NatComm MODEM SWITCH User manual

MODEM SWITCH
USER GUIDE
For Technical Assistance
Please Phone: [phone]

Page 2 National Communications
PRODUCT DESCRIPTION
MODEM SWITCH is a sophisticated Line Sharing device which is
designed to allow you to connect a Dial Up MODEM to ANY existing
Voice, Fax, Commander/PABX or other Multi-Line telephone system.
It provides you with the ultimate in flexibility, in order to meet a wide
rangeofcustomerapplications.Thisdeviceisdesignedtooperateonan
ordinarysingle telephoneline,orevenwithaPABX/Commanderorother
Multi Line telephone system.
Itprovidesyou withachoice ofTHREEcompletely differentmethodsof
automaticallyreceiveincomingMODEMcallsonanexistingvoiceorfax
line.
DETECTIONOFINCOMINGMODEMCALLINGTONES(1300Hz)
DETECTIONOFINCOMINGDTMFTONESFROMSENDINGMODEM
FAXSTREAMDUETOPERATION
You can receive incoming MODEM calls using any combination of the
above methods, at any time.
ForOutgoingcalls,anEXCLUSIONFACILITYisprovidedtoensurethat
theattachedMODEMdevicecannot‘Barge-In’onatelephonecallorfax
call. Similarly, a telephone or fax call cannot ‘Barge-In’ on a MODEM
transmission. If the telephone or fax line is already in use when the
MODEMdeviceattemptstoinitiateacall,itwillbeblockedfromtheline
and will not be allowed access to the line until the line is free.
YourMODEMSWITCHhasalsobeendesignedforquickandeasyUSER
INSTALLATION direct to ANY TELEPHONE SOCKET, which will take
you just a few minutes (excluding PABX/Commander applications).
PABX/COMMANDERapplicationswill requireprofessionalinstallation.
Please review this user guide thoroughly, select the operating mode
whichbestsuitsyourrequirementsandthenfollowcarefullytheappropriate
operatingandinstallationprocedure.

OPERATION
OUTGOING CALLS (SENDING)
Devices connected to either port of MODEM SWITCH can make an
outgoingcall(SEND)wheneverrequired,providingtheotherdeviceisnot
already using the line. To make an outgoing call (SEND) from either
device,simplyinitiateyourtransmissionasnormal.Therearenospecial
codes required. MODEM SWITCH will automatically detect that the
devicehas gone‘off-hook’todial,andwillconnect itimmediately tothe
telephoneline.
RECEIVING CALLS
MODEM SWITCH distinguishes incoming Modem Calls from other
incoming callsbyansweringallincomingcallsfirst(answersin2rings),
andthenlisteningforashortperiodoftimefor thepresenceofaModem
Calling Tone (1300Hz CNG tone), or a specific DTMF command.
If a Modem calling tone is detected, MODEM SWITCH will RING the
attached Modem device and then connect the incoming Modem call.
If a specific DTMF tone is detected (DTMF 3), MODEM SWITCH will
RINGtheattachedModemdeviceandthenconnecttheincomingModem
call.
If a Modem calling tone or DTMF tone IS NOT CONNECTED, MODEM
SWITCH will realise that the incoming call is not a Modem call and will
RING the OTHER attached device(s) so that they can answer the call.
If the OTHER DEVICE is a Fax Machine, it will answer the call and
connect to receive the incoming fax transmission.
IftheOTHER DEVICE isa Telephone, MultipleTelephonesor a PABX/
CommanderorotherMultiLinetelephonesystem,thenMODEMSWITCH
will ring these devices until the call is answered,or up to 20 times.
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INSTALLATION PROCEDURE
For connection to a FAX LINE
(referto theInstallationDiagramonpage 5)
1.Unplug all equipment from the telephone socket to be used.
2REMOVEthetelephonelinecordfittedtoyourFAXMACHINE(unplug
it from the modular connection on the fax machine).
3.Usingthecableyouhavejustremoved,CONNECTthemodularendof
thiscabletotheTELEPHONELINEINPORToftheMODEMSWITCH.
CONNECT the other end with the Telstra format male plug to your
telephone line socket.
4.UsingoneofthesuppliedModular-Modularlinecords,CONNECTthe
LINEPORToftheFAXDEVICEtotheTELEPHONELINEOUTPORT
ofMODEMSWITCH.
5.Using theothersupplied Modular- Modular linecord, CONNECTthe
LINEPORToftheMODEMDEVICEtotheMODEMDEVICEPORTof
MODEMSWITCH.
6.CONNECT the supplied Power Supply and switch it ON.
7.SET your MODEM DEVICE to it's AUTOMATIC RECEIVE MODE.
ThenSETyourMODEMDEVICEtoANSWERontheFEWESTRINGS
possible. If Fax/Phone/Modem switching settings are provided on
your Modem Device, ensure that they are all DISABLED. Your
MODEM should be set to answer MODEM-DATA calls only.
8.READTHISUSERGUIDEthoroughlytoobtainafullunderstandingof
the operation of this device.

