0.1A and 48VDC +/- 10%, 0.3A Earthed Dual Power

Mechanical 210mm (D) x 170mm (W) x 45mm (H) Metal Casing, 1.2 Kg Weight

Operating Conditions 0o

C to 50o

C; 90% Humidity

TEC Approval No TEC/WR/I/DCA-18/04/184

Ordering Information Gateway 2M/2w (2-wire), Gateway 2M/4w (4-wire); Use LX suffice for LCD option


Appendix B – V.35 Interface

Pin Number Pin Name Input/Output

A Frame Ground N/A

B Signal Ground N/A

C Request To Send CTS Input

D Clear To Send CTS Output

E Data Set Ready DSR Output

F Carrier Detect DCD Output

H Data Terminal Ready DTR Input

P Transmit Data A Input

S Transmit Data B Input

R Receive Data A Output

T Receive Data B Output

Y Transmit Signal Timing A Output

AA Transmit Signal Timing B Output

V Receive Signal Timing A Output

X Receive Signal Timing B Output

U Terminal Timing A Input

W Terminal Timing B Input

L Local Loopback Input

N Remote Loopback Input

NN Test Mode Output


Appendix C – RS-530 Interface

Pin Number Pin Name Input/Output

1 Shield N/A

7 Signal Ground N/A

2,14 Transmit Data A,B Input

3,16 Receive Data A,B Output

4,19 Request To Send A,B Input

5,13 Clear To Send A,B Output

6,22 Data Set Ready A,B Output

20,23 Data Terminal Ready A,B Input

8,10 Carrier Detect A,B Output

24,11 External Clock A,B Input

15,12 Transmit Clock A,B Output

17,9 Receive Clock A,B Output

18 Local Loop Input

21 Remote Loop Input

25 Test Mode Output


Appendix D – G.703 Interface

RJ45 Pin Number Pin Name Wire Color

1 TX1 Orange

2 TX2 Orange white

4 RX1 Green

5 RX2 Green White

G.703

TX

RX

2M G.703/E1 interface

from PCM/DTE

2M G.703/E1 interface

to modem

REDGREEN

YELLOW BLACK

RJ45 Pin details


Appendix E – Line Interface

RJ45 Pin Number Pin Name Wire Color

1 Limb 1 Orange

2 Limb 2 Orange white

DSL

LINE

CH1

CH2

From Remote modem

DSL LINE

To Local modem

DSL LINE

REDGREEN

BLACKYELLOW

RJ45 Pin details


Appendix F – MMS Cable Details

9 Pin D Female Connector Pin Number

Pin Name RJ45 Pin Number

3 TX 3

5 Ground 4

2 RX 6

RJ45 Pin details


TEC Approval Certificate

gateway 2m 2w v5

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