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If
you have a properly installed the modem .inf file,
you normally don't need any initialization
string or extra settings when using DUNS
(dial-up-networking) - the .inf file determines the
init string which - when everything works right -
gives you the best connection possible. But, it
doesn't always work that way, and sometimes you can
improve your connection by adding extra settings
(additional initialization string). Many command
formats are specific to different modem chipsets.
Below the screenshot showing where you go to add
extra settings are some 56k/V.34-related commands
for various modem chipsets. These commands can be
used to enable or disable 56k (V.90, x2, K56Flex,
or no-56k- V.34), error correction and compression
protocols (V.42/MNP).
In
some cases (especially if your connection is
unstable or nearly useless), disabling 56k
on your modem - forcing a V.34 connect - will
result in improved connectivity and
throughput.
The
following screen shoots will show you where to got
to enter these extra settings. Some of these
settings I have test and some of them I haven't. If
your modem won't function after trying these,
delete the extra setting and reboot. Your modem
should then function as before. Then you can try a
different setting. If you are wondering why all of
the commands below are for disable instead of
enable, there is a good reason for this . Modems by
default will always try to negotiate the best
connection they can. So they turn everything on and
go for it. Unfortunately this sometimes cause
problems. Therefore disabling certain protocals can
in fact increase your connect speed or at least
allow you to connect consistantly.

Take special care when giving your modem extra
commands. If the commands are not for the exact
chipset you have they may or may not work. If they
don't work, your modem will probably not respond
properly to your system. If this happens, you will
have to go remove the commands and restart your
system. Then try different ones until you find one
that works.
In most cases if you are connecting slowly like
24,000 bps then disabling Kflex or x2 will speed
things up. If you can't connect at all, then
slowing the modem down by disabling v.90 &
kflex or x2 might help.
Enter in the extra settings box what follows the ~
symbol. Don't enter the ~ symbol itself. I will add
to these when get them. If you find something that
works or have info about other chipsets let me
know. I'll make sure they get posted here.
Tcraig
Sportster/USR
Disable x2 ~ S32=34
Disable v.42 ~ S15=128
Disable V.90 ~ S32=66
Disable V.90 & x2 ~S32=98
Courier
Disable x2 ~S58=1
Disable v.42 ~S27=32
Disable V.90 ~S58=32
Disable V.90 & x2 ~ S58=33
Cirrus MD56xx
Disable x2 ~ +MS=V90,0
Disable v.42 ~+ES=4, 4, 6 %C1
Disable V.90 ~+MS=X2,0
Disable V.90 & x2 ~+MS=V34,1,0,33600
ESS / Teledrive
Disable x2 ~ +MS=17,0
Disable v.42 ~\N5
Disable V.90 ~ +MS=12,0
Disable V.90 & x2 ~+MS=12,0
Rockwell Dual
Disable KFlex +MS=12
Disable V90 +MS=56
Disable V90&Flex +MS=11
Disable v.42 &Q6
Rockwell HCF & Soft56
Disable KFlex +MS=V90,0
Disable V90 +MS=K56,0
Disable V90&Flex +MS=V34
Disable v.42 +ES=1,0,1;
If the above commands seem to lock the modem try
them with AT in front of the above:
Example.. AT+MS=V34
Lucent (Zoom Fax modems)
Disable KFlex s38=0
Disable V90 s109=0
Disable V90&Flex s38=0s109=0
I found that my Usb 56k Zoom modem had faster
through put by disabling the flex protocal. I
logged on slower but everything was much
faster.
Lucent LT
Disable KFlex s38=0
Disable V90 -v90=0
Disable V90&Flex s38=0-v90=0
Disable v.42 \n2
Lucent Venus
Disable KFlex ~s109=2
Disable V90 ~s109=0
Disable V90&Flex ~s38=0
Disable v.42 ~\n2
PCTel HSP
Disable KFlex~ n0s37=14
Disable V90 ~n0s37=13
Disable V90&Flex ~n0s37=12
Disable v.42 ~*
A * means I don't know.