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INSTALLATION DIAGRAM

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INSTALLATION PROCEDURE
For connection to a VOICE LINE
(referto theInstallationDiagramonpage 7)
1.Unplug all equipment from the telephone socket to be used.
2REMOVEthetelephonelinecordsfittedtoyourTELEPHONE(unplug
it from the modular connection on the telephone).
3.Usingthecableyouhavejustremoved,CONNECTthemodularendof
thiscabletotheTELEPHONELINEINPORToftheMODEMSWITCH.
CONNECT the other end with the Telstra format male plug to your
telephone line socket.
4.UsingoneofthesuppliedModular-Modularlinecords,CONNECTthe
TELEPHONEtothePRIMARY DEVICE PORT of MODEM SWITCH.
If you have more than 1 telephone or telephone devices on this line,
they should ALL be connected to the TELEPHONE LINE OUT PORT
ofMODEMSWITCH.Thisprocedurewilllikelyrequirerewiringofyour
telephone by a suitably qualified telephone technician.
5.Using theothersuppliedModular-Modularlinecord,CONNECT the
LINEPORToftheMODEMDEVICEtotheMODEMDEVICEPORTof
MODEMSWITCH.
6.CONNECT the supplied Power Supply and switch it ON.
7.SET your MODEM DEVICE to it's AUTOMATIC RECEIVE MODE.
ThenSETyourMODEMDEVICEtoANSWERontheFEWESTRINGS
possible. If Fax/Phone/Modem switching settings are provided on
your Modem Device, ensure that they are all DISABLED. Your
MODEM should be set to answer MODEM-DATA calls only.
8.READTHISUSERGUIDEthoroughlytoobtainafullunderstandingof
the operation of this device.

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INSTALLATION DIAGRAM

Page 8 National Communications
INSTALLATION PROCEDURE
For connection to a PABX LINE
or other Multi-Line System
1. MODEM SWITCH can be fitted to one specific line of a Commander
or PABX type system. This must be done by a suitably qualified
telephone technician. In this situation :
The incoming telephone line, prior to the system controller should
be connected to the TELEPHONE LINE IN port of MODEM SWITCH.
The PRIMARY DEVICE port should be connected to the system
controller.
The TELEPHONE LINE OUT PORT of the MODEM DEVICE should
then be connected to the MODEM DEVICE PORT of MODEM
SWITCH.
Once fitted, the system will operate exactly as described previously,
for operation on the selected line.
2.CONNECT the supplied Power Supply and switch it ON.
3.SET your MODEM DEVICE to it's AUTOMATIC RECEIVE MODE.
ThenSETyourMODEMDEVICEtoANSWERontheFEWESTRINGS
possible. If Fax/Phone/Modem switching settings are provided on
your Modem Device, ensure that they are all DISABLED. Your
MODEM should be set to answer MODEM-DATA calls only.
4.READTHISUSERGUIDEthoroughlytoobtainafullunderstandingof
the operation of this device.

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REQUIREMENTS FOR THE
CALLING MODEM DEVICE(S)
MODEM SWITCH distinguishes incoming Modem Calls from other
incoming callsbyansweringallincomingcallsfirst(answersin2rings),
andthenlisteningforashortperiodoftimefor thepresenceofaModem
Calling Tone (1300Hz CNG tone), or a specific DTMF command.
Modem devices generate a 1300Hz Calling Tone when dialing out to
another site. This calling tone is designed to allow the remote site to
immediately recognise that the incoming call is from a Modem.
Most Modem devices generate this 1300Hz Calling Tone as a default
condition.However,someModemsmayhavethisfacility DISABLED.It
willbenecessaryforthisModemdevicetohaveCallingTonesENABLED.
This is usually done in the Sending Menu of the dialing software.
ForexperiencedModemusers,youmaywishtouseashortcutcommand
to ENABLE Calling Tones. This shortcut involves entering a ^ symbol
anywhereinthedialingstringcommand,orinitialisationstringcommand
for the Modem. Some Modem devices will also generate the 1300Hz
CallingTonewhen youtoentera^attheendofthephonenumber.The
alternativeisto add additional DTMF digitstothe number to bedialled,
as per the details on the next page (DTMF Access Mode), to advise to
the remote site that the call is to connect to a Modem.
A very small number of early model Modem devices CANNOT be set to
generate the 1300Hz Calling Tone. In this situation, these Modem
devices will need to send additional DTMF digits to the number to be
dialled , as per the details on the next page (DTMF Access Mode), in
orderto adviseto theremote sitethat thecall istoconnecttoaModem.

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DTMF ACCESS MODE
Some calling Modem devices may have the 1300Hz Calling Tone
disabled, or it may not be available. In these situations, the remote
Modem user should add a sequence of extra digits to the end of the
telephone number that the MODEM SWITCH is calling.
For example :
If the Telephone Number to be dialed is :[phone]
Your Modem Number will be :[phone],,3,3,3,3,3,3
This extended number can be entered into the callers phone book, just
like any other Modem number and then automatically recalled and
dialled when required. It is a once only setting. These extra digits
instructthecallingModemtoDIALaseriesofDTMF3commands,after
the normal number has been dialled.
Each (,) represents a pause time of 2 seconds. This sequence will
ensurethatthe(3)commandissentatregularintervalsafterdiallingfor
a period of up to 14 seconds.
By doing so, at least one 3 command will be detected by MODEM
SWITCH after the line has been answered, to instruct the MODEM
SWITCH to redirect the incoming Modem call to the attached Modem.
ADVANCEDUSERINFORMATION-Thenumberof'3''stransmittedcan
be increased or decreased to suit, but they should be transmitted for a
sufficient period of time to ensure that they extend up to or beyond the
timeatwhichtheMODEMSWITCH willanswerthecall.Alternativelythe
pause time of each (,) can be increased beyond 2 seconds (up to a
maximumof4seconds)bychangingthesettingsoftheS8registerofthe
sendingModem.
Oncethefirst(3)hasbeendetectedbyMODEMSWITCH,itwillwaituntil
allsubsequent(3)commandsarecomplete,beforeringingtheattached
Modem.This precautionwillensure thatthe(3) commandstransmitted
do not interfere with the Modem handshake process.