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Tl Posts:

Posted - 4/19/2001 10:23:42 PM  Show Profile  Email Poster  Edit Message
I have recently began to experience a VERY frustrating problem. I can't download anything . Web pages and stuff like movies and mp3's are ok, but anything that requires data integrity is a no-go. Zips, exe's, etcetera always have CRC errors. Here's the steps I've taken:

1. Found out a neighbor up the street has the exact same problem on same ISP.
2. We both have same problem on different ISP.
3. Contacted Southwestern Bell.
4. Southwestern Bell says they can't find anything.
5. Came across this site.
6. Ran the diags on my USR/3com internal PCI (5610 i believe)

I think all my values are in the norm except for my codec distortion figure of 29.3. The site says high 20's are bad. What exactly does 'codec distortion' mean? Will the phone company know what I'm talking about when I say I have a 'codec distortion of 29.3'?

Of course I may have missed some other clues. I'll list my ATI6I11Y11 for anybody to peruse. Any help is MUCH appreciated.

U.S. Robotics 56K FAX INT Link Diagnostics...

Chars sent 51728 Chars Received 305937
Chars lost 0
Octets sent 27776 Octets Received 161025
Blocks sent 1235 Blocks Received 1418
Blocks resent 6

Retrains Requested 0 Retrains Granted 0
Line Reversals 0 Blers 19
Link Timeouts 1 Link Naks 0

Data Compression V42BIS 2048/32
Equalization Long
Fallback Enabled
Protocol LAPM
Speed 50666/26400
V.90 Peak Speed 50666
Last Call 00:07:48

Disconnect Reason is DTR dropped

U.S. Robotics 56K FAX INT Link Diagnostics...

Modulation V.90
Carrier Freq (Hz) None/1920
Symbol Rate 8000/3200
Trellis Code None/64S-4D
Nonlinear Encoding None/ON
Precoding None/ON
Shaping ON/ON
Preemphasis (-dB) 7/4
Recv/Xmit Level (-dBm) 21/13
Near Echo Loss (dB) 5
Far Echo Loss (dB) 0
Carrier Offset (Hz) NONE
Round Trip Delay (msec) 9
Timing Offset (ppm) 12025
SNR (dB) 49.9
Speed Shifts Up/Down 0/0
Status : uu,5,12N,12.2,-15,1N,0,52.0,25.9

Freq Level (dB)

150 24
300 23
450 23
600 23
750 23
900 23
1050 23
1200 23
1350 23
1500 23
1650 23
1800 23
1950 23
2100 24
2250 24
2400 24
2550 24
2700 24
2850 25
3000 25
3150 25
3300 26
3450 27
3600 29
3750 33

Tl Posts:

Posted - 4/19/2001 10:29:27 PM  Show Profile  Email Poster  Edit Message
Oops...that listing only shows a codec distortion of 25.9, but the previous connection it was 29.3.
Tl Posts:

Posted - 4/24/2001 9:05:28 AM  Show Profile  Email Poster  Edit Message  v.Richards Homepage
Codec is the device that changes the digital telco network signal to analog; codec distortion would be a measurement of the difference between the expected and actual signal (voltage levels) produced by the codec.

This would not be related to the problem you describe (if I understand what you are describing) - the modem should be using error-correcting protocol (the diags you included so indicate - LAPM from the i6), so if you download a .zip .mp3 or something and it has errors, those errors would come from your ISP or upstream; or, between your PC's bus and the modem.
(Check the FIFO buffer settings for the port);

What is your port speed? You could try lowering your port speed and limit your connect speed to see if problem goes away (which would eliminate anything beyond your ISP).


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