Allied Telesis AT-MR820TR User Manual

CentreCOM

®

AT-MR420TR AT-MR820TR

Multiport Micro Repeaters

Installation Guide

PN 613-10625-00 Rev A

Copyright 1997 Allied Telesyn International Corp.
All rights reserved. No part of this publication may be reproduced without prior written
permission from Allied Telesyn International Corp.

Allied Telesyn International Corp. reserves the right to make changes in specifications and
other information contained in this document without prior written notice. The information
provided herein is subject to change without notice. In no event shall Allied Telesyn
International Corp. be liable for any incidental, special, indirect, or consequential damages
whatsoever, including but not limited to lost profits, arising out of or related to this manual
or the information contained herein, even if Allied Telesyn International Corp. has been
advised of, known, or should have known, the possibility of such damages.

Trademarks: Ethernet is a registered trademark of Xerox Corporation. UNIX is a
registered trademark of UNIX System Laboratories. Novell and NetWare are registered
trademarks of Novell, Inc. Microsoft and MS-DOS are registered trademarks and LAN
Manager and Windows for Workgroups are trademarks of Microsoft Corporation. 3Com is a
registered trademark of 3Com. PC-NFS is a trademark of Sun Microsystems, Inc. PC/TCP
is a registered trademark of FTP Software, Inc. DECnet is a registered trademark of
Digital Equipment Corporation.

All company names, logos, and product designations that are trademarks or registered
trademarks are the property of their owners.

Electrical Safety and Installation Requirements

U.S. Federal Communications Commission

RADIATED ENERGY

Note: This equipment has been tested and found to comply with the limits for a
Class A digital device pursuant to Part 15 of the FCC Rules. These limits are
designed to provide reasonable protection against harmful interference when
the equipment is operated in a commercial environment. This equipment
generates, uses, and can radiate radio frequency energy and, if not installed and
used in accordance with the instruction manual, may cause harmful
interference to radio communications. Operation of this equipment in a
residential area is likely to cause harmful interference in which case the user
will be required to correct the interference at his own expense.

Note: Modifications or changes not expressly approved by the manufacturer or
the FCC can void your right to operate this equipment.

Canadian Department of Communications

This Class A digital apparatus meets all requirements of the Canadian
Interference-Causing Equipment Regulations.

Cet appariel numérique de la classe A respecte toutes les exigences du
Règlement sur le matériel brouilleur du Canada.

STANDARDS:
RFI Emission
WARNING:

in which case the user may be required to take adequate measures.

Immunity

These products have been safety tested by UL to Standard UL 1950, CSA to CSA
950 and by TUV to EN60950.

SAFETY
ELECTRICAL NOTICES

WARNING: ELECTRIC SHOCK HAZARD
To prevent ELECTRIC shock, do not remove cover. No user-serviceable parts
inside. This unit contains HAZARDOUS VOLTAGES and should only be opened by
a trained and qualified technician. To avoid the possibility of ELECTRIC SHOCK,
disconnect electric power to the product before connecting or disconnecting the LAN
cables.

LIGHTNING DANGER
DANGER

LIGHTNING ACTIVITY.

CAUTION

ENERGISE EQUIPMENT, disconnect the power cord.

This product meets the following standards

: EN55022 Class A

In a domestic environment this product may cause radio interference

: EN50082-1

: DO NOT WORK on equipment or CABLES during periods of

: POWER CORD IS USED AS A DISCONNECTION DEVICE. TO DE-

iii

INSTALLATION
ELECTRICAL

This product will automatically adjust to any voltage between the ranges shown on
the label.

ELECTRICAL—TYPE CLASS 1 EQUIPMENT

THIS EQUIPMENT MUST BE EARTHED. Power plug must be connected to a
properly wired earth ground socket outlet. An improperly wired socket outlet could
place hazardous voltages on accessible metal parts.

ELECTRICAL

Use power cord, maximum 4.5 meters long, rated 6 amp minimum, 250V, made of
HAR cordage molded IEC 320 connector on one end and on the other end a plug
approved by the country of end use.

MOUNTING INSTRUCTIONS
CAUTION

VERTICAL MOUNTING must not be done without the use of an Allied Telesyn
vertical mount chassis designed for this purpose.

CAUTION

ambient air for cooling.

CAUTION

vertical mounting chassis is being used.

OPERATING TEMPERATURE

This product is designed for a maximum ambient temperature of 40° C.

ALL COUNTRIES:

Electrical Codes.

—AUTO VOLTAGE ADJUSTMENT

—CORD NOTICE

: These models are designed for operation in the HORIZONTAL position.

: Air vents must not be blocked and must have free access to the room

: DO NOT detach rubber feet from the product unless an Allied Telesyn

Install product in accordance with local and National

NORMEN:
Hochfrequenzstörung:
WARNUNG:

hervorrufen. In diesem Fall müßte der Anwender angemessene Gegenmaßnahmen
ergreifen.

Störsicherheit:

Die Sicherheitsprüfung dieser Produkte wurde von Underwriters Laboratories Inc.
gemäß Norm 1950, CSA nach CSA 950 und gemäß TÜV nach EN60950
durchgeführt.

SICHERHEIT
ACHTUNG:
Das Gehäuse nicht öffnen. Das Gerät enthält keine vom Benutzer wartbaren Teile.
Das Gerät steht unter Hochspannung und darf nur von qualifiziertem technischem
Personal geöffnet werden. Vor Anschluß der LAN-Kabel, Gerät vom Netz trennen.

GEFAHR DURCH BLITZSCHLAG
GEFAHR

ausführen.

VORSICHT

STROMVERSORGUNG. ZUR TRENNUNG VOM NETZ, KABEL AUS DER
STECKDOSE ZIEHEN.

INSTALLATION
AUTOMATISCHE SPANNUNGSEINSTELLUNG

Dieses Gerät stellt sich automatisch auf die auf dem Etikett aufgeführten
Spannungswerte ein.

Dieses Produkt erfüllt die Anforderungen der nachfolgenden Normen.

EN55022 Klasse A

Bei Verwendung zu Hause kann dieses Produkt Funkstörungen

EN50082-1

GEFÄHRLICHE SPANNUNG

: Keine Arbeiten am Gerät oder an den Kabeln während eines Gewitters

: DAS NETZKABEL DIENT ZUM TRENNEN DER

iv

KLASSE 1 GERÄTE

DIESE GERÄTE MÜSSEN GEERDET SEIN. Der Netzstecker darf nur mit einer
vorschriftsmäßig geerdeten Steckdose verbunden werden. Ein
unvorschriftsmäßiger Anschluß kann das Metallgehäuseteile unter gefährliche
elektrische Spannungen setzen.

NETZKABEL

Das Netzkabel sollte eine maximale Länge von 4,5 Metern, einen Nennwert von
mindestens 6 A und 250 V haben, aus HAR-Material hergestellt und mit einer
gepreßten, IEC 320 entsprechenden, Anschlußverbindung an einem Ende, und am
anderen Ende mit einem im Land des Endverbrauchers geprüften Stecker
ausgestattet sein.

MONTAGEANWEISUNGEN
VORSICHT

worden. Das Gerät darf NICHT OHNE Gebrauch eines dafür entworfenen Allied
Telesyn-Vertikalmontagegestells in VERTIKALER POSITION montiert werden.

VORSICHT

zum Kühlen freien Zugang zur Raumluft haben.

VORSICHT

Allied Telesyn-Vertikalmontagegestells.

BETRIEBSTEMPERATUR

Dieses Produkt wurde für den Betrieb in einer Umgebungstemperatur von nicht
mehr als 40˚ C entworfen.

ALLE LÄNDER:

Vorschriften entsprechen.

: Diese Modelle sind für Betrieb in horizontaler Position entworfen

: Die Entlüftungsöffnungen dürfen nicht versperrt sein und müssen

: Die Gummifüße NICHT ENTFERNEN, außer bei Gebrauch des

Installation muß örtlichen und nationalen elektrischen

Radiofrekvens forstyrrelsesemission
ADVARSEL:

Bliver det tilfældet, påkræves brugeren muligvis at tage tilstrækkelige
foranstaltninger.

Immunitet:

Disse produkter er blevet sikkerhedstestet af UL til Standard 1950, CSA til CSA
950 og af TUV til EN60950.

SIKKERHED
ELEKTRISKE FORHOLDSREGLER
ADVARSEL: RISIKO FOR ELEKTRISK STØD

For at forebygge ELEKTRISK stød, undlad at åbne apparatet. Der er ingen indre
dele, der kan repareres af brugeren. Denne enhed indeholder LIVSFARLIGE
STRØMSPÆNDINGER og bør kun åbnes af en uddannet og kvalificeret tekniker.
For at undgå risiko for ELEKTRISK STØD, afbrydes den elektriske strøm til
produktet, før LAN-kablerne monteres eller afmonteres.

FARE UNDER UVEJR

FARE: UNDLAD at arbejde på udstyr eller KABLER i perioder med
LYNAKTIVITET.

ADVARSEL

STRØMMEN. SKAL STRØMMEN TIL APPARATET AFBRYDES, tages
ledningen ud af stikket.

INSTALLATION
ELEKTRISK

Dette apparat vil automatisk tilpasse sig enhver spænding indenfor de værdier, der
er angivet på etiketten.

I et hjemligt miljø kunne dette produkt forårsage radio forstyrrelse.

EN50082-1

: DEN STRØMFØRENDE LEDNING BRUGES TIL AT AFBRYDE

—AUTOMATISK SPÆNDINGSREGULERING

: EN55022 Klasse A

v

ELEKTRISK—KLASSE 1-UDSTYR

DETTE UDSTYR KRÆVER JORDFORBINDELSE. Stikket skal være forbundet
med en korrekt installeret jordforbunden stikkontakt. En ukorrekt installeret
stikkontakt kan sætte livsfarlig spænding til tilgængelige metaldele.

ELEKTRISK

Anvend ledning af maksimum 4,5 meters længde, med en kapacitet på minimum 6
amp., 250 v, bestående af en IEC 320 connector med indstøbt HAR ledning i den
ene ende og et stik i den anden ende godkendt der er af myndighederne i
brugerlandet.

INSTRUKTIONER FOR OPSTILLING
ADVARSEL

(vandret). VERTIKAL OPSTILLING (lodret) må IKKE FORETAGES uden brug af
et Allied Telesyn vertikalt monteringsstel konstrueret til dette formål.

ADVARSEL

omgivende luft i rummet for afkøling.

ADVARSEL

anvendes et Allied Telesyn vertikalt monteringsstel.

BETJENINGSTEMPERATUR

Dette apparat er konstrueret til en omgivende temperatur på maksimum 40 grader
C.

ALLE LANDE:

national lovgivning for elektriske installationer.

—LEDNING

: Disse modeller er konstrueret til at betjenes i HORISONTAL position

: Ventilationsåbninger må ikke blokeres og skal have fri adgang til den

: UNDLAD at fjerne gummisoklerne fra apparatet, med mindre der

Installation af produktet skal ske i overensstemmelse med lokal og

RFI Emissie:
WAARSCHUWING:

welk geval de gebruiker verplicht kan worden om gepaste maatregelen te nemen.

Immuniteit:

De veiligheid van deze produkten is door UL getest volgens norm 1950, CSA tot
CSA 950 en door TUV volgens EN60950.

