NETGEAR EN308TC - 8 Port 10 Base-T Hub User manual

Model EN308
TC
Ethernet Hub Installation Guide
Start Here
Congratulations on your purchase of the NETGEAR
™
Model EN308
TC
Ethernet hub This hub delivers standards-based, plug-and-play networking
solutions for small businesses, home offices, and low-density workgroups of
larger companies
Features
The Model EN308
TC
hub has the following features:
• Eight 10BASE-T network ports (RJ-45) that provide 10 megabit per second
(Mbps) networking using simple unshielded twisted pair (UTP) wiring
• Coaxial BNC backbone support for connecting to an existing Ethernet
segment or external transceiver, or for network expansion by connecting
multiple hubs together using coaxial cabling
• Built-in LED indicators for at-a-glance status checks by networks ports
• Uplink port for connecting to other hubs using simple straight-through
cables
• Front-panel LED indicators to monitor overall hub status
• Plug-and-play installation with no software to configure
• Complete hub functions including packet retiming, collision detection,
preamble regeneration, and fragment extension
• Automatic partitioning and reconnection of a port that has excessive
collisions or is jabbering
• Automatic polarity detection for recognizing and correcting incorrect
polarity on the receive pair
• Compact design, enabling easy tabletop or rack-mounting installation
• Internal power adapter
• Limited five-year warranty
Start Here
Features

Model EN308
TC
Ethernet Hub Installation Guide
Package Contents
Verify that your package contains the following:
• Model EN308
TC
hub
• Mounting kit (for wall installation)
• BNC T-connector and BNC 50 Ω terminator
• This installation guide
• Warranty & Owner Registration Card
• Support Information Card
• Power cord
9125FA
Power
cord
Mounting kit
Model EN308
TC
hub
100M 10M
87654321
On = Link Blinking = Activity
Normal/Uplink
BNC
100-240 VAC, 50-60Hz 0.2A max.
50
OHM
BNC 50
terminator and
BNC T-connector
Installation guide,
Warranty & Owner
Registration Card,
and Support
Information Card
Package Contents

Model EN308
TC
Ethernet Hub Installation Guide
Product Illustration
Front Panel
The front panel of the Model EN308
TC
hub contains LEDs that monitor the
activity status of the hub
For ease of use, the front panel 10BASE-T LEDs that indicate link, receive, or
partition activity are duplicated on the 10BASE-T ports on the rear panel Use
the rear panel LEDs when setting up the device, and use the same LEDs on the
front panel for monitoring the ports when the hub is positioned in place and set
up
Front Panel LEDs
The table below describes the activity of the front panel LEDs
Label Color Activity Description
Pwr (Power) Green On Power is supplied to the hub.
Col (Collision) Amber Blinking Data collision is occurring on the network. Note
that occasional collisions are normal.
10BASE-T
LEDs
Link/Receive
(For ports 1
through 8)
Green On The link between this port and the connected
port is good.
Blinking There is incoming data on the port.
Partition Amber On The port is partitioned because of excessive
collisions.
BNC LEDs
Rx Green Blinking There is incoming data on the BNC port.
Partition Green On The BNC port is partitioned because of
excessive collisions.
9117FA
PWR COL
1234
On=Link, Blinking=Receive
Partition
5678
EN308TC
MODEL
PORT
10 Mbps
Ethernet Hub
8
Rx
Partition
COL
(Collision)
LED
PWR
(Power)
LED
BNC Partition
LED
BNC Rx
LED
10BASE-T
LEDs
Product Illustration

