Black Box MTU200-N64M User manual

Standalone G-Converter
G.703/G.704 to Nx64 X.21/V.35 Converter
TECHNICAL:
SALES:
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ADDRESS:
WEB:
[phone]
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464 Basingstoke Road, Reading, Berkshire RG2 0QN
www.blackbox.co.uk
Standalone G-Converter:
MTU200-N64M
9th June 2000
Rev 1.0

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Standalone G-Converter
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Standalone G-Converter
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Standalone G-Converter
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Standalone G-Converter
G.703/G.704 to Nx64 X.21/V.35 Converter
User Manual
WARNING - BEFORE INSTALLATION, PLEASE REFER
TO SAFETY INSTRUCTIONS IN APPENDIX A, AND
EMC INSTRUCTIONS IN APPENDIX C
Certified Compliant in the EC, when fitted in accordance with the installation instructions,
against the following directives/standards:
Low Voltage Directive (73/23/EEC and amendment 93/68/EEC)
EN60950 : 1992 (Safety)
Electromagnetic Compatibility directive (89/336/EEC and subsequent
amendments to date):
EN55022 : 1994 (Emissions)
EN50082-1 : 1992 (Immunity)
Telecommunications Terminal Equipment directive (91/263/EEC and
amendment 93/68/EEC) where indicated in approvals requirements section.

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Standalone G-Converter
TECHNICAL: 0118 931 2233
Contents
Introduction..............................................................................................................................................7
Local Control...............................................................................................................................7
Remote Control...........................................................................................................................7
Operating Modes.....................................................................................................................................8
Operating Mode 1.......................................................................................................................8
Operating Mode 2.......................................................................................................................8
Operating Mode 3.......................................................................................................................9
Operating Mode 4.......................................................................................................................9
G.703 Interface Presentation.................................................................................................................10
75 ohm operation......................................................................................................................10
120 ohm operation....................................................................................................................10
Selection and Configuration Of DCE Interface.......................................................................................11
X.21/V.11 Interface...................................................................................................................11
Control Of “I” Lead.......................................................................................................11
V.35 Interface............................................................................................................................11
Configuration Of V.35 Control Flags............................................................................12
Remote Loopback Function...................................................................................................................13
External Clock........................................................................................................................................14
External Clock without Autobauding.........................................................................................14
External Clock with Autobauding..............................................................................................14
Configuration..........................................................................................................................................15
DIL switch settings....................................................................................................................16
Default Unit Set-Up...................................................................................................................17
Front panelLED indicators........................................................................................................18
Diagnostics............................................................................................................................................19
Front Panel LEDs......................................................................................................................19
Seven Segment Display............................................................................................................19
Loopbacks................................................................................................................................19
Installation..............................................................................................................................................21
Supply Voltage and Connection................................................................................................21
Environmental Considerations..................................................................................................21
Mechanical Construction...........................................................................................................21
Back-To-Back Demonstration Connection.............................................................................................22
75 ohms BNC toPD7024 interfaces.........................................................................................22
120 ohms RJ45 twisted pair to CTR 12 interfaces....................................................................22
Appendix A - Warnings..........................................................................................................................23

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Standalone G-Converter
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Appendix –B Approval Requirements....................................................................................................26
G.703/G.704.............................................................................................................................26
Appendix C – EMC Requirements.........................................................................................................27
Limitation of Emissions:............................................................................................................27
'D-Type' Connections...................................................................................................27
Appendix D -Location Of Switches and Links........................................................................................28
Appendix E - G.703 Interface Pin Outs..................................................................................................29
Appendix F - RJ45 E1 Crossover Cable................................................................................................30
Appendix G- X.21/V.11 DCE Pinout.......................................................................................................31
Appendix H – V.35 DCE Pinout.............................................................................................................32
Appendix I –V.35Stub Cable................................................................................................................33