VEILIGHEID
WAARSCHUWINGEN MET BETREKKING TOT ELEKTRICITEIT
WAARSCHUWING

Gelieve het deksel niet te verwijderen, teneinde ELEKTRISCHE schokken te
voorkomen. Binnenin bevinden zich geen onderdelen die door de gebruiker kunnen
worden onderhouden. Dit toestel staat onder GEVAARLIJKE SPANNING en mag
alleen worden geopend door een daartoe opgeleide en bevoegde technicus. Om het
gevaar op ELEKTRISCHE SCHOKKEN te vermijden, moet u het toestel van de
stroombron ontkoppelen alvorens de LAN-kabels te koppelen of ontkoppelen.

GEVAAR VOOR BLIKSEMINSLAG
GEVAAR

WAARSCHUWING

STROOMKABEL TE ONTKOPPELEN. OM HET TOESTEL STROOMLOOS TE
MAKEN: de stroomkabel ontkoppelen.

INSTALLATIE
ELEKTRISCH

Dit toestel past zich automatisch aan elke spanning aan, tussen de waarden op het
label vermeld.

ELEKTRISCHE—TOESTELLEN VAN KLASSE 1

DIT TOESTEL MOET GEAARD WORDEN. De stekker moet aangesloten zijn op
een juist geaarde contactdoos. Een onjuist geaarde contactdoos kan de metalen
onderdelen waarmee de gebruiker eventueel in aanraking komt onder gevaarlijke
spanning stellen.

EN55022 Klasse A

Binnenshuis kan dit product radiostoring veroorzaken, in

EN50082-1

: GEVAAR VOOR ELEKTRISCHE SCHOKKEN

: NIET aan toestellen of KABELS WERKEN bij BLIKSEM.

: HET TOESTEL WORDT UITGESCHAKELD DOOR DE

—AUTOMATISCHE AANPASSING VAN DE SPANNING

vi

ELEKTRISCHE

Gebruik een elektrisch snoer, maximum 4,5 meter lang, berekend voor ten minste 6
ampère, 250 V, uit HAR vervaardigd, met aan het ene uiteinde een gevormde IEC
320 stekker en aan het andere uiteinde een stekker die goedgekeurd is door het
land waar het toestel zal worden gebruikt.

MONTAGE-INSTRUCTIES
WAARSCHUWING

HORIZONTALE stand.
VERTICALE MONTAGE mag NIET UITGEVOERD WORDEN, tenzij een daartoe
speciaal ontworpen Allied Telesyn chassis voor verticale montage wordt gebruikt.

WAARSCHUWING

omgevingslucht ongehinderd toelaten voor afkoeling.

WAARSCHUWING

behalve wanneer een chassis voor vertikale montage van Allied Telesyn wordt
gebruikt.

BEDRIJFSTEMPERATUUR

De omgevingstemperatuur voor dit produkt mag niet meer bedragen dan 40 graden
Celsius.

ALLE LANDEN:

elektrische voorschriften.

—SNOEREN

: Deze modellen zijn ontworpen om te werken in

: De ventilatiegaten mogen niet worden gesperd en moeten de

: De rubberen voetjes NIET van het produkt LOSMAKEN

het toestel installeren overeenkomstig de lokale en nationale

NORMES:
Emission d'interférences radioélectriques:
MISE EN GARDE:

des interférences radioélectriques. Auquel cas, l'utilisateur devra prendre les
mesures adéquates.

Immunité:

La sécurité de ces matériels a été testée par UL conformément à la norme UL 1950,
CSA à CSA 950 et par TUV conformément à la norme EN60950.

SECURITE
INFORMATION SUR L’ELECTRICITE
AVERTISSEMENT: DANGER D’ELECTROCUTION

Pour empêcher les dangers d’ELECTROCUTION, ne pas enlever le couvercle.
L’équipement ne contient aucun élément réparable par l’utilisateur. Cet appareil
comprend des TENSIONS DANGEREUSES et ne doit être ouvert que par un
technicien dûment qualifié. Pour éviter tout risque d’ELECTROCUTION,
débrancher l’appareil de la prise de courant avant de connecter ou de déconnecter
les câbles LAN.

DANGER DE FOUDRE
DANGER

d’activité orageuse.

ATTENTION

POUR COUPER L’ALIMENTATION DE L’APPAREIL, débranchez le cordon.

INSTALLATION
ELECTRICITE—REGLAGE DE TENSION AUTOMATIQUE

Ce produit peut s’ajuster automatiquement sur n’importe quelle tension comprise
dans la plage indiquée sur le label.

ELECTRICITE—EQUIPEMENT DE CLASSE 1

CET APPAREIL DOIT ETRE MIS A LA TERRE. La prise de courant doit être
branchée dans une prise femelle correctement mise à la terre. Sinon, des tensions
dangereuses risqueraient d’atteindre les pièces métalliques accessibles à
l’utilisateur.

ce produit est conforme aux normes de suivantes :

EN55022 Classe A

dans un environnement domestique, ce produit peut provoquer

EN50082 - 1

: NE PAS MANIER l’équipement ou les CABLES pendant les périodes

: LE CORDON D’ALIMENTATION SERT DE MISE HORS CIRCUIT

vii

ELECTRICITE

Utiliser un cordon secteur de 4,5 mètres de long maximum, calibré à 6 ampères
minimum, 250V, et fabriqué en câblage HAR avec connecteur IEC 32C moulé à une
extrémité et à l’autre extrémité, une prise de courant mâle répondant aux normes
du pays d’utilisation.

INSTRUCTIONS DE MONTAGE
ATTENTION

L’appareil NE DOIT PAS être utilisé en MONTAGE VERTICAL sans employer un
châssis de montage vertical Allied Telesyn conçu à cet effet.

ATTENTION

ambiant de circuler librement pour le refroidissement.

ATTENTION

d’utiliser un châssis de montage vertical Allied Telesyn.

TEMPERATURE DE FONCTIONNEMENT

Ce produit est capable de tolérer une température ambiante maximum de 40 degrés
Celsius

POUR TOUS PAYS:

nationales et locales.

—INFORMATION SUR LE CORDON

: Ces modèles sont destiné à fonctionner en position horizontale.

: Ne pas bloquer les fentes d’aération, ce qui empêcherait l’air

: NE PAS ôter les pattes d’attache en caoutchouc du produit, à moins

Installer le produit conformément aux normes électriques

Radioaaltojen häirintä:
VAROITUS:

missä tapauksessa laitteen käyttäjän on mahdollisesti ryhdyttävä tarpeellisiin
toimenpiteisiin.

Kestävyys:

UL on turvatestannut nämä tuotteet Standard 1950 mukaisesti, CSA standardin
CSA 950 mukaisesti ja TUV standardin EN60950 mukaisesti.

TURVALLISUUS
SÄHKÖÖN LIITTYVIÄ HUOMAUTUKSIA
VAROITUS: SÄHKÖISKUVAARA

Estääksesi SÄHKÖISKUN älä poista kantta. Sisällä ei ole käyttäjän huollettavissa
olevia osia. Tämä laite sisältää VAARALLISIA JÄNNITTEITÄ ja sen voi avata vain
koulutettu ja pätevä teknikko. Välttääksesi SÄHKÖISKUN mahdollisuuden
katkaise sähkövirta tuotteeseen ennen kuin liität tai irrotat paikallisverkon (LAN)
kaapelit.

SALAMANISKUVAARA
HENGENVAARA

SALAMOINNIN AIKANA.

HUOMAUTUS

VIRTA KATKAISTAAN irrottamalla virtajohto.

ASENNUS
SÄHKÖ—AUTOMAATTINEN JÄNNITTEENSÄÄTÖ

Tämä tuote säätää automaattisesti mihin tahansa jännitteeseen ohjetarrassa
annettujen arvojen välillä.

SÄHKÖ—TYYPPILUOKAN 1 LAITTEET

TÄMÄ LAITE TÄYTYY MAADOITTAA. Pistoke täytyy liittää kunnollisesti
maadoitettuun pistorasiaan. Virheellisesti johdotettu pistorasia voi altistaa
metalliosat vaarallisille jännitteille.

SÄHKÖ—JOHTOON LIITTYVÄ HUOMAUTUS

Käytä seuraavanlaista virtajohtoa: maksimipituus 4,5 metriä, minimiteho 6
ampeeria, 250 V, valmistettu HAR-johdostosta, muovattu IEC 320 -liitin toisessa
päässä ja käyttömaassa hyväksytty pistoke toisessa päässä.

Kotiolosuhteissa tämä laite voi aiheuttaa radioaaltojen häiröitä,

EN50082-1

: VIRTAJOHTOA KÄYTETÄÄN VIRRANKATKAISULAITTEENA.

EN55022 Luokka A

: ÄLÄ TYÖSKENTELE laitteiden tai KAAPELEIDEN KANSSA

viii

ASENNUSSOHJEET
HUOMAUTUS

PYSTYASENNUSTA EI SAA TEHDÄ ilman Allied Telesyn -pystykiinnitysalustaa,
joka on suunniteltu tähän tarkoitukseen.

HUOMAUTUS

ympäröivään huoneilmaan, jotta ilmanvaihto tapahtuisi.

HUOMAUTUS

pystykiinnitysalusta ole käytössä.

KÄYTTÖLÄMPÖTILA

Tämä tuote on suunniteltu ympäröivän ilman maksimilämpötilalle 40° C.

KAIKKI MAAT:

sähköturvallisuusmääräysten mukaisesti.

: Nämä mallit on suunniteltu käytettäviksi VAAKA-asennossa.

: Ilmavaihtoreikiä ei pidä tukkia ja niillä täytyy olla vapaa yhteys

: ÄLÄ irroita kumijalkoja tuotteesta, ellei Allied Telesyn-

Asenna tuote paikallisten ja kansallisten

Emissione RFI (interferenza di radiofrequenza):
AVVERTENZA:

interferenza. In questo caso potrebbe richiedersi all'utente di prendere gli adeguati
provvedimenti.

Immunità:

Questi prodotti sono stati sottoposti a collaudi di sicurezza dai seguenti enti: dalla
UL in conformità allo standard 1950, dalla CSA in conformità allo standard CSA
950 e dal TUV in conformità allo standard EN60950.

NORME DI SICUREZZA
AVVERTENZE ELETTRICHE
ATTENZIONE: PERICOLO DI SCOSSE ELETTRICHE

Per evitare SCOSSE ELETTRICHE non asportare il coperchio. Le componenti
interne non sono riparabili dall’utente. Questa unità ha TENSIONI PERICOLOSE
e va aperta solamente da un tecnico specializzato e qualificato. Per evitare ogni
possibilità di SCOSSE ELETTRICHE, interrompere l’alimentazione del dispositivo
prima di collegare o staccare i cavi LAN.

PERICOLO DI FULMINI
PERICOLO

PRECIPITAZIONI TEMPORALESCHE.

ATTENZIONE

DI DISATTIVAZIONE.
PER TOGLIERE LA CORRENTE AL DISPOSITIVO staccare il cavo di
alimentazione.

INSTALLAZIONE
ELETTRICITÀ

Questo prodotto regolerà automaticamente la tensione ad un valore compreso nella
gamma indicata sull’etichetta.