Model EN308
TC
Ethernet Hub Installation Guide
Rear Panel
The rear panel of the Model EN308
TC
hub has eight RJ-45 10BASE-T ports, a
BNC port that you can use to connect to a backbone network or other PCs using
thin coaxial cable, and a Normal/Uplink push button
The rear panel also includes a DC power receptacle
RJ-45 10BASE-T Network Ports with Built-in LEDs
Two LEDs—the Link/Rx (Receive) LED and the Part (Partition) LED—are
built into each 10BASE-T port
The table below describes the activity of the LEDS
Label Color Activity Description
Link/Rx
(Located in the top
left corner of each
10BASE-T port)
Green On The link between this port and the connected
port is good.
Blinking There is incoming data on the port.
Part
(Located in the top
right corner of each
10BASE-T port)
Amber Blinking The port is partitioned because of excessive
collisions.
9118FA
BNC port Power receptacle
100M 10M
87654321
On = Link Blinking = Activity
Normal/Uplink
BNC
100-240 VAC, 50-60Hz 0.2A max.
Normal/Uplink
push button
10BASE-T
ports
8724EC
Link/Rx
(Receive)
LED
Part
(Partition)
LED

Model EN308
TC
Ethernet Hub Installation Guide
Normal/Uplink Push Button for Port 8
The Normal/Uplink push button allows you to select Normal (MDI-X) wiring
for direct PC connection The push button also allows you to select Uplink
(MDI) wiring for connection to another hub or to a switch through port 8 on the
Model EN308
TC
hub This uplink configuration eliminates the need to use a
crossover cable The other 10BASE-T ports are permanently configured for
normal wiring for connection to a PC
Installation Procedures
1. Prepare the Site
Before you begin installing your Model EN308
TC
hub, prepare the installation
site Make sure your operating environment meets the operating environment
requirements of the equipment
2. Install the Hub
To install your hub on a flat surface, you do not need any special tools Be sure
the hub is positioned with at least 2 inches of space on all sides for ventilation
To install the hub on a wall, measure the distance between the mounting holes
on the back of the hub and mark the wall to match the location of the mounting
holes on the hub At the marked location, screw into the wall the two screws that
you received with the mounting kit included in your package contents Be sure
to choose a location that is near the devices to be connected, is close to an
electrical outlet, and provides at least 2 inches of space all around the hub for
ventilation
Characteristic Requirement
Temperature Ambient temperature between 0
° and 40 ° C (32 ° and 104 ° F).
No nearby heat sources such as direct sunlight, warm air
exhausts, or heaters.
Operating humidity Maximum relative humidity of 90%, noncondensing.
Ventilation Minimum 2 inches (5.08 cm) on all sides for cooling.
Adequate airflow in room or wiring closet.
Operating
conditions At least 6 feet (1.83 m) to nearest source of electromagnetic noise (such as photocopy machine or arc welder).
Service access Minimum 12 inches (19.68 cm) front and back for service access
and maintenance.
Front and back clearance for cables and wiring hardware such as
punchdown blocks.
Power Adequate power source within 6 feet (1.83 m).
Wiring hardware Wiring hardware, such as punchdown blocks or patch panels,
should be complete before installing the hub.
Prepare the Site
Installation Procedures
Install the Hub

Model EN308
TC
Ethernet Hub Installation Guide
3. Connect a PC to the Hub
You can connect PCs, Apple Macintosh computers, UNIX workstations, or any
device equipped with a 10BASE-T Ethernet interface to the RJ-45 ports on your
hub by using twisted pair Ethernet cables
To connect any of the RJ-45 ports on your hub to a PC, use a regular straight-
through UTP cable If you are connecting using port 8 on the Model EN308
TC
hub, set the Normal/Uplink push button to Normal
Note: Ethernet specifications limit the cable length between your PC
or server and the hub to 328 feet (100 meters) in length
Normal/Uplink
12345678
9126FA
Connect a PC to the Hub

Model EN308
TC
Ethernet Hub Installation Guide
4. Connect the Hub to a Network
Cascading refers to connecting hubs together to increase the number of ports or
the number of users supported on the network The 10BASE-T ports can be used
to cascade hubs together
The twisted pair cable extended from a 10BASE-T port (or UTP port) is called a
twisted pair segment and can be up to 100 meters (m) in length The 10BASE-T
ports, with the exception of port 8, are MDI-X (or Normal) ports Use the
following table as a guide for selecting the appropriate network cable
Set the Normal/Uplink Push Button
If you are connecting to port 8 on the Model EN308
TC
hub, use the following
table Determine the type of cable to use and how to set the Normal/Uplink push
button
Connecting Port
on the Hub Connecting Device Cable Used
Ports 1–7 PC, server, or router Straight-through cable
Ports 1–7 Hub or switch Crossover cable
Connecting Port Connecting Device Cable Used
Port 8 set to Normal PC, server, or router Straight-through cable
Port 8 set to Uplink Hub or switch Straight-through cable
Connect the Hub to a Network

Model EN308
TC
Ethernet Hub Installation Guide
Cascade the Hub Using the 10BASE-T Ports
The following illustration shows cascading hubs together in a hierarchical star
through the 10BASE-T ports and indicates the setting of the Normal/Uplink
push button on each hub
The following illustration shows cascading Model EN308
TC
hubs together
daisy-chain style Refer to the illustration for setting the Normal/Uplink push
button on each hub
Note: Ethernet specifications limit the number of hubs with twisted
pair links in any communication path to five, as shown in the example
When PC “A” communicates with PC “B,” the communication path
goes from hub 4 to hub 2, to hub 1, to hub 3, and then to hub 5 (or five
paths)
100M 10M
87654321
On = Link Blinking = Activity
Normal/Uplink
BNC
100-240 VAC, 50-60Hz 0.2A max.
1234 56 78
Pwr
Col
EN108
TP
10 BASE-T HUB
1234 56 78
Pwr
Col
EN108
TP
10 BASE-T HUB
9122FA
AB
Model EN104
hub Model EN104 hub
4
23
1
5
Model EN308TC hub
Model EN108
hub Model EN108 hub
Uplink
Normal
UplinkUplink
Uplink
100M 10M
87654321
On = Link Blinking = Activity
Normal/Uplink
BNC
100-240 VAC, 50-60Hz 0.2A max.
100M 10M
87654321
On = Link Blinking = Activity
Normal/Uplink
BNC
100-240 VAC, 50-60Hz 0.2A max.
100M 10M
87654321
On = Link Blinking = Activity
Normal/Uplink
BNC
100-240 VAC, 50-60Hz 0.2A max.
9123FA
Normal
Uplink
Uplink

Model EN308
TC
Ethernet Hub Installation Guide
Connect to a Network Using the BNC Port
The BNC port on the rear panel of the hub is used for connecting to a thin
coaxial segment You can connect other Model EN308
TC
hubs, servers,
workstations, or other devices to the BNC port A BNC T- connector is inserted
in the port, and the BNC 50 Ω terminator terminates the connection at each end
device By using the BNC port for cascading, you treat each connected hub as
just another node on the coaxial segment
The separation marks in the coaxial cable between the hubs in the following
illustration represent the incorporation of other devices and show that
interconnection is not limited to hubs
Note: Ethernet specifications limit a BNC segment to 30 BNC
connections, specify a minimum of 1 64 feet (0 5 m) between any two
stations, and limit segments to 607 feet (185 m) in length
Normal/Uplink
12345678
Normal/Uplink
12345678
Normal/Uplink
12345678
9124FA
BNC 50 terminator
BNC T- connector
BNC 50 terminator

Model EN308
TC
Ethernet Hub Installation Guide
5.Verify the Installation
To complete the installation, connect the power cord first to the power receptacle
on the hub rear panel and then to the power outlet on the wall When power has
been applied to the hub:
• The green Pwr (Power) LED on the front panel is on
• The green Link/Receive LED on each connected port is on
If there are any problems, refer to “Troubleshooting Information ” Refer to the
troubleshooting table and the information that follows to troubleshoot your hub
Network Interface Cards
Make sure the network interface cards installed in the workstations are in
working condition and the software driver has been installed
Hub Integrity
If required, verify the integrity of the hub by resetting it Turn power to the hub
off and then back on If the problem continues and you have completed all the
preceding diagnoses, contact NETGEAR Customer Support For the phone
number of the representative in your area, see the Support Information Card
included in your package contents
Verify the Installation

Model EN308
TC
Ethernet Hub Installation Guide
Troubleshooting Information
Symptom Cause Solution
Amber Col LED
blinks. Thereisdata collision on the network. Data collision is normal on Ethernet networks.No action is required.
Amber Col LED
blinks excessively. Thereis datacollision on
the network because
the network is
extremely busy
or defective devices
are connected on the
network that cannot
detect network traffic
or collision.
Make sure connected devices are operating in half-
duplex mode.The hub is not compatible with devices
that operate in full-duplex mode.
If you suspect that there might be a defective device
on the network, disconnect devices one at a time to
isolate the defective unit on the network.
If the network is extremely busy, you may have to
segment the network with an Ethernet switch such as
a NETGEAR Ethernet switch or to upgrade your
network to Fast Ethernet operation.
Wrong or miswired
cables are used. Make sure the correct UTP cables are used. See the tables in the installation section of this guide for cable
use and Normal/Uplink push button information.Note
that home telephone cables can cause a collision
condition and cannot be used in place of UTP cables.
Link/Rx LED on
front panel or Link/
Rx green LED on
rear panel is off
when a cable is
attached.
The port is not
detecting a
successful link.
Check for a bad cable, cable pairs that are not
correctly wired, or loose connectors.Make sure that
there is power to both the hub and the Ethernet
transceiver on the connected device.
Link/Rx LED on
front panel or Link/
Rx green LED on
rear panel is not
blinkingwhenthere
is data
transmission.
The port is not
detecting data
transmission.
Check for a bad cable, cable pairs that are not
correctly wired, or loose connectors.Make sure that
there is power to both the hub and the Ethernet
transceiver on the connected device.
Green Rx LED on
the BNC port is not
on when the port is
connected.
The port is not
detecting a
successful link.
Make sure that each segment is terminated with a
BNC 50
Ω
terminator at both ends. Check for a bad
cable.
Green Rx LED on
the BNC port is not
blinkingwhenthere
is data
transmission.
The port is not
detecting data
transmission.
Check for a bad cable or loose connectors. Make
sure that there is power to both the hub and the
connected device.
Troubleshooting Information

Model EN308
TC
Ethernet Hub Installation Guide
Twisted Pair Cables
Twisted Pair Cables
For two devices to communicate, the transmitter of each device must be
connected to the receiver of the other device The crossover function is usually
implemented internally as part of the circuitry in the device Most ports on
switches and repeaters have media dependent interfaces with crossover ports
These ports are referred to as MDI-X or Normal ports Computer and
workstation adapter cards are usually media-dependent interface ports referred
to as MDI or Uplink ports The figures above illustrate the use of straight-
through and crossover twisted pair cables
Straight-through
twisted pair cable
Crossover
twisted pair cable
8146EC
Tx
Uplink or
MDI port Normal or MDI-X port
Normal or
MDI-X port Normal or MDI-X port
Rx
1
2
3
6Tx
Rx
1
2
3
6
1
2
3
6
1
2
3
6
Tx
Rx
Tx
Rx
Twisted Pair Cables

Model EN308
TC
Ethernet Hub Installation Guide
RJ-45 Connector
The RJ-45 connector (shown in the illustration with an RJ-45 plug) is used to
connect workstations, hubs, and switches through unshielded twisted pair cable
The RJ-45 connector accepts four-pair Category 3 or Category 5 UTP cable
Only two pairs are used for 10BASE-T wiring
BNC Connector
The BNC connector for the hub supports 10 Mbps data transmission and
connects the hub to other devices
The BNC T-connector and the 50 Ω terminator enable the BNC port on the hub
to connect a thin coaxial segment
RJ-45 Connector
Pin Assignment Normal Assignment:
Port 1 - 8 Uplink Assignment: Port 8
1 Input Receive Data + Output Transmit Data +
2 Input Receive Data - Output Transmit Data -
3 Output Transmit Data + Input Receive Data +
6 Output Transmit Data - Input Receive Data -
4, 5, 7, 8 Not used Not used
711EA
18
12345678
8149EA
12
Center conductor Ground shield
BNC connector
8150FA
50
OHM
50 Ωterminator
BNC T-connector