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Standalone G-Converter
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Introduction
This manual provides information covering installation and set-up procedures of the
converter.
A full set of cable pin-outs and a PCB layout (showing the location of switches and link
settings) are included in the appendices.
The G-Converter is an interface adapter that will convert between a G.703/G.704 link and an
X.21/V.11 or V.35 interface. The intended use of this unit is to terminate a G.703/704 link;
DCE rates between zero and 2048kbps in 64k steps. Selection of these DCE rates is
conveyed across the G.703/G.704 link from the central site management unit by a proprietary
in-band signalling scheme.
An external clock input is provided on the DCE port to enable the G-Converter to be clocked
from the connected DTE.
Configuration of the G-Converter is achieved in two simple stages involving internal and
external switches, and selection of internal links.
Local Control
When the converter is configured as Local (Internal switch: SW4, 1 = off) the DCE rates are
selected by using the two rotary switches, identified as XIO and X1, located on the front of
the unit. As each switch is rotated, using a screwdriver, the relative position sets the number
“N” which is displayed on the seven-segment LED display. X10 selects tens, X1 selects
units, permitting selection of N =0 to a maximum of 32. When local mode is selected the
decimal point of the right hand digit of the seven-segment display is illuminated.
DCE rate allocation is N x 64kbps, so an indication of N = 23 signifies a DCE rate of
1472kbps. The information that N = 23 is encoded and transmitted across the link in time
slot 31.
Remote Control
When the converter is configured as Remote, (Internal switch SW4, 1 = on) the DCE rate is
controlled by the control information being received in time slot 31. Configuration of the
DCE speed on this remote unit is controlled by the ‘Local’ unit since the front panel switches
will be deactivated.

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Standalone G-Converter
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Operating Modes
The equipment has four operating modes: Refer to the Switch and link location diagram in
Appendix D -Location Of Switches and Links.
Operating Mode 1
G.703 Transparent interface converter, data rate fixed at 2048kbps,
Remove the cover of the unit, locate Internal Switch 4 and set as follows:
SW4,1 SW4,2 SW4,3 SW4,4 SW4,5 SW4,6 SW4,7 SW4,8
NR NR NR NR NR OFF OFF OFF
N.B. NR = Not Relevant.
The external Loop switch (front panel) should be set as Normal.
In this mode the data is routed directly from the G.703 interface to the X.21/V.11 interface.
The rotary switch settings are ignored and time slot 31 is not monitored. In transparent mode
the G-Converter may be connected to other suppliers G.703 to X.21/V.11 converters.
Operating Mode 2
G.703 Interface, data rate configurable between Zero and 2048kbps.
Remove the cover of the unit, locate Internal Switch 4 and set as follows:
SW4,1 SW4,2 SW4,3 SW4,4 SW4,5 SW4,6 SW4,7 SW4,8
✷
✷✷
✷OFF OFF NR NR ON OFF OFF
N.B. NR = Not Relevant.
✷
✷✷
✷When converters are to be set up as a pair, one unit MUST be configured as a Local unit
(SW4, 1 = Off) and the other a Remote unit (SW4, 1=On)
The external Loop switch (front panel) should be set as Normal.
In this mode DCE data rates may be selected between 0bps and 2048kbps in 64kbps steps. A
proprietary framing scheme is used to control the value of N.
It is recommended this mode is used only if data rates up to 2048kbps are required as a fault
condition on the G.703 link could force the DCE clock to operate at 2048kbps. If the user
equipment is only capable of running at say 256kbps then this may cause problems.

