NOTE: Current Federal Communications Commission (FCC)
regulations limit your maximum connection rate to 53 Kbps.
You may have too many telephone devices connected to the phone line. To
help your modem achieve the best connection possible, remove all extra
devices and their cables from the phone line when the modem is in use. This
includes extension phones, answering machines, and especially cordless phone
re-charger bases.
The quality of your local loop (the copper line between the customer
premises and the phone company’s central office) has a great effect on any
modem’s connect rate. Impairments such as loaded loops, long local loops
(in rural areas), and DLCs (Digital Loop Carriers) prevent the modem from
connecting at V.90 and V.92 (56kbps) data-rates. Digital Loop
Carriers are sometimes used in the local loop instead of direct copper pairs
in new neighborhoods or rural areas.
Communications and telephony applications often rely on settings stored in
the Windows Registry to operate the modem. If any aspect of the modem's
installation is corrupt (driver files were accidentally deleted, or registry
entries corrupted) your communications applications may have problems accessing
the modem.
The best course of action is to run Modem Helper. This action will replace any missing files and
re-write all the modem registry entries.
If the modem is unable to dial try the following suggestions to resolve the
problem:
Make sure you have a high quality telephone cable connecting your modem to
the telephone jack.
Ensure that all handsets within the home are on-hook before proceeding to
dial.
Ensure that you place any necessary dialing prefixes in the dial string.
For example dialing a "9" to get an outside line.
If you have a "Digital Line Protection" applet, make sure it is
running prior to your dial attempt. This applet will alert you to the
presence of a digital phone line which may damage your modem.
Your modem's regional settings may not be compatible with your current
location. For example, if you normally use your modem in the U.S. and
then travel to Germany, the German dial tone may not be recognized since the
modem expects a U.S. dial tone. Check the "Dialing Rules" settings
in the "Modem and Dialing Properties" applet in the Windows
Control Panel. If necessary, set up a new "Location" that matches
your physical location.
There are many reasons why the modem will drop a connection. The remote modem
may also be the cause of the disconnection. The following list offers
suggestions to keep this from happening:
Place a "*70" in your dialing string to prevent call waiting
tones from disrupting your session.
Ensure that all the other handsets connected to the phone line are
on-hook.
If there is no activity on the connection, the local modem or remote modem
may automatically shut down the connection. This may also be due to the
telephony/communications application you are using. There may be a setting
to change this. Search your applications help files for
"Inactivity Timer".
The disconnect may be caused by "noise" on the phone line. Noise
often causes modems to "retrain", but if noise persists during the
retrain, the modem may be unable to retain the connection. In this case, try
your call again, try a different phone extension, check your telephone
cables, and if needed call your telephone service provider for assistance in
improving your line conditions.
Other devices might be trying to access the phone line while your modem is
connected. Devices such as TV set top boxes or fax machines may be the
source of these problems. Disconnect these additional devices to see if they
are the cause of your disconnect problems.
The modem speaker may be turned off by default. Your communications/telephony
application may be turning the modem speaker off by default.
Search your comm app's settings for modem speaker settings/volume.
Optionally, you may place "atm1" in the "Extra
Initialization Commands" under the "Advanced" tab in the
Modem Properties applet (in the Windows Control Panel). Keep in mind that
your communications/telephony application might override this setting.
There are many reasons why the modem may not connect to the Internet.
Please check if you are dialing to correct number. You can verify that a
remote modem is answering your modem by using a handset to dial the ISP's
number. If a remote modem is answering, you will hear high pitched whistles
and tones.
Please check if the number you are dialing supports the modem standard you
desire to use. For example, the phone number you are dialing may only
support V.34 (28.8kbps) while your modem is expecting a V.90 connection
(56k).
The number you are dialing may be busy. If this is the case, try your call
at a later time.
Poor line conditions may be preventing your modem from connecting. In this
case, try your call again, try a different phone extension, check your
telephone cables, and if needed call your telephone service provider for
assistance in improving your line conditions.
You may be performing an action with the PC that is aborting the dialing
process. For instance, hitting a key while using Hyperterminal to dial
causes a "key abort", thus cancelling the dialing attempt. Please
check that you are not performing any actions with your
communications/telephony application that causes it to abort the dialing
attempt.
The username and password you provided for login may be incorrect. In this
case, the server may force the modem to disconnect.
If your network settings are not compatible with the ISP you are dialing,
the ISP may disconnect you shortly after establishing a connection. For
example, your DNS settings may not be correct. Please refer to your ISP's
required network settings to ensure you have configured your "Dial-Up
Networking" settings.
The Conexant MDC Modem is designed to connect at the connect rate
which will maximizes modem throughput. Generally this means that the modem will
connect in V.90 modem, falling back to V.34 if the line cannot sustain a V.90
connection.
There are many factors that cause will cause the modem to connect at a lower
than expected data rate.
Long distance between your location and the phone company's central
office.
DLC's in the local loop (used in newer neighborhoods to aggregate phone
lines into a digital trunk line).
Noisy local loops or other devices on the phone line which cause noise.
There are two different connect rates that may be reported by your
communications applications as "connect rate". Additionally,
throughput is used to describe modem performance.
DCE Rate - DCE stands for Data Communication Equipment. The DCE rate is
the actual connect rate the modem establishes depending on line conditions.
For a V.92 modem, the maximum downstream data rate is 56k*. The DCE rate may
vary from session to session as line conditions may change.
DTE Rate - DTE stands for Data Terminal Equipment. The DTE rate defines
the data rate of the serial or modem port. The DTE rate is the data rate at the interface between the computer and the modem. It is usually reported as
115,200 bps. The reported DTE rate is generally constant from session to
session.
Throughput - Throughput is the actual rate of data transfer over the phone
line. Once the modem is connected and the connect rate is established, data
will be received and transmitted at a rate depending on the compression and error
correction protocols established during the modem's handshaking sequence.
DCE Rate is more useful than the DTE rate when judging modem
performance. Moreover, Data Throughput is more useful than DCE rate when judging modem
performance.
If you are not satisfied with the modem's performance, there are various
things you can do to try to improve it. Modem "data throughput" as opposed
to modem "connect rate" should be used as a measure of modem
performance. The combination of noisy line and high data rates may lead to
lower data throughput. This is because noisy line conditions may cause
"lost or corrupted" data, requiring re-transmission. If the
modem is transmitting data at a higher rate than the line can accommodate, the
rate of re-transmissions will be higher, leading to lower throughput since the
same information might be sent multiple times.
One strategy for improving modem performance is monitor data throughput
(while controlling the modem connect rate), and choosing a receive buffer
setting (see below) that yields the highest throughput.
The basic steps to perform this optimization is as follows:
1) Setup "Performance Monitor" to show RAS Throughput.
Click "Start", then select "Run.."
Type "perfmon" in the Run dialog box.
Right-Click on grey display window, then select "Add
Counters..."
The "Add Counters..." window will open. Make your selections
to appear like the following:
After clicking "Add", then "Close", the Performance
Monitor screen will appear like this:
2) Make a connection to your ISP. While browsing the web and downloading
files, make note of "Last" and "Average" throughput during
your session.
3) Hang up your modem after you get a general picture of your current
throughput.
4) From the Control Panel, double-click "System", then click the
"Hardware" button. The "Device Manager" will open up. Click
on the "+" to the right of "Modem". Double-click on the
modem that is listed. Click on the "Advanced" tab, and adjust the
"Receive Buffer" setting. Click "OK" until you are
back to the "Device Manager".
5) Repeat step 2 and observe any improvement or degradation in modem
throughput.
6) Repeat steps 2-5 until you have settled upon settings which yield the
highest throughput.
V.92 is an improvement on V.90 in that it can speed up your Internet experience by
reducing the time required to connect to your Internet server and by increasing
the effective bandwidth of your Internet connection by using V.44 to compress
web-based data.
The V.92 specification designed in increase the quality of your Internet
experience, consists of these new features:
Modem On Hold
Quick Connect
V.44 Compression
Modem On Hold allows you to receive an incoming telephone call while you are
connected to the Internet on the same phone line. Call waiting service from your
phone company and V.92 support from your ISP are required.
Quick Connect feature is designed to reduce the time it takes for your
computer to connect to the Internet. With Quick Connect, the modem identifies
the phone line characteristics during a data connection, saves this information,
and uses the data to compare line quality variables when making a future
connection to the same server. Quick Connect assumes that you will not be
changing ISP numbers or changing phone lines on every subsequent Internet
connection.
Quick connect works while you are on the road, provided you configure the
modem to use the correct regional settings for your
location. The modem must support operation in your present location. Once
the correct regional settings are made, the first connection to the Internet
will be a "normal" connection whereby the modem will determine the
current phone line's characteristics. This information will be used on
subsequent connections to reduce the connection time. If you make Internet
connection using different phone lines each time, you will not benefit from
Quick Connect.
V.44 is a new compression standard designed for use with text-based HTML
files. The most significant improvement will be seen when browsing and searching
the web.
When you attempt to check your modem using the More Info button,
HyperTerminal, or to configure a Dial-Up Networking connection, Windows may
issue a COM Port open error message. This means that some previously installed
modem configurations using the same COM port as this modem are interfering with
its operation. These are most likely old Dial-Up Networking connections. This
problem is corrected by performing the following steps.
Configuring your Modem for Windows XP
/Media
Center Dial-Up Networking
Click Start
Click Control Panels
Click Printer and Other Hardware
Click Phone and Modem Options
Click The Dial up connection you want to change
Click The Modems Tab
Remove all other modes except for the currently installed
modem
Follow the prompts with the information from you dial up
ISP
Configuring your Modem for Windows 2000 Dial-Up Networking
Click Start
Click Settings
Click Network and Internet Connections
Click The Dial Connection that you want to re configure
Click Properties
Make sure your current Modem is checked off
Follow the prompts with the information from you dial up
ISP
Be sure to perform this procedure on all Dial-Up Connections present. After
you have clicked the OK button in the Properties dialog box, restart the
computer. This should clear the Open COM Port error.
If for any reason you are unable to resolve issues with your modem, it may be
necessary to uninstall the modem then reinstall the modem. Uninstall the modem
by performing the following steps.
Double-click My Computer on the Windows desktop.
In My Computer, double-click the Control Panel folder icon.
In Control Panel, double-click the Add/Remove Programs folder icon.
Highlight Conexant Dxxx MDC V.92 Modem and click change/remove.
The system will remove the modem and associated drivers.
