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Connection
Support
- There
is no dial tone. If
you get this error, check to make sure you have the phone line
connected to the correct place on back of your computer. If that is
correct, hook a phone to the wall jack where the computer line is
hooked to and see if you have a dial tone by listening on the phone.
If you have a dial tone, there is something wrong with your modem.
Contact your computer technician. No dial tone with a phone? Call
telephone company.
- Error
691. Your Username or password is invalid. Check to make sure that your username and
password are entered correctly in the dial-in connect window. You
cannot tell what the password is because it is *’s or dots. Windows
XP uses dots and there will be more there than the length of your
password. Windows XP is also VERY bad to lose the password, but it
will still show dots even though it is blank. Click in the
password box and clear it out, then type in your correct password. If
this still does not work, check to make sure you have paid your bill
on time. This is the error you will get if your account gets suspended
for non-payment. Once we receive payment we will reactivate the
service and you will be able to get on.
- Various
other errors that will not let your dial-up connect.
1.
Reboot the computer. You will be surprised at how many problems this
fixes. 2. Check your phone line for noise. If you have a phone hook to
the same line that you dial into the internet on, pick up the receiver
and listen for any kind of humming, popping, hissing, etc… If you
do, it will cause problems. Call the telephone company to come check
your phone lines. 3. You may have a cheap modem. Believe it or not
Compaq, HP, and many other name brand computers have modems in them
that you can buy for $5 to $15 and they just don’t work good here in
the country.
Modems:
Modem Manufacturer Sites
USR - The BEST modem in production
today. Get a hardware modem if at ALL possible. They also make winmodems,
which are the better winmodems out there.
Motorola SM56 - Good Luck! These modems are extremely cost effective
(cheap) and therefore very popular. Line noise causes most of it's
problems. If you live within a few miles of the Telco CO and have a clean
line, they may work.
Lucent Technologies LT Winmodem - Another cheap one here ..oops ... I
mean cost effective :) This one's problem is usually related to
drivers/firmware. Live out in the sticks? Forget it! Give it to Uncle Bob
who lives in the big city :)
to set to v.34 add AT&F-V90=0
Lucent Technologies, 56k Flex AT&F&C1
Lucent Technologies, LT Winmodem 56kflex
AT&D2&C1X4V1Q0S7=70W1\N3&Q5&K3S38=0
Lucent Technologies, LT WinModem AT&FX
Lucent Technologies, LT WinModem 56Kflex AT&F
Lucent Technologies, LT WinModem 56Kflex AT&F1&W^M
Lucent Technologies, LT Winmodem 56Kflex AT&FS=S10
Lucent Technologies, LT Winmodem 56Kflex Enabled S38=1
Lucent Technologies, LT Winmodem 56Kflex Disabled S38=0
Lucent Technologies, LT Winmodem Limit Upstream S37=14
Lucent Technologies, LT Winmodem V.90 Enabled -V90=1
Lucent Technologies, LT Winmodem V.90 Disabled -V90=0
Lucent Technologies, LT Winmodem V.42 enabled
AT&F&C1&D0&K4&Q5&S1\G1-V90=0%C1S6=4S10=25S37=19S38=0
Supra - The SupraMax is a winmodem,
the SupraExpress is a hardware modem. "AT+MS=11" to set the
modem to 33.6
Rockwell
Rockwell based 56k V.90 (flex enabled) +MS=12,1
Rockwell based 56k V.90 (flex and V.34 disabled) +MS=12,1,34667,56000
Rockwell based 56k flex only +MS=56,1
Rockwell based 56k flex, disabled, V.34 only +MS=11,0,9600,33600
Rockwell based 56k flex, disabled, V.34 only +MS=11,1
Rockwell Based 56k V.90 AT&F&W&W1E0X4W2
Rockwell based 56k HCF V.90 +MS=v90
Rockwell based 56k HCF 56kflex +MS=k56flex
Rockwell based 56k HCF 33.6 mode +MS=v34
Rockwell Based 56k HCF V.90 AT&FE0V1S0=0&C1&D2W0
Rockwell Based 56k HCF V.90 AT&FE0V1S0=0&C1&D2W0
WWW.56K.COM's The
Definitive Modem Site. If you can't find it here, it can't be found!
