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bad lines and garbage on the line

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KenMeans

Vendor
Mar 6, 2003
3,357
US
I have been using modems for 25 years and in the last few months i have been having more and more trouble with the connections. has anyone else seen this or is it just me ?
 
can you give us some particulars as to what you are Dialing into, what kind of Modem, If anything has happened to your phone line ?
 
the modems i dial into are us robotics of all types but only at 9600 baud. It just seem as if the telco lines have gone down the tubes. We just seem to have more trouble with line noise than we use to.
 
See you mention US Robotics modems. I have a couple of clients using v92 US robotics modems and they seem to be easily affected by noise. Were you able to find if the problem with due to an overly sensitive modem?? Is there a fix??
 
I am stll having trouble but the one thing that made it better was to reload my P.C. and used the drivers that were 3 or 4 years old not the new ones

Ken Means

 
Disconnections may be caused by momentary drops of DTR(Data Terminal Ready). line noice induces DTR if it is a US robotics modem that you use the best solution i can suggest is the init, S25=200.. This sets the duration, in hundredths of a second, that DTR must be dropped so that the modem doesn't interpret a random glitch as a DTR loss. Lowering the port speed to a 57.6 can help as well with DTR.
 
Not a very scientific method of checking, but have you tried plugging a telephone handset into the line(s) used by your modems, and listening for any noise, interference etc?

What about checking the plugs, sockets and cables used between modems and your outside phone line connection. Line plugs and sockets can get dirty and corroded over time, and this can cause the sort of problems you're experiencing. Has Mrs.Mopp run over the cable with the vacuum, and damaged it?

If you're not plugging the modem cable directly into the master socket, i.e. you've got extension wiring etc., try temporarily moving one computer so you can plug it in without any extra cabling. Does this improve things?


ROGER - G0AOZ.
 
Yes I have checked the lines and they are clean. I think the whole problem is the IP long-distance that all of the phone companies are using.

And then if the company that you are calling has an IP PBX it is getting compressed and uncompressed again when it gets to their site thus causing garbage on the line.

Ken Means

 
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