Motorola SM56
Disable KFlex~ *MM15
Disable V90 ~*MM13
Disable V90&Flex ~ *MM12
Disable v.42 ~
The following is a list of computers and extra
settings that helped them to connect more
reliably.
Compaq Presario 4910 56k-DF
s38=v34
HP Pavilion 6630 Conexant Soft56k
PCI s38=0-v90=0
HP Pavilion 6640c Conexant Soft56k
PCI s38=0-v90=0
The above listed machines taken to a different
house would logon at 48k but in the owners houses
they could'nt even logon. With these settings they
reliable logged on at 26.4 or28.8k.....not great
but it works. If you question why this is read the
following from C/Net.
If you have any other codes that I don't have
listed here let me know and I will post them.
The
following is a post from C/Net that describes 56k
access and what it means.
For all the buzz about how 56k will change your
life, a lot can go wrong. Even the technology's
name is little more than wishful thinking: you
won't achieve 56 kbps, even under the best
conditions, for technological and bureaucratic
reasons. To help you understand why, we've
assembled a list of all the potential barriers
between you and that magic number. To understand
some of these roadblocks, however, you need a
handle on how 56k technology actually works.
Roadblocks on the way to 56k All 56k specifications
used today take advantage of nuances in the way the
phone system is designed. In a standard call
between two modems, your data must be translated
into analog "tones" before it can be transmitted
acrossthe telephone network. This translation is
called the digital-to-analog conversion. Once your
data reaches a telephone company's central office,
it's translated back to digital form by a
coder/decoder (codec) for transmission across the
phone company's digital backbone. Unfortunately,
because the telephone network contains some random
noise, the analog-to-digital conversion is only an
approximation of the original digital signal. To
ensure that data remains readable despite the
effects of this quantization noise, transmission
rates are currently limited to about 53 kbps.
However, because most ISPs connect directly to the
phone company's digital backbone using routers,
data coming from an ISP never need undergo an
analog-to-digital conversion. Instead, the data can
be encoded using pulse code modulation (PCM) so
that it remains entirely digital until it gets to
the central office. Once it arrives, the data is
put through a digital-to-analog conversion before
being sent across the analog phone lines to your
modem. And because digital-to-analog conversions
aren't affected by quantization noise, the
result--in theory, at least--is throughput as high
as 56 kbps from the ISP to you. The bad news?
Anything that adds noise to the telephone line or
causes an analog-to-digital conversion between your
ISP and your modem lessens the transmission's
performance. Worse than that, if there's nasty
noise on the phone line, your only solution may be
to move. Scream all you want, but the telephone
company is obligated to provide you with a clean
enough line to get 4,800-bps data rates only. But
those aren't the sum of your potential
troubles.
The FCC says, "No more than 53 kbps!" Although your
modem says "56k," you won't get throughput that
fast, thanks to a speed limit set by the Federal
Communications Commission (FCC). The reason for
that regulation? Sending a signal down a telephone
wire requires electrical power. But the more power
you apply, the greater the chance of a problem
called crosstalk. You've encountered this annoyance
if you've ever heard other people's conversation
during a phone call. To help prevent crosstalk, the
FCC limits the amount of power that phone companies
can use to send signals over the network. And this
cap on signal strength limits data throughput to a
maximum of 53 kbps, regardless of what your modem
can actually deliver. The FCC is currently
reviewing this ruling and may overturn it later
this year to enable true 56-kbps modem
connections.
Office PBX systems If you have to dial 9 to get an
outside line, your office uses a digital PBX
telephone system, which means you also won't be
able to achieve 56k rates. A PBX system
incorporates a codec that performs an
analog-to-digital conversion so that your calls can
be stored digitally on magnetic media, such as hard
disks. This system gives you some great features,
such as employee extensions and call forwarding,
but it also limits your 56k calls to a maximum
throughput of about 35 kbps.