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Standalone G-Converter
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Operating Mode 3
G.703 Interface, data rate configurable between 0bps and 1984kbps
Remove the cover of the unit, locate Internal Switch 4 and set as follows:
SW4,1 SW4,2 SW4,3 SW4,4 SW4,5 SW4,6 SW4,7 SW4,8
✷
✷✷
✷OFF ON NR NR ON OFF OFF
N.B. NR = Not Relevant.
✷
✷✷
✷When converters are to be set up as a pair, one unit MUST be configured as a Local unit
(SW4, 1 = Off) and the other a Remote unit (SW4, 1=On)
The external Loop switch (front panel) should be set as Normal.
In this mode, data rates may be selected between 0bps and 1984kbps in 64kbps steps. A
proprietary framing scheme is used to control the value of N.
Use this mode if you are sure you will not want to use N = 32 (i.e. 2048kbps).
When operating in this mode, a fault condition on the G.703 link will force the DCE clock to
operate at 0kbps and display “Er” on the display.
Operating Mode 4
G.704 Interface, data rate configurable between 0bps and 1984kbps
Remove the cover of the unit, locate Internal Switch 4 and set as follows:
SW4,1 SW4,2 SW4,3 SW4,4 SW4,5 SW4,6 SW4,7 SW4,8
✷
✷✷
✷ON NR NR NR ON OFF OFF
N.B. NR = Not Relevant.
✷
✷✷
✷When converters are to be set up as a pair, one unit MUST be configured as a Local unit
(SW4, 1 = Off) and the other a Remote unit (SW4, 1=On)
The external Loop switch (front panel) should be set as Normal.
In this mode, all speeds are possible between 0bps and 1984kbps in 64kbps steps. A
proprietary framing scheme is used to control the value of N.
Operating Mode 4 would be used if you were connected to a G.704 network. In this mode, a
fault condition on the G.704 link could force the DCE clock to operate at 0kbps and flash
“Er” on the display.

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Standalone G-Converter
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G.703 Interface Presentation
The converter may be configured to operate on either a 120 ohm balanced circuit impedance,
presented on an RJ45 connector or with a 75 ohm unbalanced impedance, presented on two
BNC connectors.
Selection of the interface is made by link settings – refer to Appendix D -Location Of
Switches and Links for the location diagram and use in conjunction with the tables below.
75 ohm operation
LINK
NUMBER FUNCTION SETTING
LK1 Connects BNC TX Fitted (ensure shorted pins run
front to back of unit)
LK5 Connects BNC RX Fitted (ensure shorted pins run
front to back of unit)
LK3 Determines TX transformer
ratio Positions 2 and 1
LK4 Determines RX transformer
ratio Positions 2 and 1
LK6 AC couples screen of RX
BNC to gnd Position 2 and 3 for coupling * Position 1 and 2 for no coupling*
LK2 AC couples screen of TX
BNC to gnd Position 2 and 3 for coupling* Position 1 and 2 for no coupling*
Notes:
*This setting is application dependent. Only one end of each link should be grounded to
prevent ground loops, therefore the position of these links needs to made in conjunction with
the installation grounding scheme.
120 ohm operation
LINK
NUMBER FUNCTION LINK SETTING
LK1 Connects BNC TX Remove
LK5 Connects BNC RX Remove
LK3 Determines TX transformer
ratio Positions 2 and 3
LK4 Determines RX transformer
ratio Positions 2 and 3
LK6 AC couples screen of RX
BNC to gnd Position 1 and 2 for no coupling
LK2 AC couples screen of TX
BNC to gnd Position 1 and 2 for no coupling

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Selection and Configuration Of DCE Interface
The DCE port of the G-Converter can be presented as either X.21/V.11 or V.35 Choice of
interface is made by link setting. The X.21/V.11 interface is presented on a 15-way D type
connector in accordance with ISO 4903. The V.35 interface is also presented on the same 15
way D-type connector. A converter cable is optionally available.
X.21/V.11 Interface
Selection of the interface is made by link settings – refer to Appendix D -Location Of
Switches and Links for the location diagram. To select the X.21/V.11 interface Link 9
jumper must be in the X.21 position. The connector pin out for the X.21 interface is given in
Appendix G
Control Of “I” Lead
When the X.21/V.11 interface is selected, the “I” lead function can be controlled. The “I”
lead status is synthesised by the converter since no information about the “I” lead status is
passed across the link. Status of the “I” lead is fixed. Four choices are available to the user.
Selection is made via switch settings. Refer to the location diagram in Appendix D -
Location Of Switches and Links
SW4, 4 SW4, 5 FUNCTION OF I LEAD
OFF OFF I follows C lead
OFF ON I = active
ON OFF I = inactive
ON ON I follows carrier
V.35 Interface
Selection of the interface is made by link settings – refer to Appendix D -Location Of
Switches and Links for the location diagram. To select the V.35 interface link 9 must be in
the V.35 position. The V.35 interface is presented on the 15 way D-type connector. Two
“control flags” are available as outputs and one “control flag” is available as an input. The
V.35 specification calls for the following Control signals;
V.35 CONTROL FLAG SIGNALS
Name Description Type at Connector Signal number
RTS Request To Send Input 105
CTS Clear To Send Output 106
DSR Data Set Ready Output 107
DCD Data Carrier Detect Output 109

