Motorola MB7621 User manual

Model MB7621
24x8
Cable Modem
Quick Start

2
Packaged with your modem
Power Cube
Coax Wrench
Ethernet Cable
Velcro®Cable Tie
Para una Guía de Inicio Rápido en español, por
favor vaya a
www.motorolanetwork.com/MB7621ir

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Let’s get started
If you don’t have cable modem service, please order that from
your cable service provider.
Now connect your modem as shown on the next panel.
Connecting to a Coax Cable
On the next panel you’ll need to connect your
modem to a “live” coax cable. Sometimes a cable
will already be available. Sometimes there’s a coax
wall jack available, and you connect to the jack
with a coax cable. Your modem can also share a
coax cable attached to a TV by using a coax
splitter. Please note that a splitter sometimes
reduces a cable modem’s speed; so if you need to
use a splitter, use a 2-way splitter whose top
frequency is at least 1000 MHz.

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ON/OFF button
POWER
Connect the supplied power
cube between the power jack
and an electrical outlet.
COAX
Connect a “live” coax
cable to the modem’s COAX
connector as discussed
above. (Tighten the nut so it’s
finger tight. You may
want to use the supplied
wrench. Make the connection
snug but not over-tight.)
RESET button
ETHERNET (LAN)
Connect this port to a
computer. Alternatively, you
can connect to a WiFi router -
see
If You Want to Connect a
Router
, below.

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Prepare to activate
By now you should have:
•Subscribed to cable Internet service.
•Connected your cable modem.
•Powered up your cable modem. To do this, the On/Off button
needs to be On. Wait for the online connection light ( ) to
stop flashing and remain solidly lit. This may take up to 15
minutes.
You should have a recent cable bill handy because it has your
account number and you’ll probably need that.
If you’re asked for information about your cable modem, you
can find this on the label on the bottom of the modem.
Activate
For some service providers, you activate by calling them.
Many service providers including Comcast and Cox prefer that
you activate by first opening the Web browser of a computer
that’s plugged into the MB7621’s Ethernet port. Once you’ve
opened the browser, try to go to www.motorola.com . This
should bring you to the service provider’s activation page.

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For Comcast XFINITY Users Only:
If the activation page does not appear, please go to
xfinity.com/activate for more information and to activate
your modem.
Here is a list of phone numbers for some major cable
service providers. (Note that this list is subject to
change.)
Comcast
1 (800) XFINITY
Cox
1 [phone]
Bright House (Spectrum)
1 [phone]
Cable One
1 [phone]
Charter Spectrum
1 (855) 757
-7328
MediaCom
RCN
1 (844) 987
-3260
1 [phone]
Suddenlink
1 [phone]
Time Warner (Spectrum)
WOW!
1 (855)
707-7328
1 [phone]
Once your MB7621 is activated either online or by
phone, your service provider will provision your
MB7621 service. Typically this takes less than 5
minutes, but in some cases this may take 30 minutes
or longer to complete.
Once you have activated, you should have Internet access for
whatever’s plugged into your cable modem. Congratulations!
If your cable modem is NOT working, see Troubleshooting
Tips below.
Note: You can connect this device to a WiFi
router, computer, HDTV, game station, or other
Ethernet-capable device. This product does not
include a router, WiFi, or telephone capability.

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If You Want to Connect a Router
Most users will connect a WiFi router to the MB7621. A
wireless router lets multiple devices (computers,
smartphones, tablets, video devices, game stations…) share
your cable modem’s Internet connection, either wirelessly
or through a direct Ethernet connection. Connecting a
router to the MB7621 may be made initially, before
activating the cable modem, or it may be done after the
cable modem has been activated from a PC.
1. The cable modem and the router should both be
powered off.
2. Plug one end of the cable modem’s Ethernet cable into
the Ethernet jack of your modem, and plug the other
end of the cable into the router’s WAN port. (You may
need to disconnect the cable from your computer first.)
3. Power-up the cable modem. Wait for the ONLINE light
( ) to be solidly lit.
4. Power-up the router. Wait for the router to complete its
power-up sequence.
5. The LAN light on your modem should be lit to show
the Ethernet connection to your router.
6. Follow your router’s instructions for setting up the
router and connected devices.
If you haven’t already activated your Internet service, do
that now. (See Prepare to Activate on page 5.) Using a
computer or other device connected to the router, try
connecting to the Internet. If it works, Congratulations!
Installation is complete.

