Mark Miwurdz

Until I get some kind of wireless broadband set-up sorted out, I'm going to have to make the best of my crappy landline for accessing the internet.

BT did crank up the gain on the line after I ran a Haynes test (AT%Q) but I never get better than 31Kps with a 56K modem.

Is there any kind of device I can use to boost the signal or reduce the noise even further?

Cheers
Kav

Mark Kwiatkowski

Kav,

I can give you some tips on what to check for (some of which you have already done).

Line noise can be caused by several factors. Electro-magnetic interference is often caused by wiring in and around the connection from the modem to the wall jack. It may exist in the phone line being used, or in the jack being connected to. It may be a loose screw on a connector block somewhere between the member and the exchange or water in one of the Telco cable ducts around worn wires. Or it may be anywhere in the wiring within the house. The age of the building and its wiring plays a major factor.

Static will get read as data and cause packets to be lost and resent. At best, it limits the connection speed to something like 26,400. At worst, it will not allow you to connect at all. Generally, though, it is something in between and can be very frustrating.


How to Test for Line Noise

Errors to Expect
The following DUN errors can all be symptoms of line noise or trunking issues.
Error 645: Internal Authentication Error
Error 678: No Answer
Error 679: No Carrier
Error 691: Authentication Failure
Error 718: PPP Timeout
Error 731: Protocol Not Configured
Instant disconnect
Disconnect at variable times

Each of these errors could be something else and should be checked first. The thing we're looking for is inconsistency. If you are getting a 691 every time, it's most likely a mistyped user ID or password. If you get a 691, a 679, then a 731, then connect and get dropped, it's possibly a line noise issue, but this could also indicate bad or out-of-date v.90 firmware/drivers.

Check Line Quality
Listening to a phone line can give you an idea of the noise in the line. In order for you to hear the line clarity, you need to get rid of the dial tone. Plug a handset into the jack, lift it off-hook and press 1. This will give you about 30 seconds of silence to listen for noise. However, this will not always be helpful.

If you are able to connect, but cannot connect at the speeds you expect with the protocols installed, line noise is often the problem. If you get a connection speeds greater than 33.6 and less than 50K, like around 40K, you should check for line noise.

There are tests that can be taken over the internet and by calling into test facilities of many modem manufacturers. USR's Line Test at http://www.3com.com/56k/need4_56k/linetest.html is the best known. However, this will not give you an indication of the line quality between your home and the location of your ISP's Point of Presence (POP). By following this test you can get an idea of whether the quality of the phone line, between your home and your ISP's POP, is conducive to making a high speed connection to your ISP. This test will work for many 56k modems. From my personal and professional tech support experiences, when using the 3Com 56k line test, a test result that shows 56k is possible is nearly 85% accurate. On the other hand, a test result that shows 56k is NOT possible is nearly 99% accurate.


Open up Terminal in Windows 3.1x or Hyperterminal in Windows 95/98/ME/NT/2000.
At the terminal window at a cursor prompt, type ATZ and hit the Enter key, even if you don't see anything appear on the screen. It should respond with OK.
Now type ATDT####### (where ####### is your ISP access number) and hit Enter.
The modem should dial and connect to your ISP. You will either see a "Login" or "Password" prompt. If the prompt has mixed signals (i.e. "Log#BJDx_in"), there is noise on the line. If you get nothing but garbled text streaming across the screen, you definitely have a line noise issue.
Type +++ but DO NOT HIT ENTER. The modem should respond OK after a second.
Type AT&E1&V1 and hit Enter. The modem should respond with a list of information related to the connection. Look for a listed as Line Quality and write it down.
For Conexant/Rockwell modems and others, type AT%L%Q.
The Line Level (%L) is in -dBm and should be less than 24.
The Quality Monitor level (%Q) of 15 or higher mean there are real line problems with the member's Telco circuit. They will need to contact the Telco.
For USR modems, type ATI6 and look for "Blers" (Bit Link Error RateS) value. It should be less than 3, ideally 0. Anything higher and the member has a line noise issue.
Type ATH and Enter to disconnect the modem from your ISP.
Repeat steps 3 through 6 AT LEAST 5 TIMES. This will give you an average value for the Line Quality between your home and your ISP.
Line Quality values greater than 25 indicate that the modem is sensing excessive line noise. When this is the case, there is usually not much that can be done to decrease the noise. You may want to contact the phone company to determine whether they may be able to enhance the line quality.


Solutions
Reduce Local Line Noise
By local line noise, I mean the line noise generated by devices and lines the member has setup in conjunction with the modem.
Remove other phones, fax machines, answering machines, caller ID boxes, other computers, line splitters, and surge protectors from the line. Connect the modem directly to the wall jack.
Clear away all other power sources and wires around the phone line and jack.

Try changing the connection wire.

Try connecting to another jack in the building. If practical, try another location.

If you can dial long distance and the problem disappears, the member's equipment is fine.

Modem Settings
There are some modem settings you can adjust to help deal with line noise.

Diable 56k
Set S10=50 or higher (no higher than 254)in Extra Settings. This is the amount of time in tenths of a second that the modem will wait before dropping the carrier if there is some sort of interruption in the data flow on the phone line.

Lower the modem port speed and/or the FIFO buffers.

Enable software compression (works very well on a WinModem).

Enable error control with data compression (some WinModems will have problems with this).

I'm still having problems, who do I talk to now?

After fully testing all of the potential fixes and eliminating a matter as many external factors as possible, either it's a bad/out-of-date modem firmware/driver, a bad line, a trunking issue or even a bad modem. If the issue seems to be a bad POP or a trunking issue, check the network status page for your ISP, usually located on your ISP's help site. If nothing is listed, contact your ISP's technical support department via phone to inform them of the problems you're having. Make sure you kept track of all the troubleshooting you've already done, because you need to make the tech support representive aware of all of your actions. This will allow them to quickly find the issue causing your problem. If the issue is a local line noise issue or a modem problem, you would need to contact your local telephone company for assistance or your modem manufacturer or computer retailer for the modem problem.

Hope this helps.

Mark

[Edited by Mark Kwiatkowski - 9/20/2003 8:54:42 AM]

Mark Miwurdz

Fantastic!

Thanks mate and plenty to go on. I'll let you how it goes.

Cheers
Kav