HEAVY DUTY TECH READING: Explains how
our SORRY telephone lines cause poor connections:
Jeff's Introduction to Load Coils and Bridge Taps
The following from Jeff Cartwright
There seems to be some confusion as to what can be causing the new modems
not to reach the Golden ring of 56K baud rates. I may be able to clear
some of this up.. It probably won't help fix the problem but at least we
all point our finger at the same cause and effect.
Load Coils
Load coils (impedance matching transformers) are place along the length of
a long Telco POTs line that exceeds the 6000ft termination spec. The
twisted pair of an analog line is a "balanced pair" interface
with specific impedance terminations 600 or 900 Ohms. The impedance load
are initially found in the Line card of the Telco switch and the telephone
or modem. Impedance load is very different from loop resistance.
Those terminations are engineered for the specific 600 or 900 ohm value to
match the Amplitude and Frequency characteristics of the analog signal.
The proper impedance termination is vital to absorb the maximum possible
power on the line. If the impedance loads are not properly matched to the
signal, they will only absorb part of of the signal and cause an improper
signal transfer to the switches receiver circuitry. The problem starts to
become evident when you wonder this - "If the energy of the signal is
only partially absorbed, what happens to the stuff that's not
absorbed?"
All energy that is not absorbed by the termination load reflects back on
to the copper pair and begins to interfere with the original signal.
Because the reflected signal is usually out of phase from the original
signal, this starts to cause "common mode rejection" or
cancellation or loss of Amplitude at specific "standing wave"
frequencies and their mathematical derivatives. The net effect of that is,
the original signal begins to get crippled by its own reflection.
The Load Coils are placed in the circuit at specific intervals (varies
depending on wire gauge and cable bundling variables) to reduce the
effective capacitance of the extended copper loop and therefore provide a
higher level of predictability across the copper segment. Remember,
impedance matching, in theory, only works if you can predict the signal
characteristics of the waveform being impeded. Anything that drastically
alters the characteristics of the waveform will make the circuit
termination's less effective in absorbing the maximum signal.
The argument is that, three discrete segments of 6,000 feet copper has
less negative capacitive effects than a single copper segment that is
perhaps 18,000 feet long. Therefore, in a long copper loop, Load coils are
placed at strategic points to reduce the negative effects that capacitance
will have on the signal characteristics. Capacitance is the enemy of high
BAUD rate applications. Amplitude can be overcome with amplifiers,
Capacitance is much harder to control cheaply.
This load coil works wonderfully for voice, however the Load coils, with
their purpose to limit excess capacitance, also greatly limits the
frequency spectrum available to the end devices. By the way, Load coils
also help restrict impulse noise or interference from one copper segment
to adjacent copper segment. So in effect may reduce the additional noise
characteristics from loop interference. Now back to the limit of
frequencies.
There are a few variables that affects this discovery either positive or
negative. But in general, placing a Load coil in a Telco voice line
reduces the effective bandwidth by chopping off the top 25 percent of the
available frequencies. If you are to take a tone generator to the lines
you would see the highest quality signal at approximately 1,000 to 2,000
Hz. When the tone generator reached 2900 Hz there would be a significant
"role off" of over 12dB per octave. This reduction explains why
you can't use Load coils in digital circuits. As a matter of reference if
you examined a T1 signal with a scope it would looked like a very phase
distorted 772kHz analog signal. Certainly any facility that limited the
bandwidth to 2900 Hz would seriously choke a signal running at 772kHz. The
same holds true for ISDN BRI which has an effective signal rate of
approximately 40kHz I believe.
So, it becomes obvious that Load coils can cripple the high-speed signal.
Please note, that removing the Load coils will only make the signal worse.
Because of the nature and characteristics of how modems manipulate an
analog signal, removing the Load coils will just cause exponentially more
distortion across the copper segment. If you want to remove the Load coils
you must completely re-engineer the way the data signal is presented to
the copper pair. That's what they did with ISDN. I don't think anybody is
really up for the challenge at this point.
Chapter 2 - Buddah is "on it" about Bridge Taps
These little bastards are perhaps the most annoying and offensive of all
the anomalies found in a Telco copper segment. They are by far the number
one problem you all have getting modems to connect and stay connected at
high speeds. Unfortunately they are riddled throughout most residential
neighborhoods and corporate business parks.
When the phone company runs a cable down the street the cable may extend a
mile or so passed your house. Although no other house or device is using
your specific copper pair, the pair runs out the length of the cable. All
an installer does is take the wires come from your demarc, drag them out
to a junction box or splice box on a poll or pedestal and "Tap"
the wires coming from your house on to a spare copper pair that runs out
the length of the cable. They do not cut the cable pair at the junction
box just incase they have to use the same pair for one of your neighbors
down the road when you move out. Also, in order not to drastically reduce
the amplitude and of the signal coming from your telephone they do not to
terminate the extended cable end either.
