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Megaplex-2100 Modules

VC-8, VC-16, VC-16A8/16-Channel PCM and16-Channel ADPCM Voice Modules

FEATURES

VC-8 and VC-16 support8 or 16 analog voicechannels using toll-qualityPCM 64 kbps encoding

The following interfaceoptions are available forVC-8 and VC-16 modules: E&M FXS with loop/wink-start

and pulse metering FXO with loop/wink-start

and pulse metering Low cost FXO with

loop-start only

VC-8 and VC-16 enableCaller ID

No-signaling VC-16A moduleprovides ADPCM 32 kbpscompression

A-law or -law companding

Optional in-band signalingwith A-law encodedchannels

Fit into any I/O slot of the

MP-2100/2104 chassis

DESCRIPTION

TheVC-8andVC-16modulesprovide 8 or 16 toll-quality voicechannels. Voice signals aredigitized using PCM, incompliance with ITU-T G.711standards, enabling up to 30 voicechannels to be transmitted over anE1 link, or 24 voice channels overa T1 link.

The high density provided byVC-16 enables a singleMegaplex-2100, equipped with8 x VC-16 modules and2 x ML-2E1 main link modules, tosupport up to 120 PCM channelsover four E1 links. Alternatively,120 PCM channels can besupported over five T1 links, using2 x ML-2T1 and 1 x ML-1T1 mainlink modules.

The smaller Megaplex-2104supports up to 60 PCM channels

over two E1 links, using 4 x VC-16and a 1 x ML-2E1 modules.Alternatively, 48 channels can besupported over two T1 links using3 x VC-16 and a 1 x ML-2T1modules.

Encoding and decoding are in fullcompliance with ITU-Trequirements G.712, G.713 andG.714. Voice channel compandingis selectable for A-law or -law.

Each 64 kbps PCM voice channelis allocated a timeslot on a link in a

DS0 compatible format, permittingvoice channel switching in systemsbased on digital cross-connect(DACS). Each channel can beindependently routed to any link.

Each VC-8/16 voice channelsupports Caller ID by transparentlytransferring the FSK modem tonesbetween the incoming rings. Withthis feature, a customersubscribed to a Caller ID servicecan see theCaller ID of anincoming or waiting callwithany

Caller ID display equipment.

VC-8 and VC-16 are available withthe following interface types:

E&Minterface for supportingdifferent types of E&M signaling:EIA RS-464 Types I, II, III andV (British Telecom SSDC5).Both 2-wire and 4-wire lines aresupported (user-selectable).Typically used for connection of tielines between PBXs (see Figure 1).

FXSinterface supporting both

loop-start and wink-start signalingmethods. FXS interfaces aretypically used for direct connectionto 2-wire telephones in thefollowing loop-start applications:

Off-Premises Extension (OPX),where a local telephone on thePBX can be connected to anoff-premises telephone, by dialingonly the extension numberassigned to the off-premisestelephone (see Figure 2);

Private Line, Automatic

Ringdown application (PLAR)(also referred to as Hot Line),where two telephones areconnected directly via the E1/T1link. When the telephone onone side goes off-hook, theother telephone rings;

Direct connection to 2-wiretelephones in PSTN applications(see Figure 3).

Battery polarity reversal issupported for wink-start signaling,which is used for direct inward

dialing (DID) applications.VC-8/16/FXS also generates12/16 kHz metering pulse forconnection to public payphones(see Figure 4).

FXOinterface supporting bothloop-start and wink-start signalingmethods. Can be used forconnection to PBX extension linesin point-to-point loop-startapplications, opposite acorresponding VC-8/16/FXS at theremote Megaplex, for connectionto the remote extension. Also

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8/16-Channel PCM and 16-Channel ADPCM Voice Modules

VC-8, VC-16, VC-16A

Megaplex-2100 Modules

supports battery polarity reversalfor wink-start signaling and12/16 kHz metering pulse

detection for public payphones.LOOP/FXO is a low-cost version ofthe FXO interface, without reversepolarity or pulse metering. Itsupports loop-start signaling only.