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Standalone G-Converter
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The G-Converters support one input flag and two output flags. It is up to the user which of
the signals is to be implemented. RTS would normally be the definition for Flag 1 I/P
(although is does not have to be) as this is the only I/P called up by the V.35 spec.
The two output flags, Flag 2 O/P and Flag 3 O/P can be assigned to either CTS, DSR or
DCD, the choice is at the discretion of the user.
The connector pin out for the V.35 interface is given in Appendix H and a suggested stub
cable converter to 34 pin MRAC is given in Appendix I – V.35 Stub Cable.
Configuration Of V.35 Control Flags
When the V.35 interface is selected the FLAG 1 O/P and FLAG 2 O/P can be individually
controlled. Four choices are available to the user.
Selection is made via switch settings. Refer to the location diagram in Appendix D -
Location Of Switches and Links.
SW4, 4 SW4, 5 FUNCTION OF O/P
FLAG 1
OFF OFF FLAG 1 O/P follows
FLAG 3 I/P
OFF ON FLAG 1 O/P = active
ON OFF FLAG 1 O/P = inactive
ON ON FLAG 1 O/P follows
carrier
SW5, 2 SW5, 3 FUNCTION OF FLAG 2
O/P
OFF OFF FLAG 2 O/P follows
FLAG 3 I/P
OFF ON FLAG 2 O/P = active
ON OFF FLAG 2 O/P = inactive
ON ON FLAG 2 O/P follows
carrier

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Standalone G-Converter
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Remote Loopback Function
If the stand-alone G-Converter has SW5, 1 to off, the Manager card located in the card cage
may select a remote loopback. Once this state has been entered, it will remain in loopback
for approximately 3 minutes. Whilst in loop back, the LED display will flash “rL”, the data
and clock being outputted through the DCE port will be suppressed and the data arriving at
the X.21/V.35 drivers/receivers will be looped back to the central site.

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Standalone G-Converter
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External Clock
The G-Converters have the ability to use as its clock source a clock supplied from the
connected DTE. An external clock is supplied externally to the converter via the EXT clock
pins, of the 15 way D type connector (pins 7 and 14). Whenever an external clock is used,
the rightmost decimal point of the seven-segment display is illuminated.
The two external clock modes are :-
External Clock without Autobauding
This mode is selected by switching SW4,7 to On and SW5,4 to OFF. In this mode the
external clock being supplied must be 2048Kbps +/- 50 ppm and the jitter content compliant
with the requirements of TBR12 and PD 7024. The function of the G-Converter in this mode
is identical to operation with recovered clock (normal operation) with the exception that the
clock source is from the external clock and not the G.703/4 link.
In this mode, if the received clock Frequency is grossly Out of spec (or absent) then the
letters “Fo” will be alternately flashed with the N value on the LED display. At all times the
assumption is made that the clock being supplied to the G-Converter from the G.703/4
network is as per TBR12/PD7024 requirement.
When this mode is selected and operating correctly, the display should be steady with the
rightmost decimal point flashing.
External Clock with Autobauding
This mode is selected by switching SW4,7 to On and SW5,4 to ON. In this mode the
external clock, being supplied must be Nx 64Kbps +/- 50 ppm and the jitter content
compliant with the requirements of TBR12 and PD 7024. The function of the G-Converter in
this mode will measure the external clock and set the operation of the G-Converter to this
speed. In this mode, the unit will become a Local.
In this mode, if the received clock Frequency is grossly Out of spec (or absent) then the
letters “Fo” will be alternately flashed with the N value on the LED display. The N value will
still be derived from the external clock and the data will be clocked out of the DCE with this
clock, however the G.703/4 link will be clocked from the G.703/4 recovered 2048Kbps
clock. At all times the assumption is made that the clock being supplied to the G-Converter
from the G.703/4 network is as per TBR12/PD7024 requirement.
When this mode is selected and operating correctly, the display should be steady (indicating
the external clock speed) with the rightmost decimal point flashing.

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Standalone G-Converter
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Configuration
Configuration of the G-Converters is achieved in two simple stages involving internal and
external switches, and setting of some internal links. Refer to Appendix D -Location Of
Switches and Links for details of Internal Switch and link locations.
Selection of internal links permit the converters to operate either as a Local or Remote unit.
Rotation of the two external switches release bandwidth in Nx64k allocations. An LED
display will confirm the link rate selected.
Notes:
1Front panel switches are disabled when Remote is selected on a unit.

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DIL switch settings
The mode of operation is set up using the DIL switches SW4 and SW5.
SW POSITION FUNCTION SETTING
SW4, 1 Selects either remote
operation or local operation Off = local On = remote
SW4, 2 Selects interface type Off = G.703
On = G.704
SW4, 3 Allows unframed operation On = unframed operation not permitted
Off = unframed operation permitted1
SW4, 4
SW4, 5 Sets up operation of X.
When X.21/V.11 interface
set.
X= I lead
Y= C lead.
When V.35 interface set
X= FLAG 1 O/P,
Y= FLAG 3 I/P
SW4, 4 = off, SW4, 5 = off,
Xfollows Y
SW4, 4 = on, SW4, 5 = on,
Xfollows Carrier
SW4, 4 = off, SW4, 5 = on,
X= active
SW4, 4 = on, SW4, 5 = off,
X= inactive
SW4, 6 Sets G-Converter to
permanent
Transparent mode 2048kbps
Off = permanent straight through2
On = framed/unframed
SW4, 7 Sets G.70x TX off if no
G.703 RX detected Off=G.703 TX enabled always. On = G.703 TX disabled in the event of
G.703 RX not being present4
SW4, 8 Use External Clock3On = Use external clock. Off = do not
use external clock.
SW5,1 Enables Remote Loopback
function Off = Remote loop back enabled. On = Remote loop back disabled
SW5, 2
SW5, 3 Sets up operation of FLAG 2 O/P “X“ when set for V.35
interface
SW5, 2 = off, SW5, 3 = off,
Xfollows Flag3 I/P
SW5, 2 = on, SW5, 3 = on,
Xfollows Carrier
SW5, 2 = off, SW5, 3 = on,
X= active
SW5, 2 = on, SW5, 3 = off
X= inactive
SW5,4 Sets Autobauding on or off Off = Autobauding not selected
On = Autobauding selected
N.B for Autobauding SW4,8 must be
set to on
Factory default switch settings – 75 Ohm

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Standalone G-Converter
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Notes:
1 Only allow unframed operation if a DCE speed of 2048Kbps will not “harm” the DTE.
2 Use this mode if no in-band management is required and the link is required to run a
permanent 2048Kbps. Also, use this mode if interfacing to another manufacturers
G.703/X.21 interface converter.
3When an external clock is used it must be 2048Kbps +/- 50ppm as per TBR12/PD7024 for
non Autobauding operation or Nx64Kbps +/- 50ppm for auto baud operation.
4 Use this option if it is required to suppress TX data in the event of loss of RX data from the
G.70x link.
Default Unit Set-Up
When delivered, the G-Converter is set to operate as follows:
Interface selected : X.21 (LK9 to X.21 position)
Local/Remote : Local (SW4, 1 = off)
G.703/G.704 Interface : G.703 (SW4, 2 = off)
Allow Unframed : Yes (SW4, 3 = on)
I Lead Control : Follow Carrier (SW4,4=SW4,5 = on)
Permanent Straight Through : Not selected (SW4, 6 = on)
G.70x TX : Always enabled (SW4, 7 = off)
External Clock : Not selected (SW4,8 = off)
Remote loopback : Enabled(SW5,1 = off)
Autobauding : Not selected (SW5,4 = off)
Interface Impedance : 75 Ohms (Un-balanced) see table
above in G.703 interface
presentation section.
Front Panel loop switch enabled : Enabled (LK12 position 1 and 2)
Front panel loop switch : Off (centralised)