That means there may be a one mile cable running from the central office
out past your house and your telephone line is tapped into the middle of
it. It's sort of like having an additional half-mile antenna picking up
all the garbage in the air and feeding it to your telephone equipment.
Assuming for a moment we can deal with the additional idle channel noise
on the copper facility, which even the most unqualified lineman can test
for, (but if you ask him what he's testing for he probably can't tell
you), and tell you some story how your line is the quietest line on the
street, the next hurdle beyond the noise is the reflected signal coming
back off of the half-mile un-terminated antenna they built just for you ay
no additional charge.
When an electrical signal hits the end of a wire it has to go somewhere.
If there is no impedance Load to absorbent the signal, then the signal in
its entirety gets reflected back over the entire copper segment. The
signal that comes from your modem headed for the central office arrives at
a specific time interval and the reflected signal coming back off the
un-terminated copper extension comes then just behind yours causing your
signal to appear phase distorted.
When two out of phase signals all our received at a certain impedance Load
of a cause a rejection affects and begin to cancel each other out. If the
signals arrives 180 degrees out of phase your signal can be canceled out
completely. The more the second reflected signal it is closer to 180
degrees the more the signal will be attenuated and phase distorted. At
lower frequencies problem is not terribly dramatic as these reflections
are only fractions of a waveform out of phase. But when you make the
waveform's smaller as is the case with higher frequencies the problem
becomes exponentially more apparent. Phase is much more and issue with
smaller, shorter or higher frequency waveforms. In a nutshell, we are
screwed.
Even when you can get them to do to customers residence and have a line
tested, DO NOT test the frequency response of the line. They perform two
tests..
the first test it is a 1,000 Hz tone coming from the central office switch
and measured at the customers and demark for attenuation. The 1,000 Hz
tone is significant because it is smack in the middle of the voice
frequency range (your vocal cords cannot really make sound above of 3000
Hz). Assuming they have their test equipment Setup and terminated properly
they can get a dB measurement of the 1000 Hz tone and say that is in some
specified range. Please note that there are no documented specified ranges
for analog voice lines using this test setup. The results of this test are
merely to identify the signal level coming in. I believe somewhere between
-6dbm and -20dbm is acceptable but I'm not really sure.
the second test they may perform it is terminating the line and doing a
Cmsg noise test measuring the title channel noise on the facility with no
signal provided. Ideally there are some specifications that identify how
much of this noise is tolerable for a voice circuit but I'm sure the
tester doesn't know. The tester might as well pickup of the telephone
receiver and below in a to see if the line passes mustard....
The problem was this noise test is that putting a signal on the line
generates additional noise and interference that the modems have to
contend with all the time. This noise is not present when the line is just
quietly terminated at each end.
The test I would really like them to perform is a frequencies sweep
between 300 and 4000 Hz and a Bridge tapped test to determine how out of
phase my signal may look by the time it gets to the central office and
whether it falls into specific characteristics to. If these tests are
routinely performed on the TOLL grade facilities between Telco's central
offices they should also be performed at the customers request on the drop
side of the switched circuit. It time assuming its out of the question.
I've had the conversation with several Telco repair supervisors about
lifting Bridge taps and performing signals-to-noise ratio tests. The
conversation ends when they say " we do not guarantee data of above
2400 Baud". They are right to this is not a conditioned data line and
I have no recourse.
Incidentally, this bridge tap problem became apparent right after 9600
baud modem's war replaced whereas 14.4k a modems. The problem then got
escalated with 28.8 and now begins to take on monstrous effects on the new
super modems.
It is interesting argument, putting these modems on voice lines and
pushing the envelope beyond their engineered usefulness. The real culprits
in this equation is not Telco. It is the bastard scumbag modem
manufacturers pulling the wool over the eyes of the consumer and expecting
us to make it work and/or absorb all of the shit when it doesn't. Telco
does not want you to use high-speed modems on your voice lines anyway so
you'll find a very limited support from that camp.
Damn I have to learn to shut up .. you think .. These get way too long.
Sincerely,
Jeff Cartwright
Network Buddah
Planet Access Networks, Inc.
Stanhope, NJ
201-691-4704
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