ELETTRICITÀ

QUESTO DISPOSITIVO DEVE AVERE LA MESSA A TERRA. La spina deve
essere inserita in una presa di corrente specificamente dotata di messa a terra. Una
presa non cablata in maniera corretta rischia di scaricare una tensione pericolosa
su parti metalliche accessibili.

ELETTRICITÀ

Usare un cavo della lunghezza massima di metri 4,5, con capacità minima di 6 A,
250 V, di filo HAR, dotato di connettore stampato IEC 320 ad un’estremità e di
spina approvata dal paese di destinazione all’altra.

in ambiente domestico questo prodotto potrebbe causare radio

EN50082-1

: NON LAVORARE sul dispositivo o sui CAVI durante

: IL CAVO DI ALIMENTAZIONE È USATO COME DISPOSITIVO

—REGOLAZIONE AUTOMATICA DELLA TENSIONE

—DISPOSITIVI DI CLASSE 1

—AVVERTENZA SUL CAVO

EN55022 Classe A

ix

ISTRUZIONI PER IL MONTAGGIO
ATTENZIONE

ORIZZONTALE. NON È POSSIBILE EFFETTUARE IL MONTAGGIO
VERTICALE senza utilizzare l’apposito telaio per il montaggio verticale Allied
Telesyn.

ATTENZIONE

ricircolo dell’aria ambiente per il raffreddamento.

ATTENZIONE

utilizzi il telaio Allied Telesyn per il montaggio verticale.

TEMPERATURA DI FUNZIONAMENTO

Questo prodotto è concepito per una temperatura ambientale massima di 40 gradi
centigradi.

TUTTI I PAESI:

elettriche nazionali.

: questi modelli sono concepiti per il funzionamento in posizione

: le prese d’aria non vanno ostruite e devono consentire il libero

: NON staccare il piedino in gomma dal prodotto tranne qualora si

installare il prodotto in conformità alle vigenti normative

RFI stråling:
ADVARSEL:

forårsake radioforstyrrelse. Hvis dette skjer, må brukeren ta de nødvendige
forholdsregler.

Immunitet:

Disse produktene er blitt sikkerhetstestet av UL i forhold til standard 1950, CSA i
forhold til CSA 950, og av TUV i forhold til EN60950.

SIKKERHET
ELEKTRISKE MEDDELELSE
ADVARSEL: FARE FOR ELEKTRISK SJOKK

For å unngå ELEKTRISK sjokk, må dekslet ikke tas av. Det finnes ingen deler som
du kan bruke på innsiden. Denne enheten inneholder FARLIGE SPENNING, og
må kun åpnes av en opplært, kvalifisert tekniker. For å unngå muligheten av
ELEKTRISK SJOKK, må den elektriske strømmen til produktet være av når du
slår LAN-ledninger av og på.

FARE FOR LYNANTENNELSE
FARE

gang.

FORSIKTIG

DU VIL DEAKTIVISERE UTSTYRET, må du fjerne strømledningen.

INSTALLASJON
ELEKTRISK

Dette produktet vil automatisk bli tilpasset hvilken som helst strøminnstilling i de
områdene som vises på etiketten.

ELEKTRISKE—TYPE 1. KLASSE UTSTYR
DETTE UTSTYRET MÅ JORDES

korrekt jordet grunnstøpselkontakt. En støpselkontakt som ikke er jordet på rett
måte, kan tilføre farlig spenning til lett tilgjengelige metalldeler.

ELEKTRISKE

Bruk en strømledning av maksimal størrelse 4,5 m i lengde, vurdert for minst av 6
amp, 250V, fremstilt av HAR ledning IEC 320 koplingsstykke på den ene kanten og
på den andre kanten en plugg som har blitt godkjent i det landet hvor den siste
brukeren befinner seg.

BRUKSANVISNINGER FOR MONTERING
FORSIKTIG

VERTIKAL MONTERING må IKKE UTFØRES uten bruk av et Allied Telesyn
vertikal monteringschassis som er spesiallaget til dette formål.

EN55022 Klasse A

Hvis dette produktet benyttes til privat bruk, kan produktet

EN50082-1

: MÅ IKKE BRUKES på utstyr eller ledninger mens LYN-AKTIVITET er i

: STRØMLEDNINGEN BRUKES TIL Å SLÅ APPARATET AV. HVIS

—AUTO SPENNINGSTILPASSING

. Strømkontakten må være tilkoplet en

—MEDDELELSE OM LEDNINGER

: Disse modellene er beregnet til bruk i HORISONTAL stilling.

x

FORSIKTIG: MEKANISK LASTNING

utføres på slik måte at ingen farlige situasjoner oppstår som en følge av ujevn
lastning.

FORSIKTIG

romtemperatur for avkjøling.

FORSIKTIG

Telesyn vertikal monteringschassis er i bruk.

DRIFTSTEMPERATUR

Dette produktet har blitt fremstilt til bruk med maksimum romtemperatur på 40
grader celsius.

ALLE LAND:

elektriske koder.

: Luftventilene må ikke blokkeres og må ha fri tilgang til luft med

: Gummiføttene må IKKE fjernes fra produktet med mindre en Allied

Produktet må installeres i samsvar med de lokale og nasjonale

Installering av utstyret på hyllen må

Emissão de interferência de radiofrequência:
AVISO:

Num ambiente doméstico este produto pode causar interferência na
radiorrecepção e, neste caso, pode ser necessário que o utente tome as medidas
adequadas.

Imunidade:

Estes produtos foram testados pela UL quanto a aspectos de segurança no Padrão
1950, CSA a CSA 950, e pela TUV no EN60950.

SEGURANÇA
AVISOS SOBRE CARACTERÍSTICAS ELÉTRICAS
ATENÇÃO:

Para evitar CHOQUE ELÉTRICO, não retire a tampa. Não contém peças que
possam ser consertadas pelo usuário. Este aparelho contém VOLTAGENS
PERIGOSAS e só deve ser aberto por um técnico qualificado e treinado. Para evitar
a possibilidade de CHOQUE ELÉTRICO, desconecte o aparelho da fonte de energia
elétrica antes de conectar e desconectar os cabos da LAN.

PERIGO DE CHOQUE CAUSADO POR RAIO
PERIGO:

suscetíveis de QUEDAS DE RAIO.

CUIDADO

DISPOSITIVO DE DESCONEXÃO.
PARA DESELETRIFICAR O EQUIPAMENTO desconecte o cabo de alimentação.

INSTALAÇÃO
ELÉTRICO

Este produto ajustar-se-á automaticamente a qualquer voltagem que esteja dentro
dos limites indicados no rótulo.

ELÉTRICO—EQUIPAMENTOS DO TIPO CLASSE 1

DEVE SER FEITA LIGAÇÃO DE FIO TERRA PARA ESTE EQUIPAMENTO. O
plugue deve ser conectado a uma tomada com ligação de fio terra. Tomadas sem
ligação de fio terra podem transmitir voltagens perigosas a peças metálicas
expostas.

ELÉTRICO

Use cabo de alimentação com comprimento máximo de 4, 5 metros, com uma
capacidade mínima de 6 amp e 250 V, fabricado de material para cabo HAR com
conector moldado IEC 320 em uma extremidade e, na outra extremidade, um
plugue aprovado para uso no país em questão .

EN50082-1

PERIGO DE CHOQUE ELÉTRICO

NÃO TRABALHE no equipamento ou nos CABOS durante períodos

: O CABO DE ALIMENTAÇÃO É UTILIZADO COMO UM

—AJUSTE AUTOMÁTICO DE VOLTAGEM

—AVISO SOBRE O CABO DE ALIMENTAÇÃO

EN55022 Classe A

xi

INSTRUÇÕES DE INSTALAÇÃO
CUIDADO: Este modelos foram projetados para funcionar na posição

HORIZONTAL. NÃO DEVE SER EFETUADA INSTALAÇÃO VERTICAL sem o
uso de um chassis de montagem vertical Allied Telesyn projetado para este fim
específico.

CUIDADO: CARREGAMENTO - O equipamento deverá ser montado no suporte
de montagem de forma a não causar perigo devido a carregamento não-uniforme.

CUIDADO: As entradas de ar não devem ser bloqueadas e devem ter acesso livre
ao ar ambiente para arrefecimento adequado do aparelho.

CUIDADO: NÃO RETIRE os calços de borracha do produto a menos que esteja
sendo usado um chassis de montagem vertical Allied Telesyn.

TEMPERATURA DE FUNCIONAMENTO

Este produto foi projetado para uma temperatura ambiente máxima de 40 graus
centígrados.

TODOS OS PAÍSES: Instale o produto de acordo com as normas federais e locais
para instalações elétricas.

Emisión RFI: EN55022 Clase A
ADVERTENCIA: en un entorno doméstico, este producto puede causar

radiointerferencias, en cuyo caso, puede requerirse del usuario que tome las
medidas que sean convenientes al respecto.

Inmunidad: EN50082-1
La seguridad de estos productos ha sido probada por UL conforme con la Norma

1950, CSA a CSA 950, y por TUV conforme con EN60950.

SEGURIDAD
AVISOS ELECTRICOS
ADVERTENCIA: PELIGRO DE ELECTROCHOQUE

Para evitar un ELECTROCHOQUE, no quite la tapa. No hay ningún componente
en el interior al cual puede prestar servicio el usuario. Esta unidad contiene
VOLTAJES PELIGROSOS y sólo deberá abrirla un técnico entrenado y calificado.
Para evitar la posibilidad de ELECTROCHOQUE desconecte la corriente eléctrica
que llega al producto antes de conectar o desconectar los cables LAN.

PELIGRO DE RAYOS
PELIGRO: NO REALICE NINGUN TIPO DE TRABAJO O CONEXION en los

equipos o en LOS CABLES durante TORMENTAS DE RAYOS
ATENCION: EL CABLE DE ALIMENTACION SE USA COMO UN

DISPOSITIVO DE DESCONEXION. PARA DESACTIVAR EL EQUIPO,
desconecte el cable de alimentación.

INSTALACION
ELECTRICO—AUTO-AJUSTE DE TENSION

Este producto se ajustará automáticamente a cualquier tensión entre los valores
máximos y mínimos indicados en la etiqueta.

ELECTRICO—EQUIPO DEL TIPO CLASE 1

ESTE EQUIPO TIENE QUE TENER CONEXION A TIERRA. El cable tiene que
conectarse a un enchufe con tierra debidamente instalado. Un enchufe que no está
correctamente instalado podría ocasionar tensiones peligrosas en las partes
metálicas están expuestas.

ELECTRICO—ADVERTENCIA SOBRE EL CABLE
Use un cable eléctrico con un máximo de 4, 5 metros de largo, con una capacidad
mínima de 6 amperios, 250 V, hecho de cable HAR, con el conector moldeado IEC
320 en un extremo y con un enchufe que está aprobado por el país de uso final en el
otro.

xii

INSTRUCCIONES DE MONTAJE

ATENCION: Estos modelos están diseñados para operar en posición
HORIZONTAL. NO SE DEBEN MONTAR VERTICALMENTE sin el uso de un
chasis de montaje vertical de Allied Telesyn que se ha diseñado para este fin.

ATENCION: CARGA MECANICA - El montaje del equipo en el bastidor debe
realizarse de manera tal que no cause una condición peligrosa debido a la
distribución desigual del peso.