Noisy analog lines Digital lines usually don't
suffer from noise problems, but the analog wires
between the phone company's central office and your
home are a different story. If you hear buzzing or
static when you listen through your phone's
headset, chances are you won't be able to achieve
optimum modem speed. Caller ID, answering machines,
and cordless phones can add even more noise to your
line. To minimize the hum, try disconnecting these
types of devices one by one and listening again to
determine which, if any, are the source of the
problem. If this doesn't work, your line noise may
be caused by nearby power lines or other
environmental or structural factors. In that case,
call the phone company and complain (good luck). In
our testing, we injected white noise called
intermodulation distortion, which is similar to
what you might encounter over analog lines
Central office switch-ups Connections between local
central-office switches can sometimes be a problem.
Old equipment may require analog termination,
resulting in an analog-to-digital conversion as the
call goes through to the next switch. If a local
call to your ISP gets routed through these
"partially analog" switches, you'll lose 56k
capability. If that happens, the telephone company
may be able to tell you which type of switches your
call gets routed through on the way to your ISP.
(One such problem switch is the AT&T 1AESS.
However, the AT&T 5ESS and the Northern Telecom
DMS-100/500 switches should both work fine.)
When you make a long distance call, you can be sure
it's traveling through digital switches only. The
long distance network in the United States is,
thankfully, a fully digital system.
Transcontinental calls, however, use digital ADPCM
encoding for voice compression, which doesn't work
with 56k PCM encoding. You won't be able to get the
higher throughput rates when calling another
continent.
Trouble in the office-to-home commute A number of
problems can occur as data makes its way from the
local central office to your home. Older telephone
lines connect directly to the switch at the central
office, and newer lines go through a digital loop
carrier (DLC). These devices can combine 96
separate lines into one before they reach the
central-office switch. By using DLC, the telephone
company doesn't have to bury as much expensive
copper wire, which saves money and increases
connection reliability. But DLCs can wreak havoc
with 56k. If the DLC is digitally connected to the
switch, no problem--but if it uses a universal
connection, an analog-to-digital conversion will
occur, rendering your modem's 56-kbps capabilities
useless.
There may also be a pad between you and the central
office. A pad balances the volume on both ends of
the line when you make a call. If the pad occurs
before the signal is converted to analog, you'll
see only a slight degradation in 56k performance.
But if you encounter an analog pad between the
central office and your home, up crops another
analog-to-digital conversion to sabotage your 56k
connection. In our tests, we introduced digital pad
impairments to see how each 56-kbps modem handled
them; for the most part, the products did not find
them too bothersome.
Some local lines also run through an amplifier
called a load coil to boost the signal rates across
longer distances. Load coils cause some signal
distortion and will detrimentally affect your
modem's 56k throughput potential. During testing,
we also tested a long local loop containing a load
coil. Many of the products fell back to 28-kbps
rates, while others handled this impairment without
great performance loss.
Connect for success Your ISP must have a fully
digital connection to the telephone company's
central office for 56k technology to work. This
means that the ISP must have either ISDN or a T1 or
T3 line. ISDN is guaranteed to be digitally
terminated, but T1 lines can be broken out into 24
separate analog lines. This setup requires an
analog-to-digital conversion at the ISP's end and
will prevent you from getting 56k speeds.
In the case of 56k technology, ISDN has another
advantage over T1. ISDN generally uses out-of-band
signaling, in which a separate channel is used to
synchronize the flow of data and set up the call,
thereby freeing the line's entire bandwidth for
sending data. T1 lines use what is known as
robbed-bit signaling. In that method, a bit of the
incoming data is stripped off to indicate the
status of an incoming or outgoing call and to
synchronize the data flow, slightly reducing your
maximum throughput.
For more help go to
http://modemhelp.net/ or
http://modemhelp.org/
This modem page is for
information purposes only. Local Line, Inc. Oxford, In. cannot
guarantee that these methods will always prove
effective and is not reponsible for any data loss and/or equipment
damage that may occur. If you have additional questions about using
your computer on the internet, please e-mail us at: tech@localline.com.
Or call us during normal Tech Support Hours Monday through Saturday.
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