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Standalone G-Converter
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Front panel LED indicators
The G-Converter has 4 LED indicators: -
LED LABEL CONDITION NOTES
CARRIER ON
OFF
RX Carrier established
No RX Carrier established.
LOOP ON
OFF
Either a Local loop or a remote
loop mode has been entered.
(check position of loop control
switch SW)
Normal Operation
ERROR OFF
Brief flash
ON
Normal operation
CRC4 error detected
No framing synch found when
Operating on a G.704 network.
POWER ON
OFF
The G-Converter is receiving a
regulated +5V from its power
supply.
The G-Converter is not receiving a
regulated +5V from its power
supply

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Standalone G-Converter
TECHNICAL: 0118 931 2233
Diagnostics
Front Panel LEDs
On the front panel, only the CARRIER LED and POWER should normally be illuminated.
When the G-Converter is disconnected from the network or has lost carrier the CARRIER
LED will extinguish.
Seven Segment Display
The seven segment LED display can reveal the state of the G-Converter. In normal
operation, the display should be steady indicating the N value of the DCE data rate selected.
If the display flashes “Er” then either the G.703 carrier is lost or the framing can not be
recovered from the incoming data stream. This will depend on the G-Converter set up and
the type of network that it is connected to.
If the display flashes “rL”, then a remote loopback has been initiated from a rack mounted G-
Converter card. In this mode the clock and data are suppressed from the DCE connector.
The DCE data being internally looped back to the rack mounted G-Converter card.
If the display flashes “ Fo” this means that an external clock mode has been selected and the
Frequency of the external clock is grossly Out of range.
If the right most decimal point is permanently on, then the G-Converter has either been set to
be a local unit or it is in local loopback (front panel toggle switch set to the left). If this
decimal point is flashing then the G-Coverter is in an external clock mode.
Loopbacks
The loopback switch is located on the front panel. This switch can be disabled by moving
LK12 jumper to position 2-3. In normal operation, the switch is set in a central position, and
the LOOP LED indicator is not illuminated.
When set to local loop back the received data and transmit data of the X.21 interface are
looped. The DCE clock speed will always be determined by the rotary switch settings
regardless if the unit is set for remote operation.
When set to network loop back the transmit data (TXD) of the G.70x interface is looped
directly to the received data (RXD) of the G.70x interface. The DCE clock speed is
determined by the rotary switches in the case of a local unit and by the data being received in
time slot 31 in the case of a remote unit.
It is possible to apply loop backs either at the X.21 side of the converter or the G.703 link
interface side of the converter. Simple functionality tests may be performed on a single G-
Converter whilst disconnected from the Network.

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Standalone G-Converter
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A BERT tester configured, as a DTE capable of generating test patterns should be connected
to the “DCE” port of the G-Converter.
With the link interface disconnected, the LOOP switch on the energised G-Converter set to
Local, the BERT tester will detect the clock being generated by the G-Converter and if the
unit is operating correctly the looped back data should be error free. The clock speed will be
determined by the switch setting.
Ensure that the “DCE” port is providing data rates between 0 and 2048Kbps by selecting 0 to
31 with the front panel switches. Note that during switching of DCE speed errors may be
generated. This is acceptable as long as when the speed setting is in a steady state no errors
are detected.