Model EN308
TC
Ethernet Hub Installation Guide
Technical Specifications
General Specifications
Network Protocol and Standards Compatibility
IEEE 802.3i, 10BASE-T, 10BASE-2, 10BASE-5 Ethernet
Data Rate 10 Mbps, Manchester encoded
Interface 10BASE-T ports (RJ-45), BNC port
Power Consumption 3.5 W
Physical Specifications
Dimensions: 3.37 by 4.0 by 1.1 in.
94 by 101 by 28 mm
Weight: 0.74 lb (0.34 kg)
Environmental Specifications
Operating temperature: 0 ° to 40 ° C (32 ° to 104 ° F)
Operating humidity: 90% maximum relative humidity, noncondensing
Electromagnetic Emissions
CE mark, commercial
FCC Part 15 Class A
EN 55 022 (CISPR 22), Class A
VCCI Class 1 ITE
Electromagnetic Susceptibility
CE mark, commercial
Electrostatic discharge (ESD): IEC 801-2, Level 2/3/4
Radiated electromagnetic field: IEC 801-3, Level 2
Electrical fast transient/burst: IEC 801-4, Level 2
Electrical surge: IEC 801-5, Level 2
Technical Specifications

Model EN308
TC
Ethernet Hub Installation Guide
© 2000 by NETGEAR, Inc All rights reserved
Trademarks
NETGEAR™ is a trademark of NETGEAR, Inc Windows® is a registered trademark of
Microsoft Corporation Other brand and product names are trademarks or registered trademarks of
their respective holders Information is subject to change without notice All rights reserved
Statement of Conditions
In the interest of improving internal design, operational function, and/or reliability, NETGEAR
reserves the right to make changes to the products described in this document without notice
NETGEAR does not assume any liability that may occur due to the use or application of the
product(s) or circuit layout(s) described herein
Certificate of the Manufacturer/Importer
It is hereby certified that the NETGEAR Model EN308
TC
hub has been suppressed in accordance
with the conditions set out in the BMPT-AmtsblVfg 243/1991 and Vfg 46/1992 The operation of
some equipment (for example, test transmitters) in accordance with the regulations may, however,
be subject to certain restrictions Please refer to the notes in the operating instructions
Federal Office for Telecommunications Approvals has been notified of the placing of this
equipment on the market and has been granted the right to test the series for compliance with the
regulations
Voluntary Control Council for Interference (VCCI) Statement
This equipment is in the first category (information equipment to be used in commercial and/or
industrial areas) and conforms to the standards set by the Voluntary Control Council for
Interference by Data Processing Equipment and Electronic Office Machines that are aimed at
preventing radio interference in commercial and/or industrial areas
Consequently, when this equipment is used in a residential area or in an adjacent area thereto,
radio interference may be caused to equipment such as radios and TV receivers
Federal Communications Commission (FCC) Compliance Notice:
Radio Frequency Notice
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 If it is not
installed and used in accordance with the instruction manual, it may cause harmful interference to
radio communications Operation of this equipment in a residential area is likely to cause harmful
interference, in which case users will be required to take whatever measures may be necessary to
correct the interference at their own expense
EN 55 022 Statement
This is to certify that the NETGEAR Model EN308
TC
hub is shielded against the generation of
radio interference in accordance with the application of Council Directive 89/336/EEC, Article 4a
Conformity is declared by the application of EN 55 022 Class A (CISPR 22)
Canadian Department of Communications Radio Interference Regulations
This digital apparatus (NETGEAR Model EN308
TC
hub) does not exceed the Class A limits for
radio-noise emissions from digital apparatus as set out in the Radio Interference Regulations of
the Canadian Department of Communications
Règlement sur le brouillage radioélectrique du ministère des Communications
Cet appareil numérique (NETGEAR Model EN308
TC
hub) respecte les limites de bruits
radioélectriques visant les appareils numériques de classe A prescrites dans le Règlement sur le
brouillage radioélectrique du ministère des Communications du Canada
This is a Class A product In a domestic environment, this product may cause radio
interference, in which case the user may be required to take appropriate measures

Model EN308
TC
Ethernet Hub Installation Guide
NETGEAR, Inc
4500 Great America Parkway
Santa Clara, CA 95054
USA
Phone: 1-888-NETGEAR
E-mail: support@NETGEAR com
www NETGEAR com