ATENCION: Las aberturas para ventilación no deberán bloquearse y deberán
tener acceso libre al aire ambiental de la sala para su enfriamiento.

ATENCION: NO separe las patas de goma del producto a menos que se esté
usando un chasis de montaje vertical de Allied Telesyn.

TEMPERATURA REQUERIDA PARA LA OPERACIÓN

Este producto está diseñado para una temperatura ambiental máxima de 40 grados
C.

PARA TODOS LOS PAÍSES: Monte el producto de acuerdo con los Códigos
Eléctricos locales y nacionales.

Radiostörning: EN55022 Klass A
VARNING: Denna produkt kan ge upphov till radiostörningar i hemmet, vilket

kan tvinga användaren till att vidtaga erforderliga åtgärder.
Immunitet: EN50082-1
Dessa produkter har säkerhetstestats av UL i enlighet med Standard 1950, av CSA

i enlighet med CSA 950, och av TUV i enlighet med EN60950.

SÄKERHET
TILLKÄNNAGIVANDEN BETRÄFFANDE ELEKTRICITETSRISK:
RISK FÖR ELEKTRISK STÖT

För att undvika ELEKTRISK stöt, ta ej av locket. Det finns inga delar inuti som
behöver underhållas. Denna apparat är under HÖGSPÄNNING och får endast
öppnas av en utbildad kvalificerad tekniker. För att undvika ELEKTRISK STÖT,
koppla ifrån produktens strömanslutning innan LAN-kablarna ansluts eller
kopplas ur.

FARA FÖR BLIXTNEDSLAG
FARA: ARBETA EJ på utrustningen eller kablarna vid ÅSKVÄDER.

VARNING: NÄTKABELN ANVÄNDS SOM STRÖMBRYTARE FÖR ATT

KOPPLA FRÅN STRÖMMEN, dra ur nätkabeln.

INSTALLATION
ELEKTRISKT—AUTOMATISK SPÄNNINGSJUSTERING

Denna produkt justeras automatiskt till alla spänningar inom omfånget som
indikeras på produktens märkning.

ELEKTRISKT—TYP KLASS 1 UTRUSTNING

DENNA UTRUSTNING MÅSTE VARA JORDAD. Nätkabeln måste vara ansluten
till ett ordentligt jordat uttag. Ett felaktigt uttag kan göra att närliggande
metalldelar utsätts för högspänning. Apparaten skall anslutas till jordat uttag, när
den ansluts till ett nätverk.

ELEKTRISKT—ANMÄRKNING BETRÄFFANDE KABELN

Använd en kabel med maximum längd 4,5 meter och minimum 6 amp nominal,
250V, av HAR kabelfabrikat med ett specialutformat IEC 320-kontaktdon i ena
änden och i den andra en plugg som godkänts i landet där produkten används.

xiii

MONTERINGSINSTRUKTIONER
VARNING: Dessa modeller är konstruerade för användning i

HORISONTALLÄGE. VERTIKALMONTERING får EJ UTFÖRAS utan att ett
Allied Telesyn specialkonstruerat vertikalt monteringschassi används.

VARNING: MEKANISK BELASTNING: Utrustningen ska installeras i chassit
på så sätt att fara inte uppstår p g a ojämn belastning.

VARNING: Luftventilerna får ej blockeras och måste ha fri tillgång till omgivande
rumsluft för avsvalning.

VARNING: Ta ej bort gummifötterna från produkten om inte ett Allied Telesyn
vertikalt monteringschassi används.

DRIFTSTEMPERATUR

Denna produkt är konstruerad för rumstemperatur ej överstigande 40 grader
Celsius.

ALLA LÄNDER: Installera produkten i enlighet med lokala och statliga
bestämmelser för elektrisk utrustning.

xiv

Table of Contents

Electrical Safety and Installation Requirements . . . . . . . . . . . . . . . . . .iii

About This Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xix

Document Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xx

Contacting ATI Technical Support. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xx

Telephone and Fax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xx

Bulletin Board Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xx

Internet Mail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xxi

CompuServe Forum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxi

World Wide Web . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xxi

Chapter 1

Product Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

AT-MR420TR Faceplates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Backbone Network Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

10Base2/AUI Backbone Port Switches. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Backbone Enable Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Media Select Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Chapter 2

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Site Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Quick Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

RJ45 Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

AUI Network Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

BNC Network Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

LED Status Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Network Load Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Port Status Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Hub Status Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

xv

Chapter 3

Connectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Four Media Connectors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

AC Power Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

10Base-T Network Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

AUI Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

BNC Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Twisted Pair (RJ45) Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Chapter 4

Topology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Standalone Topology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Cascade Topology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

BNC Terminator Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Backbone Networks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

MDI/MDI-X Switch and Uplink Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

10Base5 Backbone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

10Base2 Backbone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Fiber Optic Backbone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Appendix A

Technical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

The AT-MR420TR/AT-MR820TR Specifications . . . . . . . . . . . . . . . . . . . . . . . 31

Physical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Electrical Rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Connector Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Environmental . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Diagnostic LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Certification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

10Base-T Pin Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Straight-through Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Crossover Wiring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

5 - 4 - 3 Rule. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Appendix B

Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Appendix C

Technical Support Fax Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

xvi

Appendix D

CentreCOM AT-MR420TR/AT-MR820TR Guide Feedback . . . . . . . . . 45

Appendix E

Where To Find Us . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Appendix F

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

xvii

About This Guide

This guide is written for system administrators who are responsible for
configuring, monitoring, and maintaining a Local Area Network (LAN)
of which Allied Telesyn’s AT-MR420TR and AT-MR820TR Micro
Repeaters are components. This guide serves as an installation guide
and reference guide for both products.

The contents of each chapter are described below:

❑ Chapter 1, “Product Description,” provides an overview of the

AT-MR420TR/AT-MR820TR Micro Repeaters including the
backbone network ports and switches.

❑ Chapter 2, “Installation,” describes the site requirements,

quick installation as well as conventional installation
procedures, connections, and LED Status Indicators.

❑ Chapter 3, “Connectivity,” provides instructions associated

with the four media connectors and ports.

❑ Chapter 4, “Topology,” describes uplink and cascading

capabilities in a backbone network topology as well as the MDI/
MDI-X and BNC Termination Switches.

❑ Appendix A, “Technical Specifications,” includes specifications

and basic 10Base-T cabling pin assignments.

❑ Appendix B, “Glossary,” provides a glossary of terms that are

product and industry specific to the AT-MR420TR/
AT-MR820TR.

❑ Appendix C is a “Technical Support Fax Order.”
❑ Appendix D, “Guide Feedback,” offers a means to transmit your

comments and/or suggestions for improving the
documentation.

❑ Appendix E, “Index,” is an index to this guide.
❑ Appendix F, “Where To Find Us,” provides Technical Support

information.

xix

About This Guide

Document Conventions

The following conventions are used in presenting information in this
guide:

Note

A note provides additional information or describes the
possible consequence of a specific action you can perform.

Contacting ATI Technical Support

If you are having problems with your AT-MR420TR/AT-MR820TR, you
can contact ATI’s Technical Support staff by:

❑ Telephone
❑ Bulletin board services
❑ Electronic mail via the Internet
❑ CompuServe forum

When you contact Technical Support, you should have the following
information available:

❑ Serial number of the AT-MR420TR/AT-MR820TR
❑ Power-up test codes, if any
❑ Diagnostic test codes, if any

Telephone and Fax

Refer to Appendix E on page 47 for a complete listing of Technical
Support Telephone and Fax numbers.

Bulletin Board Services

A bulletin board is available. The number is:

206-483-7979

Modem settings for the bulletin board is: 8 bits; no parity; 1 stop bit.

xx

AT-MR420TR and AT-MR820TR Installation Guide

The process is straightforward: Once the BBS is accessed, it requests
that you register either as a new user or as a current user. It then
provides instructions on the various features and functions available.
This is followed by a list and description of all available technical notes
and files that can be downloaded.

Internet Mail

You can send electronic mail via the Internet to:

[e-mail]

CompuServe Forum

ATI has a forum on CompuServe. You can reach us by typing go
allied at the CompuServe prompt (!).

World Wide Web

You can access Allied Telesyn at our Web Site using the following:

http: //www.alliedtelesyn.com

xxi

Chapter 1

Product Description

Overview

Allied Telesyn’s multiport AT-MR420TR/AT-MR820TR Micro
Repeaters represent a compact, inexpensive solution for Local Area

Network (LAN) applications.
AT-MR420TR/AT-MR820TR Micro Repeaters combine 10 Mbps of

10Base-T Ethernet connectivity with the same features and
functionality of larger, more expensive repeaters. At the same time,
they support full-length cable segments with the maximum number of
supported devices allowed within IEEE standards.

While identical in structure, the AT-MR420TR Micro Repeater differs
from the AT-MR820TR Micro Repeater in that the former has 4
Shielded/Unshielded Twisted Pair (STP/UTP) ports whereas the latter
has 8 STP/UTP ports. You can use any one of the STP/UTP ports for
connection to a 10 megabit Ethernet node using Category 3-5 STP/UTP
cabling. The Uplink port provides cascading capabilities to the second
10Base-TX Ethernet hub.

AT-MR420TR Faceplates

Figure 1 and Figure 2, respectively show the front and back panel of
the AT-MR420TR and AT-MR820TR Micro Repeaters. The front panel
consists of eight Network Load LEDs indicating the percentage of
network utilization, and 16 or 8 (depending on version) Link and
Receive status LEDs for each network port. Three additional LEDs
indicate Activity, Collision, and Power for the repeater itself.

1

Product Description

Figure 1: AT-MR420TR and AT-MR820TR Front Panels

Figure 2: AT-MR420TR and AT-MR820TR Rear Panels

On the back panel are four/eight STP/UTP RJ45 network ports,
including Port 4/8, an uplink port, as well as the 10Base5 and 10Base2
backbone network ports, Figure 1 and Figure 2 also show the three-pin
AC power receptacle.

2

AT-MR420TR and AT-MR820TR Installation Guide

Features

The AT-MR420TR/AT-MR820TR Micro Repeaters have incorporated
the latest technologies, including a custom Application Specific
Integrated Circuit (ASIC) and Surface Mount Technology (SMT).
These result in enhanced functionality, increased reliability, improved
performance, and lower cost.

The AT-MR420TR/AT-MR820TR Micro Repeaters have the following
features:

❑ IEEE 802.3 compliant
❑ 10Base-T and Ethernet Version 1.0 and 2.0 compatible
❑ AUI and a BNC ports for connectivity to a network backbone as

well as four/eight twisted pair cable connections

❑ user-selectable AUI or BNC Backbone switch
❑ user-selectable Backbone Network Enable/Disable switch
❑ Network Load LEDs (network utilization)
❑ automatic packet regeneration, error detection and correction
❑ test link capability
❑ auto-partitioning and jabber lock-up protection
❑ status and diagnostic LEDs
❑ STP/UTP uplink port supported for network cascading

Packet Regeneration. Packet regeneration is a high-performance
network feature that includes the regenerating of the packet preamble,
retiming of data packets, and the extension of collision fragments.

Link Integrity. The IEEE 802.3 defined link integrity test function
continually monitors the twisted pair cable to ensure link continuity of
the receive pair between the user node and the repeater.

Auto-partitioning. Also known as segmentation, each segment is
automatically partitioned whenever 32 consecutive collisions are seen
on the segment. One valid packet will reset the segment and reconnect
it.

Jabber Lock-up Protection. Jabber lock-up protects the repeater from
being overrun with data packets by isolating segments with
transmitted packets that exceed the maximum packet length. That is,

3

Product Description

jabber lock-up automatically prevents transmitted data from reaching
the repeater if the transmitted data time exceeds a specified duration
(usually 5 ms).

Backbone Network Port

There are two user-selectable network media options which can be
used to connect to a backbone network: 10Base2 and 10Base5.

These network ports are located on the back panel. See Figure 3.

Figure 3: Network Media Options

These media alternatives are:

❑ 10Base2 (Bayonet Nut Couple [BNC])

— 10Base2 requires a thin coaxial cable, RG58U, which is a 10

MHz baseband cable that uses BNC-series connectors. The
cable must be terminated at both ends with 50 Ω
terminators and grounded at one end. Maximum segment
length is 185 meters (606 ft.). Internal termination is
provided via the BNC Terminator Switch. See Chapter 4
“BNC Terminator Switch” for details concerning this
switch.

4

AT-MR420TR and AT-MR820TR Installation Guide

❑ 10Base5 (Attachment Unit Interface [AUI])

— Located to the right of the BNC port, the 10Base5 network

port connects the repeater to the network using standard (
thick) Ethernet cable and AUI-series connectors.
Alternatively, you can fit an Allied Telesyn 802.3
transceiver into this port for alternative media connections,
for example fiber optics.

Although both network ports are always available, only one can be
active at a time and, since there is no default port, you determine the
active port by using the Backbone Enable and Media Select switches —
both of which will be discussed next.

10Base2/AUI Backbone Port Switches

There are two user-selectable switches: a Backbone Enable and Media
Select. See Figure 4.

Figure 4: Backbone Switches

5

Product Description

Backbone Enable Switch

This dual-position switch allows you to activate the backbone network
AUI and BNC ports.

When this switch is ON (default position), it is depressed below the
surface of the chassis. The ON position (enabled) indicates that both
10Base2 and AUI ports have a backbone network capability.

Deactivating the switch to OFF (disabled) means that the switch is
flush with the surface of the chassis. As a result, the ports are not
capable of connecting to a backbone network.

Media Select Switch

The Media Select switch is only active after the Backbone Enable
switch is activated. It functions as the name implies — you have the
ability to determine the medium of connectivity to the network
backbone: either the 10Base2 (BNC) port or the 10Base5 (AUI) port
(but not both).

The default position is AUI (the switch is flush with the surface of the
chassis).

The AUI port also allows you to attach an optional, inexpensive
external micro transceiver for additional LAN connectivity using
thinnet, twisted pair or fiber optic cable.

When the switch is pressed below the surface of the chassis, the
10Base2 port is selected. Notice that the 10Base2 backbone port also
includes a user-selectable 50 Ω terminator switch. The use of the
terminator switch is discussed in Chapter 4.

6

Chapter 2

Installation

Site Requirements

Ventilation

AT-MR420TR/AT-MR820TR Micro Repeaters have grilled openings
on both sides for ventilation. Although they do not require an internal
fan to aid in cooling, adequate ventilation is required. Ensure that the
ventilation openings located on the sides of the chassis are never
blocked.

Note

Maximum ambient operating temperature is 104o F (40o C).

Power

Be sure that the voltage and frequency is either 100-120 or 200-240
VAC and 60 or 50 Hz respectively. Since there is no external power
switch, power is applied when the power cord is connected.

Note

For countries other than the United States and Canada: use a
power cord that is rated at 6 amp, 250 VAC. Also note that this
cord cannot exceed 4.6 meters (15 ft.) in length and must be
made of HAR cordage with IEC fittings that are approved by
the country of end use.

7

Installation

Quick Installation

1. Carefully remove the AT-MR420TR/AT-MR820TR Micro
Repeaters from their packaging materials. Keep the packing

materials until you have successfully installed the product.

2. Place them in a location with adequate ventilation and power
receptacles.

3. Apply power by plugging in the AC cord and ensure that the
POWER LED on the front panel is illuminated.

4. If you are connecting to a backbone network, prepare either the
AUI or BNC cable for attachment.

5. Attach your 10Base-T STP/UTP cables, with RJ45 connectors to
the 10Base-T ports. If the UPLINK port is not used for cascading,
you may connect a standard 10Base-T cable to port 4/8.

6. If the AT-MR420TR/AT-MR820TR Micro Repeaters are to be
connected to an external transceiver, attach a transceiver to the
15-pin AUI connector on the back panel. Ensure that the external
transceiver has its Signal Quality Error (SQE)/Heartbeat Test
function disabled. When power is applied to the AT-MR420TR/
AT-MR820TR Micro Repeaters, the external transceiver should
also have power.

Note

Because of the default switch positions, you do not have to
changes any switches.

8

AT-MR420TR and AT-MR820TR Installation Guide

Connections

The AT-MR420TR/AT-MR820TR Micro Repeaters have the following
connectors:

❑ RJ45
❑ AUI
❑ BNC

RJ45 Ports

Attach an RJ45 10Base-T STP/UTP cable to port 1. The respective
segment LINK OK LED located on the front panel should light when
the 10Base-T network adapter card in the device on the opposite end of
the STP/UTP segment is operational. If not, check that the card on the
opposite end of the STP segment is operational, then ensure that the
proper cable is being used.

Attach a second 10Base-T STP RJ45 connector to 10Base-T network
port 2. The port 2 LINK OK LED on the front panel should light,
provided the 10Base-T device on the opposite end of the STP/UTP cable
is operational.

AUI Network Port

Each AT-MR420TR/AT-MR820TR Micro Repeater has one AUI port to
accommodate a 10Base5 (standard or thick Ethernet cable) connection
to the network backbone using an AUI or convert the media type, for
example fiber optics.

BNC Network Port

Each AT-MR420TR/AT-MR820TR Micro Repeater has one BNC port
to accommodate a 10Base2 (cheapernet or thin Ethernet cable)
connection to the network backbone.

9

Installation

LED Status Indicators

The front panel indicators are grouped into the following categories:

❑ Network Load
❑ Port Status
❑ Hub Status

Network Load Indicators

Eight Network Load LEDs indicating the percentage of network
utilization, are located on the front panel. Figure 5 shows these LEDs.

Figure 5: Network Load Indicators

Port Status Indicators

Two Port Status indicators are associated with each 10Base-T (RJ45)
network port. Located on the front panel of the repeater, these LEDs
indicate whether the port is linked, receiving data, or both. See
Figure 6.

10

AT-MR420TR and AT-MR820TR Installation Guide

Note

A data packet is too fast for the human eye to distinguish on
an LED, therefore the LEDs will not reflect real-time activity.
The repeater artificially stretches the LED on time for easier
observation.

Figure 6: Port Indicators

Each RJ45 repeater port has two LEDs — LINK OK and Receive:

❑ LINK OK

— No light—Indicates typically a physical connection problem.

The device at the other end of the cable may be powered off,
the cable may be loose or disconnected, or the cable has been
wired incorrectly. Check the crossover cable.

— Green (Steady)—Indicates a valid link exists.

❑ Receive

— Amber (Flashing)—Link is OK, port is not partitioned and

there is activity on the port. Brief flashes indicate low traffic
levels.

In short, port status LEDs show the functionality of the port. If the
LINK OK status light is green and the Receive status is flashing
amber, a signal is being received and the segment attached to the port
is functional.

11

Installation

If there is no link light, there is no signal continuity.

Check that the attached Data Terminal Equipment (DTE) is ON and
that the proper cable is being used.

If this check does not identify the problem, it may indicate that a
repeater or the device connected to the port is faulty. Move the cable to
the adjacent ports to further isolate the problem to the repeater or to
the attached device. It may be necessary to change cables to isolate the
fault to a particular cable.

Hub Status Indicators

Three Hub status LEDs at the far right of the front panel indicate the
overall status of the repeater. Figure 7 shows the location of these
indicators.

Figure 7: Hub Status LEDs

12

AT-MR420TR and AT-MR820TR Installation Guide

Table 1: Hub Status LEDs

LED Color Description

Power green lights when AC power is applied
Collision

1

amber flashes indicating an SQE or frame collisions on a

segment. This may be caused by an overloaded
segment, faulty cable, or loose connection.

Activity green indicates that the repeater is functional and is

transmitting packets

1

Occasional collisions are normal in Ethernet networks. A constantly illuminated Collision

LED may indicate that there is a prt with excessive traffic problems. If the Collision LED is
flashing steadily, and you are using an external transceiver on the AUI backbone port, make
certain that the SQE/Heartbeat Test function is disabled. Repeaters do not function properly
when the SQE/Heartbeat Test is active.

System Check

1. Check the LINK OK LED on the front panel for the first 10Base-T
port that is connected. A steady green LED indicates continuity. A
valid network connection must be made from the connected port to
a host or workstation on another port.

2. After a successful connection, disconnect the active 10Base-T
connector and connect it to the next successive port. Continue this
process until all 10Base-T ports have been validated with good
network connections.

3. Establish a connection from a device connected to port 1 to a device
connected to port 2.

4. Once the connection between devices attached to ports 1 and 2 has
been successfully established, remove the RJ45 connector from port
2 and connect it to each of the subsequent repeater’s 10Base-T
ports, 3 through 4/8, to verify their functions.

5. If all ports test successfully, install the rest of the 10Base-T RJ45
connections and ensure that the LINK LED for each port is
illuminated. Remember, the 10Base-T device on the opposite end of
the STP/UTP cable must be operational.

13

Installation

Note

The LINK LED validates the receive pair only. The opposite
end of the STP segment is responsible for validating the
transmit pair.

14

Chapter 3

Connectivity

Four Media Connectors

This repeater has four types of ports and media connectors:

❑ AC input power connector
❑ 10Base5 (AUI) network backbone port
❑ 10Base2 (BNC) network backbone port
❑ Four/Eight STP/UTP 10Base-T (RJ45) ports

These four types of connecting media are described in the following
sections.

AC Power Connector

While it is common to use dedicated power circuits or power
conditioners to supply power to network devices, the source must be
able to provide AC power at 100-120 VAC, 0.5A, and/or 200-240VAC,

0.25A, and 60/50 Hz (for North American models). This aids in isolating

the network equipment from electrical power “noise.”
The AC power connector is located on the back panel and provides

connectivity for an internal power supply. It accepts 100-120 or
200-240 VAC from the rear IEC power entry port. The three-pin power
receptacle, shown in Figure 8, requires a three-pin male connector.

15

Connectivity

Figure 8: Power Connector

16

AT-MR420TR and AT-MR820TR Installation Guide

10Base-T Network Specifications

Table 2 provides an overview of the IEEE 802.3 specifications for
10Base-T network configurations using thick, thin, and twisted-pair
wiring.

Table 2: IEEE 802.3 Network Specifications

10Base-T 10Base2 10Base5

Media Twisted Pair

Cable

Thin Coaxial

Cable

Thick Coaxial Cable

Topology Star, Tree Bus Bus

External Devices Network

Adapter Card

Network

Adapter Card

Network Adapter

Card and External

Transceiver

Maximum

Segment Length

Maximum

100 meters

(328 ft.)

185 meters

(605 ft.)

_ 30 100

457 meters

(1,500 ft.)

Devices per

Segment

Maximum

_ 1,024 1,024

Devices per

Network

AUI Port

The AUI port is a 15-pin D-sub female connector, located on the back
panel. This AUI backbone port connects the repeater to the network
using a standard AUI drop cable. See Figure 9. Alternatively, you can
fit any of a variety of Allied Telesyn’s 802.3 transceivers into this port
should you select a different medium such as fiber optics.

17

Connectivity

Figure 9: AUI Network Port

10Base5 (Thick) Ethernet Cable. When configuring 10Base5 coax

segments, IEEE 802.3 specifications allow a maximum of 100 MAU
attachments, spaced at multiples of 2.5 meters (8.2 ft.) measured
accurately from the cable end (50 Ω terminator included). The 10Base5
cable segment should not exceed 500 meters (1,640 ft.). Worst-case
“end-to-end” propagation delay of a 10Base5 coax segment is 2165 ns.
Propagation delay of 10Base5 Ethernet coax is calculated at 4.33 ns/
meter. Both ends of the segment must be terminated with a 50 Ω
termination with a power rating of 0.5 watts or greater. Earth
grounding of the segment shield is allowed at only one point on the
cable.

AUI Drop Cables. AUI or drop cables should not exceed 50 meters
(164 ft.) each. Attachments may be made only to the cable ends at the
15-pin D-shell connector. AUI cables may have a maximum 257 ns
propagation delay, as used for computing the worst-case propagation
delay of a cable system. AUI cable propagation delay is approximately

18

AT-MR420TR and AT-MR820TR Installation Guide

5.13 ns/meter. This cable internally consists of four shielded twisted

pair wires with an overall shield and drain wire; a 15-pin D-shell male
connector at one end and a 15-pin D-shell female connector at the other
end. Cable impedance is nominally 78 Ω. The AUI cable typically
connects a transceiver attached to a coaxial segment to a DTE
(workstation).

BNC Port

10Base2 requires an RG58U, thin coaxial cable. This cable is a 10
Mbits/sec baseband with 50 Ω impedance. See Figure 10. Connected
with BNC-series connectors, the maximum segment length is 185
meters (606 ft.).

10Base2 (Thin) Ethernet. When configuring thin coax segments, IEEE

802.3 specifications allow 30 or fewer MAUs per cable segment spaced

at no less than 0.5 meter (1.64 ft.). The 10Base2 cable length cannot
exceed 185 meters (606 ft.) per 10Base2 cable segment. The worst case
propagation delay for a 185 meters (606 ft.) thin Ethernet segment is

950.9 ns. The propagation delay for 10Base2 Ethernet cable is 5.14 ns/

meter. Both ends of the segment must be terminated with a 50Ω
termination with a power rating of 0.5 watts or greater. The
AT-MR420TR and AT-MR820TR repeaters provide internal 50Ω
terminator with a slide switch. Earth grounding of the segment shield
is required at only one point on the cable.

Figure 10: BNC-T Connector

19

Connectivity

Twisted Pair (RJ45) Connector

Figure 11 shows a twisted pair cable with RJ45 connectors. For a
10Base-T link between a repeater and a Medium Attachment Unit
(MAU) or Network Interface Controller (NIC), the cable is wired
straight through.

Figure 11: RJ45 Connector

10Base-T STP cables can be up to 100 meters (328 ft.) in length. The
cable should be 22 to 26 AWG TP wire with 100Ω impedance and rated
at Category 3, 4, or 5. The AT-MR420TR/AT-MR820TR Micro
Repeaters use RJ45 modular connectors for 10Base-T connections.

10Base-T Cable. The AT-MR420TR/AT-MR820TR Micro Repeaters
support full-length, fully repeated transmission and maximum node
attachments which, for the STP/UTP link, enables transmissions to
100 meters (328 ft.).

A serious problem exists concerning identification of modular cable.
There are various grades of voice-quality and data-quality cables
available. These can appear to be similar, but their high-speed data
transmission characteristics are significantly different. Some suppliers
have sold purportedly data-quality cables manufactured with voice­quality cabling.

If any voice-quality cabling is used in a 10Base-T network system, data
movement is slow, collision-prone or non-existent. To confuse the issue,
the Link indicator on the interface usually indicates a valid link.

20

AT-MR420TR and AT-MR820TR Installation Guide

10Base-T connections require Category 3, 4, or 5. In most cases, if a
cable type is flat, it is typically untwisted and can cause problems.
Generally, cable that is more or less round in section, gives better
results.

Hub to MAU Wiring. The most typical TP cable for the AT-MR420TR/
AT-MR820TR Micro Repeaters is TP Hub to TP transceiver Data

Terminal Equipment (DTE).
To configure your own cables, see Appendix A, “Technical

Specifications.”

21

Chapter 4

Topology

Standalone Topology

Figure 12 shows a standalone topology. Four workstations are
connected directly to the repeater through the repeater’s RJ45 ports.

100 Meters

TP cable

wired 

Pin to Pin

10BaseT

Tranciever

Figure 12: AT-MR420TR Standalone Topology

Cascade Topology

A shared Ethernet network can be expanded by interconnecting
repeaters (cascading) through the UTP ports. Figure 13 shows a
cascaded topology using four repeaters which is the maximum number
of micro repeaters and nodes in a single segment: four micro repeaters
with ten (AT-MR420TR)/twenty-six (AT-MR820TR) ports. Its design
complies with the four-repeater rule. Additional UTP ports are
available if the AUI port is used for cascading.

23

Topology

Figure 13: AT-MR820TR Four Cascaded Repeaters

The Four-Repeater Rule. The IEEE 802.3 standard provides general

rules for 10Base-T cable length and network connections on single
segments of cable or on point-to-point links with media attenuation
and signal propagation delays. The basic rule applies for all networks.
The maximum number of repeaters in the data path between any two
nodes cannot exceed four.

BNC Terminator Switch

The BNC Terminator switch is located on the rear panel to the left of
the BNC connector. Use this switch to enable or disable internal
termination at this end of the 10Base2 segment.

If you are installing BNC-T connectors in the center of a segment, the
termination switch must be disabled (OFF). The general rule is to
terminate at each end of the cable segment. If the cable is connected
directly into the port without a T-connector (end of segment), turn ON

24

AT-MR420TR and AT-MR820TR Installation Guide

the termination switch. Figure 14 shows the location of the two­position 50 Ω Terminator switch. The switch is either ON (the default)
or OFF.

Figure 14: Terminator Switch

OFF (disabled) — When installing a hub at an intermediate point of a
thinnet cable, a BNC-T connector must be used to connect the cable to
the backbone port and the terminator switch must be disabled. See
Figure 14.

ON (enabled) — When installing a hub at the end of the cable, if you
need to remove the BNC-T connector and the terminator, the backbone
port must be connected directly to the thinnet cable. The terminator
switch must be enabled. This provides the 50 ohm termination that is
required.

❑ Use the OFF position to disable termination if you are

installing a link segment with a BNC-T connector on this port.

❑ Use the ON position to enable termination if you are installing

a link segment without a BNC-T connector at this port, and if
the unit is at the end of the cable.

25

Topology

Backbone Networks

The most straightforward topology is a backbone network. Figure 15
show a backbone network topology with the AUI port attaching to a
coaxial Ethernet cable.

Coaxial Backbone

100 Meters

maximum

Category 3-5

STP/UTP cable

wired Pin to Pin

AUI cable

Ethernet

Transceiver

Figure 15: AT-MR820TR Backbone Topology

In a backbone network topology, each workgroup has its own local
network and the backbone is used to link the various workgroups
through the bridges. The advantages of a backbone network topology
are twofold:

❑ When the backbone network is operating correctly, any

problem within a sub-network does not affect other sub­networks.

❑ Since faults are isolated to a single sub-network, they are

easier to locate.

MDI/MDI-X Switch and Uplink Port

While any RJ45 port can be used to cascade repeaters, port 4/8 has
been specifically designed with an uplink (cascading) capability, by
providing a Media Dependent Interface (MDI/MDI-X) switch.

Cascading through port 4/8 means if a single, standalone
AT-MR420TR/AT-MR820TR Micro Repeater can support 4/8 ports,
when a second AT-MR420TR/AT-MR820TR Micro Repeater is
uplinked (cascaded) using the port 4/8 of the first unit to any port of a

26

AT-MR420TR and AT-MR820TR Installation Guide

second unit. A maximum of four repeaters (the four repeater rule) can
be interconnected. The network effectively consists of 6 nodes for the
AT-MR420TR and 14 nodes for the AT-MR820TR. The Uplink port is
located on the back panel, as shown in Figure 16.

Figure 16: Uplink Port for MR420TR/820TR

Port 4/8 has the ability to become a dedicated uplink port. To facilitate
this process, it uses a Media Dependent Interface (MDI/MDI-X) switch.

An MDI/MDI-X switch is a crossover/straight-through cable selection
slide switch. As shown in Figure 16, the MDI/MDI-X switch converts
the 10Base-T (RJ45) Port 4/ 8, to an uplinkable port that allows one
repeater to connect to another repeater without requiring special
crossover cables.

The default setting for the RJ45 pinout switch is MDI-X (standard
RJ45 port), which means the slide switch is to the right.

❑ In the default MDI-X configuration you can connect the

10Base-T port to a workstation or to any other DTE (that is,
node).

27

Topology

❑ In the MDI configuration — the slide switch is to the left — you

can connect the 10Base-T port to another 10Base-T internal
crossover port, that is, a repeater using straight-through
twisted pair cable to form an interrepeater link. See Figure 16.

If you use this port to connect repeaters to each other, the RJ45 pinout
switch must be set to MDI. The MDI position is a repeater pinout which
automatically swaps the TX and RX pinouts so that they do not conflict
with the TX and RX ports at the other end of a straight-through cable.

If you connect a straight-through cable to another repeater or DTE and
the Link LEDs on the respective units are not on, change the position
of the MDI/MDI-X switch to obtain continuity as indicated by active
Link lights. The repeater will not be damaged if the MDI/MDI-X switch
is in the wrong position.

In general, if you install an RJ45 port cable, and the Link LED does not
light, then simply change the position of the MDI/MDI-X slide switch
and see if the Link LED lights.

10Base5 Backbone

Figure 17 illustrates a single multiport 10Base-T AT-MR820TR Micro
Repeater connecting to a thick Ethernet backbone using a transceiver.

100 Meters

maximum

Category 3-5
STP/UTP cable
wired Pin to Pin

28

Coaxial Backbone

AUI cable

Figure 17: 10Base5 Backbone Topology

Ethernet

Transceiver

AT-MR420TR and AT-MR820TR Installation Guide

10Base2 Backbone

A maximum of 30 AT-MR420TR/AT-MR820TR Micro Repeaters can
be connected in a network using 10Base2 (thin Ethernet). When you
use the BNC port, you avoid using transceivers to complete the linkage.
See Figure 18.

Figure 18: AT-MR820TR on a Backbone Using the BNC Network Port

29

Topology

Fiber Optic Backbone

By attaching a fiber optic transceiver, the AUI port can connect your
network to a fiber optic (10Base-FL/FOIRL) cable backbone.

100 Meters

maximum

Category 3-5

UTP cable

wired 

Pin to Pin

Fiber Optic
Transceiver

Fiber Optic cable

Figure 19: AT-MR820TR on a Fiber Optic Backbone

The advantages of fiber optic cable are as follows:

❑ immune to electromagnetic interference
❑ spans longer distances without attenuation
❑ eliminates grounding problems
❑ secure from unauthorized taps

10Base-FOIRL. The IEEE FOIRL (fiber-optic inter-repeater link)
standard limit of a fiber segment is 1 km. The fiber optic cable that
connects two repeaters is limited to 1 km.

10Base-FL. The more recent IEEE 10Base-FL standard extends a fiber segment length to 2 km. This applies only to topologies in which one 10Base-FL node connects to another 10Base-FL node.

30

Appendix A

Technical Specifications

The AT-MR420TR/AT-MR820TR Specifications

Physical

Height 37.6 mm (1.55 in.)
Width 332 mm (13 in.)
Depth 112 mm (4.4 in.)
Installation options Tabletop or rack-mount

Electrical Rating

Input voltage 100-120 or 200-240 VAC
Frequency 50 or 60 Hz
Amperage 0.5/0.25 Amp

Connector Ports

4/8 RJ45 Ethernet ports (MDI-X)
1 AUI D-type, 15-pin female port
1 BNC female port

Environmental

Operating temperature 0˚ to +40˚ C (32˚ to 104˚ F)
Relative humidity 0% to 95%, non-condensing

31

Technical Specifications

Diagnostic LEDs

Individual port link status (4/8)
Individual port receive activity (4/8)
Hub status (3), specifying:

❑ Both Transmit and Receive activity
❑ Collision
❑ Power

Certification

Safety UL 1950, CSA 22.2 No. 950 (Canadian

Standards Association), TUV EN60950

Emission FCC Part 15 Class A, VCCI Class 1,

CDOC Class A, EN55022 (CISPR 22)
Class A

10Base-T Pin Assignments

An Ethernet twisted-pair link segment requires two pairs of wires.
Each wire pair is identified by solid and striped colored wires. For
example, one wire in the pair might be red and the other wire, red with
white stripes.

32

AT-MR420TR and AT-MR820TR Installation Guide

Connectors

Notice how the pins are numbered in Figure 20. Be sure to hold the
connectors in the same orientation when connecting the wires to the
pins.

8

1

8

1

Figure 20:

Connector Pin Numbers

Each twisted-pair link segment must have a male connector attached
to both ends. According to the 10Base-T specification, pins 1 and 2 on
the connector are used for transmitting data; pins 3 and 6 are used for
receiving data, as shown in Table 3. The TX and the RX in Table 3
represent Transmitted Data and Ready Data, respectively.

Table 3: Pin Assignments

Pin Assignment *

1 TX+
2 TX­3 RX+
6 RX-

*The “+” and “-” signs are used to represent the polarity of the two wires that make up each

wire pair.

33

Technical Specifications

Straight-through Wiring

If the twisted-pair link segment is to join two ports on a switch, and
only one of the ports has an internal crossover, the two pairs of wires
must be straight-through, as shown in Table 4.

Table 4: Straight-through RJ45 Pin Assignments

Hub Device

1 (TX+) 1 (TX+)

2 (TX-) 2 (TX-) 3 (RX+) 3 (RX+) 6 (RX-) 6 (RX-)

Crossover Wiring

Two AT-MR420TR/AT-MR820TR Micro Repeaters can communicate
only if the transmitter on one unit is connected to the receiver on the
other unit. This reversal, or crossover function, can be implemented
either in the wiring or in the device itself using the MDI/MDI-X switch.
When connecting AT-MR420TR/AT-MR820TR Micro Repeaters, a
crossover must be used in the wiring when using any port other than
4/8. See Table 5 for crossover pin assignments.

Table 5: Crossover RJ45 Pin Assignments

AT-MR420TR/MR820TR AT-MR420TR/MR820TR

1 (TX+) 3 (RX+)

2 (TX-) 6 (RX-)

3 (RX+) 1 (TX+)

6 (RX-) 2 (TX-)

34

AT-MR420TR and AT-MR820TR Installation Guide

5 - 4 - 3 Rule

In addition to the requirements outlined in Chapter 3, Table 2, follow
the “5-4-3 rule” to ensure that your configuration does not exceed the
maximum 10Base-T data transmission path (the longest path through
any given network).

The 5-4-3 rule describes the maximum path between any two devices
or nodes (PCs or other stations) on the network. There can be:

❑ Up to five segments in series
❑ Up to four repeaters or multiport hubs
❑ Up to three populated segments (that is, segments attached to

two or more PCs)*

* The remaining two segments are unpopulated; these are known as
inter-repeater links or IRLs. This distinction between populated and
unpopulated segments is significant for coax networks only.

Note

This rule is completely consistent with the IEEE 802.3
specification, and is meant only to summarize the
configuration specification.

35

Appendix B

Glossary

10Base2—Also called thin Ethernet, thinnet or CheaperNet, a 10 MHz
baseband specification. Cable impedance is 50 Ω and maximum coaxial
segment length is 185 meters (607 ft.).

10Base5—Also called thick Ethernet, a 10 MHz baseband specification. Cable
impedance is 50 Ω and maximum coaxial segment is 500 meters (1,640 ft.). The
cable is commonly referred to as yellow cable. Thick Ethernet cable is typically
used as a trunk or backbone path of the network.

10Base-T—IEEE 802.3 STP/UTP Ethernet. Low-cost Level 3 or better STP/
UTP wiring affords 100 meters (328 ft.) of point-to-point link segments. STP/
UTP uses RJ45 connectors and sometimes 50-pin Telco connectors to a patch
panel and runs at 10 MHz.

ATTACHMENT UNIT INTERFACE (AUI)—Connection between a MAU
(transceiver) and a DTE (typically a workstation). Includes a 15-pin D-sub
connector and sometimes a 15-conductor twisted pair cable. Maximum length
is 50 meters (164 ft.).

BASEBAND COAXIAL SYSTEM—A system whereby information is directly
encoded and impressed on the coaxial transmission medium. At any point on
the medium, only one information signal at a time can be present without
disruption.

BAYONET NUT COUPLE (BNC) CONNECTOR—A 10Base2 thin coax
connector with push-on BNC locking lug that quickly locks into place with a
half twist.

BIT RATE (BR)—The rate of data throughput on the medium in bits per
second. Ethernet specifies 10 million bits per second.

BIT TIME—The duration of one bit symbol (1/BR). Ethernet specifies a bit
time of 100 ns.

CARRIER SENSE—In a LAN, an ongoing activity of a data station to detect
whether another station is transmitting.

CARRIER SENSE MULTIPLE ACCESS with COLLISION DETECT
(CSMA/CD)—This is the access method employed by IEEE 802.3 LAN

transceivers, by which multiple stations compete for use of the transmission

37

Glossary

medium (coax cable) for data packet transmission. It provides for a level of error
detection should that transmission be corrupted or impeded by contention for
the transmission medium.

COAX SEGMENT—A segment of Ethernet cable that contains MAUs.
COAXIAL CABLE—A two-conductor (center conductor, shield system),

concentric, constant impedance transmission line used as the trunk medium in
the baseband system.

COAXIAL CABLE SEGMENT—A length of coaxial cable sections and coaxial
connectors, terminated at each end in its characteristic impedance.

COLLISION—An unwanted condition that results from concurrent
transmissions on the physical medium.

COMPATIBILITY INTERFACE—The MDI coaxial cable interface and the
AUI branch cable interface, the two points at which hardware compatibility is
defined to allow connection of independently designed and manufactured
components to the baseband transmission system.

CROSSOVER—Wiring used when connecting a 10Base-T MAU to another
10Base-T MAU or a 10Base-T hub to another 10Base-T hub. For example, one
10Base-T MAU has the TD (Transmitted Data) pair on the same pins as
another 10Base-T MAU. If pins were wired straight, there would be two
transmitters on one pair and no receiver. As a solution, the crossover cable
crosses the TD pair with the RD (Ready Data) pair, to connect the TD pins on
one end to the RD pins at the other end.

D-SUB CONNECTOR—The AUI cable uses 15-pin D-sub connectors. “D”
refers to the shape of the connector shell. Also called miniature D, DB15, or DIX
connectors.

DATA COMMUNICATION EQUIPMENT (DCE)—In RS-232 specification,
a module, such as a modem, for connecting a DTE to other equipment. A
repeater connected to a terminal or workstation for Omega management use is
wired as a DCE.

DATA TERMINAL EQUIPMENT (DTE) —In RS-232 specification, a module
typically at the end of a segment (i.e., uninterrupted length of Ethernet cable).
The DTE could be an Ethernet workstation, repeater or bridge.

DIX CONNECTOR—See D-Sub Connector
HEARTBEAT—See Signal Quality Error
HOUSE WIRING—House wiring is the existing wiring inside a building. This

wiring generally originates from one or more wiring closets, such as a telephone
room. Some older buildings may have wiring unsuitable for 10 megabit data
rates. In these circumstances, it is recommended that the wiring be tested with
a 10Base-T signal/wire tester.

38

AT-MR420TR and AT-MR820TR Installation Guide

HUB/REPEATER—A hub is a central signal distributor. It is used in a wiring
topology consisting of several point-to-point segments originating from a
central point. The term hub is often used interchangeably with the term
repeater. Multiport 10Base-T, 10Base2 and fiber optic (10Base-FL, FOIRL)
repeaters are considered hubs. See Repeater.

HUB-to-HUB WIRING—See MAU-to-MAU Wiring
HUB-to-MAU WIRING—STP/UTP cables for 10Base-T hub-to-MAU or NIC

cards are wired straight-through. An RJ45 receptacle at the hub would wire
pin-to-pin to the RJ45 receptacle at the MAU.

IMPEDANCE—An electrical characteristic of a circuit dealing with the
combination of the AC and DC resistance and the appearance of that resistance
to attached circuits.

JABBER LOCK-UP—The MAU’s ability to automatically inhibit the transmit
data from reaching the medium if the transmit data time exceeds a specified
duration. This duration is in the range of 20 ms to 150 ms. Jabber lock-up
protects the medium from being overrun with data packets from a possibly
defective device.

JAM—This is a term used to describe the collision reinforcement signal output
by the repeater to all ports. The jam signal consists of 96 bits of alternating 1s
and 0s. The purpose is to extend a collision sufficiently so that all devices cease
transmitting.

JITTER—The shift of the data bit in respect to a standard clock cycle. Jitter is
undesirable and must be minimized.

LINK SEGMENT—The link segment of coaxial cable is a segment that has no
MAU devices, but links together two LAN devices such as repeaters.

LINK TEST—In 10Base-T Ethernet there is a link test function that validates
the STP/UTP link. This consists of a pulse transmitted from point A on one pair
that is validated at point B. Point B also transmits a pulse on the second pair
to be validated by point A. These pulses occur during media idle states (in
between packets).

MAU—See Medium Attachment Unit
MAU-to-MAU, HUB-to-HUB WIRING—10Base-T MAU-to-MAU or hub-to-

hub wiring generally requires a cross-over cable located somewhere along the
STP/UTP cable run. This may commonly occur at the punch-down block or
between the RJ45 wall receptacle and the workstation.

MAU/TRANSCEIVER—An Ethernet transceiver is a MAU. A 10Base-T MAU
interfaces the STP/UTP media to an AUI port on a workstation, repeater,
bridge or other Ethernet device.

MDI/MDI-X—See Medium Dependent Interface

39

Glossary

MEDIUM ATTACHMENT UNIT (MAU) —In a LAN, a device used in a data
station to couple the DTE to the transmission medium.

MEDIUM DEPENDENT INTERFACE (MDI)—The mechanical and
electrical interface between a hub and a transceiver (MAU). MDI-X is another
version of the interface that enables hubs to connect using different pin-outs,
thereby avoiding conflicts that occur when receiving and transmitting packets
use the same pin-out.

N-SERIES—A barrel shaped, threaded connector used on 10Base5 (thick
Ethernet) coaxial cable.

PATCH PANEL—A 10Base-T patch panel may be used between a punch­down block and STP/UTP workstation. The patch panel generally has a female
RJ45 connector on the front for each workstation and a Telco (RJ21) connector
on the back, which is wired to a punch-down block. This provides a convenient
way for the installer or network manager to connect the hub 10Base-T ports
into the desired building locations.

POLARITY CORRECTION—Many 10Base-T STP/UTP ports have a polarity
correction function. If the STP/UTP wiring has RD- and RD+ inadvertently
crossed, the polarity correction function will sample the signal and electrically
swap the wires. If the TD- and TD+ wires are crossed, the correction would
occur at the MAU on the other end of the STP/UTP link. This occurs within a
single pair and should not be confused with the crossover cable.

PROPAGATION DELAY—The time it takes a signal to travel from the input
of a system component to the output. Usually measured in nanoseconds. IEEE

802.3 has specific propagation delay maxima for computing propagation
budgets when designing a LAN. Cable length plays a major role in propagation
delay; for example, a 50-meter (164-foot) AUI cable has a maximum allowable
propagation delay of 257 ns. The propagation delay of cable depends on the
length and velocity factor of the cable type. There are also propagation delays
associated with electronics attached to the system.

PUNCH-DOWN BLOCK—The punch-down block is the wiring panel where
the house wiring from the building’s offices terminates. This is where many
10Base-T hubs would be located. Wiring installers use a special punch-down
tool to insert the STP/UTP wire for data and voice applications.

REPEATER—A device used to extend the length, topology, or
interconnectivity of the physical medium beyond that imposed by a single
segment, up to the maximum allowable end-to-end trunk transmission line
length. Repeaters perform the basic actions of restoring signal amplitude,
waveform and timing applied to normal data and collision signals.

RJ45—This connector is a 10Base-T standard for connecting STP/UTP cabling.
SIGNAL QUALITY ERROR (SQE)—Also referred to as Collision or Collision

Presence. This occurs when two devices attempt to transmit at the same time,
which is an illegal condition. All ATI transceivers test for SQE.

40

AT-MR420TR and AT-MR820TR Installation Guide

SQE TEST—Commonly referred to as Heartbeat, is a special 802.3 signal sent
by the MAU to the DTE to test the collision detection function. Some DTE want
SQE and others do not. Repeaters do not want the SQE Test.

STRAIGHT-THROUGH—A type of wiring connection where the pins of one
connector connect to the same pins of another connector. For example, pin 1 of
one connector connects to pin 1 of another connector.

THICK ETHERNET—See 10Base5
THIN ETHERNET—See 10Base2
TRUNK CABLE—The coaxial cable used to distribute signals over long

distances throughout a cable system.
UNSHIELDED TWISTED PAIR (UTP)—A cable used in 10Base-T wiring

that consists of at least two twisted pairs of 22 to 26 AWG wire. The pairs
should have at least 3 twists per foot and have an impedance of 100 Ω. Level 3,
Level 4 and Level 5 UTP cables fit these criteria.

41

Appendix C

Technical Support Fax Order

Name__________________________________________________________________
Company _______________________________________________________________
Address ________________________________________________________________
City ________________________State/Province _______________________________
Zip/Postal Code ___________________ Country _______________________________
Phone _______________________________Fax _______________________________

Incident Summary

Model number of Allied Telesyn product I am using _____________________________
Network software products I am using________________________________________

______________________________________________________________________

Brief summary of problem _________________________________________________

______________________________________________________________________

Conditions (List the steps that led up to the problem.) ___________________________

______________________________________________________________________
______________________________________________________________________
______________________________________________________________________

Detailed description (Use separate sheet, if necessary)

______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________

When completed, fax this sheet to the appropriate ATI office. Fax numbers can be found
on page 47.

43

Appendix D

CentreCOM A T-MR420TR/A T -MR820TR Guide Feedback

Please tell us what additional information you would like to see discussed in the guide. If there
are topics you would like information on that were not covered in the guide, please photocopy
this page, answer the questions and fax or mail this form back to Allied Telesyn International
Corp. The mailing address and fax number are at the bottom of the page. Your comments are
valuable when we plan future revisions of the guide.

I found the following the most valuable _______________________________________

______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________

I would like the following more developed _____________________________________

______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________

I would find the guide more useful if _________________________________________

______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________

Please fax or mail your feedback. Fax to 1-206-481-3790. Or mail to:
Allied Telesyn International Technical Communications Department
19015 North Creek Parkway, #200
Bothell, WA 98011 USA

45

Appendix E

Where To Find Us

For Technical Support or Service

Location Phone Fax

Asia

Singapore, Taiwan, Thailand, Malaysia,
Indonesia, Korea, Philippines, China, India

Australia

Australia, New Zealand

France

France, Belgium, Luxembourg, The Netherlands,
Middle East, Africa

Germany

Germany, Switzerland, Austria, Eastern Europe

Hong Kong ([phone] ([phone]

Italy

Italy, Spain, Portugal, Greece, Turkey, Israel

Japan ([phone] ([phone]

North America

United States, Canada, Mexico, Central America,
South America

United Kingdom

United Kingdom, Denmark, Norway, Sweden,
Finland, Iceland

Technical Bulletin Board Service 1 [phone]

CompuServe Go ALLIED

World Wide Web http://www.alliedtelesyn.com

([phone] ([phone]

[phone] [phone]

([phone] ([phone]

([phone] ([phone]

([phone] ([phone]

1 [phone] 1 [phone]

([phone] ([phone]

For Information Regarding Allied Telesyn International Corp.

Allied Telesyn International Corp.

19015 North Creek Parkway Suite 200
Bothell, WA 98011
Tel: [phone]
Fax: [phone]

Allied Telesyn International Corp.

950 Kifer Road
Sunnyvale, CA 94086
Tel: [phone] (USA and Canada)
Fax: [phone]

47

Where To Find Us

For Sales Information

Australia
Lindfield, NSW

Tel: [phone], Fax: [phone]

Canada
Rexdale, Ontario

Tel: [phone], Fax: [phone]

Richmond, British Columbia

Tel: [phone], Fax: [phone]

England
Abingdon, Oxon

Tel: [phone], Fax: [phone]

France
Les Ulis

Tel: [phone], Fax: [phone]

Germany
Berlin

Tel: [phone], Fax: [phone]

Freising

Tel: [phone], Fax: [phone]

Hong Kong
Wanchai

Tel: [phone], Fax: [phone]

Italy
Milano

Tel: [phone], Fax: [phone]

Japan
Machida-shi, T okyo

Tel: [phone], Fax: [phone]

Yodogawa-ku, Osaka

Tel: [phone], Fax: [phone]

Singapore

Tel: [phone], Fax: [phone]

United States
Scottsdale, AZ

Tel: [phone] Fax: [phone]

Los Angeles, CA

Tel: [phone], Fax: [phone]

Mission Viejo, CA

Tel: [phone], Fax: [phone]

San Diego, CA

Tel: [phone], Fax: [phone]

Santa Ana, CA

Tel: [phone], Fax: [phone]

Clearwater, FL

Tel: [phone], Fax: [phone]

Norcross, GA

Tel: [phone], Fax: [phone]

Reading, MA

Tel & Fax: [phone]

Eden Prairie, MN

Tel: [phone], Fax: [phone]

St. Louis, MO

Tel: [phone], Fax: [phone]

Dover, NH

Tel: [phone], Fax: [phone]

Plaistow, NH

Tel: [phone], Fax: [phone]

Portsmouth, NH

Tel: [phone], Fax: [phone]

Morrisville, NC

Tel: [phone], Fax: [phone]

Lake Oswego, OR

Tel: [phone], Fax: [phone]

Austin, TX

Tel: [phone], Fax: [phone]

Dallas, TX

Tel: [phone], Fax: [phone]

San Antonio, TX

Tel: [phone]

Vienna, V A

Tel: [phone], Fax: [phone]

48

Appendix F

Index

Numerics

50 Ω terminator switch 4, 6

802.3 transceiver 5

A

ambient temperature 7
application specific integrated circuit

(ASIC) 3

B

backbone

10Base5 29
fiber optic 30

backbone network ports 2

C

cabling

10Base2 4, 6, 17, 19
10Base2 (thin) ethernet 19
10Base5 5, 9, 15, 17
10Base5 (thick) ethernet 18
10Base-FL 30
10Base-T 8, 9, 13, 15, 17, 20,

27
5 - 4 - 3 rule 35
AUI drop 18
connectors 33
crossover 34
data-quality 20
four repeater rule 24
straight-through 33
voice-quality 20

connections 9
connectivity 15
connectors

power 15
RG58U 19
UTP (RJ45) 20

D

data terminal equipment 12

E

external transceiver 8

F

features 3

auto partitioning 3
jabber lock-up protection 3
link integrity 3
regeneration 3

G

ground 4

I

indicators

activity 1
collision 1
hub status 12
link 1
link ok 9, 11, 13
port 10
power 1, 8
receive 1, 11

installation 7

power 7
quick 8
ventilation 7

L

LED 1
local area network (LAN) 1

M

Maximum segment length 4
media dependent interface (MDI) 26
medium attachment unit (MAU) 19, 20

N

network interface controller (NIC) 20

O

overview 1

P

pins

10BASE-T pin assignments 32

ports

49

Index

10Base2/AUI backbone switches 5
AUI 17
AUI network 9
backbone 17
backbone network 4
BNC 19
BNC network 9
network backbone 15
RJ45 9
uplink 2, 8

power conditioners 15
product description 1

R

RJ45 network ports 2

S

segmentation 3
signal quality error (SQE) 8
site requirements 7
specifications

10Base-T Network 17
certification 32
connector ports 31
diagnostic LEDs 32
electrical 31
environmental 31
physical 31

surface mount technology (SMT) 3
switches

backbone enable 5, 6
BNC terminator 24
MDI/MDI-X 27
media select 5, 6

T

technical support services

bulletin board xx
compuserve xx
compuserve forum xxi
contacting xx
electronic mail xx
internet mail xx, xxi

topology 23

backbone network 26
bussing 29

transceiver 6

U

unshielded twisted pair (UTP) 2

V

ventilation 7

W

wiring 4, 5, 6, 8, 9, 13, 15, 17,

18, 19, 20, 24, 27, 30,
33, 34, 35

50