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MB7621 Lights
LIGHT
COLOR
DESCRIPTION
Power
Green
ON:
Cable modem power on
OFF:
Cable modem power off
Downstream
Green or
Blue
Green
Blinking:
Scanning for DS channel
Green
ON:
Connected on
1 downstream channel
Blue
Blinking:
Negotiating
bonded channel(s)
†
Blue ON:
Bonded with 2 or more
channels
Upstream
Green or
Blue
Green
Blinking:
Ranging in progress
Green
ON:
Connected on 1 channel
Blue
Blinking:
Negotiating bonded
channel(s)
†
Blue ON:
Bonded with 2 or more channels
OFF:
Upstream not connected
Online
Green
Blinking:
Trying to go online
Green:
Online
OFF:
Offline
LAN
Green
Blinking:
Ethernet data is flowing
Green:
Ethernet port linked
Rear Panel
Ethernet LAN
ports
Green or
Amber
Blinking:
Ethernet data is flowing
Green:
Connected at 1 Gbps
Amber:
Connected at 10 or 100 Mbps
OFF:
No connection
†If a blue Upstream or Downstream light blinks continuously, this indicates
partial service (at least one designated channel has not completed bonding).
You should still get high Internet speeds, but your service provider may want
to know so they can adjust their network.

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Troubleshooting Tips
What if I can’t make an Internet connection right after
installation?
•First turn your cable modem off for at least 8 seconds, then
on, to see if that fixes the problem.
•Check the connections you’ve made to your cable modem –
power, Ethernet, and coax. Are those connections good? Be
sure that the coax cable connection is tight enough, possibly
using the coax wrench.
•Check that the modem’s power cube is plugged into a live
outlet, and that the Ethernet cable is connected securely.
•Make sure that your coax cable is live. You can check that by
using it with a TV.
•Check that you provided the correct setup information to your
cable service provider.
•Contact your cable service provider to make sure they’ve
turned on your Internet service.
What if my cable modem has been working, and then stops
working?
•First turn your cable modem off for at least 8 seconds, then
on, to see if that fixes the problem.
•If the modem’s lights don’t come on, check that the modem is
getting power from its power cube and that the modem’s
power button is on.
•Check your cable modem cables.
•Check with your service provider. Sometimes there’s a service
outage or some other service issue. Sometimes a service
outage also affects your TV service, so check that.
What if I’m getting Internet service but my speed is
disappointing?
•Be sure you know what speed you’re paying for.
•Check the speed with a computer plugged into the modem.
Use one of the tools found when you search the phrase:
broadband speed test.

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•No matter who your service provider is, check Comcast
XFINITY’s Internet Minimum System Recommendations here:
https://www.xfinity.com/support/internet/requirements-
to-run-xfinity-internet-service/
•If you get good speed when a computer’s plugged into the
modem, you may have a router problem.
•Some video streaming services get bottlenecked, especially at
busy times like after dinner. See whether you have the speed
problem at less busy times.
•Try connecting your cable modem nearer to where the coaxial
cable comes into your home. This lets you see whether your
home’s cabling is a problem.
•If you’re using a splitter with your cable modem, try the cable
modem without the splitter to see if that helps. If it does, you
may need to get a better splitter, one with a top frequency of
at least 1000 MHz.
•Make sure your computer’s or router’s LAN port supports
gigabit rates (1000BT or GE). You will need this to match
service speeds of 100 Mbps or greater.
What if I'm told that my cable modem isn't approved for
my cable modem service?
That’s probably not true. Leading cable service providers have
a list of certified cable modems, and you can check the list for
your service provider. You can also find information about
certifications at www.motorolanetwork.com/services
Do you have any other questions? We have lots more
information at www.motorolanetwork.com/mentor