The following signaling transfermodes are selectable for VC-8 andVC-16 modules:

Channel Associated Signaling(CAS) transmitted inTimeslot 16, compatible withITU-T Rec. G.704 (available withE1 links only);

In-band Robbed Bit Multiframe(RBMF) signaling transfer. Thismethod is compatible with ITU-TRec. G.704 and AT&TPub. 43801, and is generallyused with -law companding(available with T1 links only);

Proprietary Robbed Bit Frame(RBF) signaling, which avoids theneed for multiframe

synchronization. RBF allocatesthe least significant bit of eachchannel to its own signalinginformation. This proprietarymethod allows a Megaplexsystem to transmit 31 voicechannels on each E1 link, whenusing G.732N framing;

No signaling channel signalingis not transferred.

To provide feed and ringing signalgeneration voltages, FXS modulesrequire a nominal -48 VDC (-20 to

-54 VDC) source. This power canbe provided either from anappropriate DC-powered chassis,or from an externalRinger-2000/2200 power supplyunit or Ringer-2100R module forAC-powered chassis (see separatedata sheet for information onRingers). The feed and ringgeneration voltages are distributedto the modules via the internalvoltage bus of the chassis.

The E&M modules support the EIARS-464 Type I signaling standardwithout the need for an external

DC power supply. For the othersignaling standard types, theinternal -12 VDC provided by thechassis is sufficient for connectionto most PBX systems.

However, for full supportof TypesII, III and V (BT SSDC5) standards,a -48 VDC power source isrequired (can be supplied asexplained above for FXS modules).

TheVC-16Amodule variantfeatures 32 kbps ADPCMcompression, which enables

allocating a pair of voice channelsto each 64 kbps timeslot. VC-16Ais designed for applicationsrequiring maximum bandwidthutilization but no in-band signaling.It processes only the voice anddoes not transmit any channelassociated signaling information.For E1 links, this results in anadditional timeslot free for carryingvoice and thus 31 PCM (orAPPLICATIONS

E1/T1

MP-2100

PBX

VC-16/E&M VC-16/E&M

MP-2100

PBX

16 Tie Lines 16 Tie Lines

Figure 1. VC-16/E&M Connecting 16 Tie Lines between PBXs

120 Channels

60 Channels

MP-2100

PBX

E1

E1

E1

E1

MP-2104

VC-16/FXSmodules

VC-16/FXOmodules

60 Channels

MP-2104

VC-16/FXSmodules

Figure 2. Multi-point, Off-Premises Extension of 120 PCM Voice Channels using Four E1 Links

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Megaplex-2100 Modules

VC-8, VC-16, VC-16A8/16-Channel PCM and 16-Channel ADPCM Voice Modules

62 ADPCM) channels can besupported rather than theconventional 30 (or 60 ADPCM).

VC-16A enables a singleMegaplex-2100 to support up to160 ADPCM channels over onlythree E1 links (see Figure 5).Alternatively, three T1 links can befully utilized to support144 ADPCM channels by a singleunit.

Gain control is user-selectable forboth the receive and transmitdirection, enabling easy installationin all environments.

All operating parameters areconfigurable via the managementsystem for both the local andremote modules.

Diagnostic features includeloopbacks towards the local userequipment and towards theremote user equipment. Test toneinjection of 1 kHz, 0 dBm0towards the remote or localequipment is also available.

SPECIFICATIONS

Number of Voice ChannelsVC-16, VC-16A: 16VC-8: 8

Voice Encoding TechniquePCM: per ITU-T G.711 andAT&T PUB-43801), -law orA-law

ADPCM (VC-16A only): per ITU-TG.726, -law or A-law

Bandwidth Requirement64 kbps (one timeslot) per enabled

channelVC-16A with ADPCM only:

64 kbps (one timeslot) per pair ofchannels

Analog InterfaceLine type:

E&M, VC-16A: 4-wire or 2-wire(soft-selectable)

FXS, FXO: 2-wireITU-T standards:

2-wire: G.7134-wire: G.712, G.714

Analog ParametersNominal level: 0 dBmNominal impedance: 600

Return loss (ERL) at 300 to 3400 Hz:better than 20 dB

Frequency response (Ref:1020 Hz):0 dB 0.5 dB, at 300 to 3000 Hz0 dB 1.1 dB, at 250 to 3400 Hz

Level adjustment (soft-selectable):E&M: TX: -8 to +5 dBm

RX: -17 to +2 dBmFXS: TX: -5 to +5 dBm

RX: -17 to +1 dBmFXO: TX: -8 to +5 dBm

RX: -17 to +1 dBmVC-16A: TX: -10 to +5 dBm

RX: -17 to +2 dBm

Steps: 0.5 dB (0.15 dB), nominalSignal to total distortion

(G.712, G.713 method 2):-30 to 0 dBm0:

better than 33 dB-45 to +3 dBm0:

better than 22 dBIdle channel noise:

better than -65 dBm0(+20 dBrnc)

Transformer isolation: 1500 VRMS

E1/T1

MP-2100

VC-16/FXS

FXS

Subscriber

Public SwitchedTelephone Network

(PSTN)

1

16

Figure 3. VC-16/FXS Module in Typical PSTN Application

E1/T1

MP-2100

VC-16/FXS

FXS

MP-2100

PBXusing pulse metering

PublicPayphones

PBX

VC-16/FXO

FXO

1

1

16

16

Figure 4. VC-16/FXS and VC-16/FXO Featuring Pulse Metering for Connection to Public Payphones,

and Battery Polarity Reversal for Wink-start Signaling

E1

E1

E1

160 ADPCMChannels

MP-2100

PBX

VC-16Amodules

Network

Figure 5. VC-16A Modules Supporting 160 ADPCM Channels over 3 E1 Links

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4/419882004 RAD Data Communications Ltd. Specifications are subject to change without prior notice.

data communications

www.rad.com

International Headquart24 Raoul Wallenberg StrTel Aviv 69719, IsraelTel: (972) 3-6458181Fax: (972) 3-6498250, 64Email: market@rad.com

U.S. Headquarters900 Corporate DriveMahwah, NJ 07430Tel: (201) 529-1100Toll free: 1-800-444-7234Fax: (201) 529-5777Email: market@radusa.c

Megaplex-2100 Modules

VC-8, VC-16, VC-16A8/16-Channel PCM and 16-Channel ADPCM Voice Modules

764-138-03

VC-8 or 16/E&M InterfaceSignaling method (selectable):

EIA RS-464 Type I;

EIA RS-464 Types II, III, andV (British Telecom SSDC5) using-12 VDC in place of -48 VDCNote:For fullsupport of Types II, III,and V (SSDC5) signaling standards, a-48 VDC supply is required.

Pulse dial distortion: 2 msec max

VC-8 or 16/FXS InterfaceSignaling methods: EIA RS-464

loop-start or wink-startOn-Hook/Off-Hook threshold:(where Vin= -20 to -54 VDC)3V to 80% Vinbetween Tip

and Ring at Off-Hook state,Higher than 83% Vinbetween Tip

and Ring at On-Hook state-48 VDC (nominal) feed currentconsumption:30 mA (10%) per active channel(thusa full VC-16/FXS module consumes480 mA; full VC-8/FXS consumes 240 mA)RAD Ringers support: Ringer-2100R/3000R: up to 40 channels Ringer-2000: up to 100 channels Ringer-2200: up to 200 channels

Ringer:54 VRMS, 22 Hz (10%);Overload protected,

1 second ON, 3 seconds OFFMetering pulse generation:Output frequency:

12 or 16 kHz (2 Hz), selectableOutput level: 1.7 VRMSReverse polarity pulse distortion:6 msec max

VC-8 or 16/FXO InterfaceSignaling methods: EIA RS-464

loop-start or wink-start*DC impedance:Off-Hook:

100at 100 mA feed,

230at 25 mA feedOn-Hook: above 1 MRing detector:20 k@ 20 Hz, 70 VRMSDetection: >20 VRMS, 1725 HzNo detection: