8/3/2019 g703fe1 Quick Start Guide

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This document subject to change without notice. CTC Union accepts no responsibility for errors or mistakes in thisdocument. Unauthorized modification of equipment may result in warrantee becoming void even during the

warrantee period. Please contact your distributor for the latest support for your equipment.

Quick Start and Application NotesModel: G703E1/FE1/FE1A

This model is a single port E1 access unit. The E1 port has either unbalanced BNC or balanced RJ-45.

Only one may be used at a time. The impedance setting is done by DIP switch. Set 75 Ohm for BNC or

120 Ohm for RJ-45.

Because this unit has been in production for a very long time, it is very stable. Most inquiries for support

revolve around mis-understanding of terminology leading to mis-configuration of the DIP switches.

Please follow the check points below when troubleshooting the use of this unit.

E11. PHYSICAL: E1 RJ-45 now uses a USOC standard pin assignment. However, the G703FE1 was

developed long before this standard. Take extra care and note TTip/TRing are pins 3/6 while RTip/RRing

are 4/5. Set SW1-1~5 all OFF for balanced 120 Ohm or all ON for unbalanced 75 Ohm operation.

2. CLOCK: E1 operation requires a single clock source. In a point to point application, one unit must be

a clock source while the other is a clock receiver. To accomplish this, set one unit to Int.Osc. DS6-1~2ON-ON, while the other unit is set to recovery DSW6-1~2 ON-OFF. In an E1 network setting, the clock

will always come from the received E1 signal and will be the source for the transmitted E1. Recovery

setting is correct for all E1 network applications.

3. FRAMING: In order for E1 devices to properly synchronize and communicate, they must have the

same type of framing and line code. Line code is easy as in almost all cases it will be HDB3. The

G703FE1/FE1A only supports HDB3 coding. The G703E1-U has selectable coding between HDB3 or

AMI. Framing may be set as unframed, DIPSW2-1 OFF, or fractional E1, DIPSW2-1 ON. Additionally,

in fractional mode you must set the framing type (PCM30 or PCM31) with DIPSW6-6 (ON for PCM31)

and also whether CRC4 is used or not (DSW6-5 ON=enabled)

4. TIMESLOTS: The last E1 parameter that needs configuring is the timeslot assignment. The G703FE1

pack series supports random timeslot assignment. DIPSW2 thru DIPSW5 control the individual timeslot

enable or disable. If unframed mode is chosen, these assignment switches will be ignored.

If all of the above steps have been confirmed and connections are proper, there should be no 'Alarm' LED

lit with the units powered on.

DATAPORT1. The data port on the G703 pack series is RS-530 standard with adapter cables that provide connection

to V.35, X.21, and RS-449 equipment. The G703 pack supports both DCE and DTE modes by DIP switchsetting. This makes it convenient when connecting to other equipment using our standard cable without

doing any crossover. Just be sure to check the type of connecting equipment. For example, when

connecting to a router, that device is usually DTE. Therefore, set the G703FE1 as DCE and connect

directly. If connecting to another modem or multiplexer, these devices usually have DCE interfaces.

Therefore, in this case, change the data port type to DTE on the G703FE1. The timing will probably also

need to be set to receive clock from the data port, since DCE devices supply clock.