I have a 3Com USR internal 56K Voice/Fax modem which I purchased at Frys
Electronics in May of '99 for $150. It has performed very well with good
through-put since then with my Allvantage ISP up until about six months ago,
whereupon the connect speed gradually began to degrade from the always
obtainable 50.666kbs down to the point where now I rarely get a 50.666kbs
connection and when I do the through-put rate I get on the PCPitStop.com
download bandwidth test is often below 10kbs, and typically around 5kbs.
However, at the same site their upload BW test gives me very much higher
numbers >40kbs. This could be a clue as to what is wrong with my modem with
the SLOW DL numbers.

I borrowed a Toshiba 8000 Techra and tried it on my same phone line and same
phone number and it always connected at 52kbs and showed 42kbs through-put
on the same PCPitStop DL BW test. Based on this and the line connect diagnostics
shown below, would you agree that the problem is not in the phone line or server?

Since nothing has changed on my Win98 PC I suspect that possible upgrades to
the phone line and/or server have rendered the 1998 V.90 coding in my modem
controller obsolete. I have the 00568500ud.exe controller code update file from
the USR ftp update file server site on my HD ready to go, but I am afraid to run
it until I get some advice from this forum as to whether this is the wise thing to
do and some specific instructions on how to run the update.

Any assistance or advice given here will be greatly appreciated.

Thanks

Ollie Angell

Line connect diagnostics pasted from Hyperterm:

at
OK
ATI4I6I7I11Y11
U.S. Robotics 56K Voice INT Settings...

B0 E1 F1 L2 M1 Q0 V1 X4 Y0
BAUD=115200 PARITY=N WORDLEN=8
DIAL=TONE ON HOOK CID=0

&A3 &B1 &C1 &D2 &G0 &H1 &I0 &K1
&M4 &N0 &P0 &R2 &S0 &T5 &U0 &Y1

S00=000 S01=000 S02=043 S03=013 S04=010 S05=008 S06=002
S07=060 S08=002 S09=006 S10=014 S11=070 S12=050 S13=000
S15=000 S16=000 S18=000 S19=000 S21=010 S22=017 S23=019
S25=005 S27=000 S28=008 S29=020 S30=000 S31=128 S32=002
S33=000 S34=000 S35=000 S36=014 S38=000 S39=000 S40=001
S41=000 S42=000

LAST DIALED #: T4751305

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

Chars sent 361329 Chars Received 914871
Chars lost 0
Octets sent 195081 Octets Received 891878
Blocks sent 4123 Blocks Received 7343
Blocks resent 40

Retrains Requested 0 Retrains Granted 0
Line Reversals 0 Blers 612
Link Timeouts 2 Link Naks 8

Data Compression V42BIS 2048/32
Equalization Long
Fallback Enabled
Protocol LAPM
Speed 49333/26400
V.90 Peak Speed 50666
Last Call 00:11:47

Disconnect Reason is DTR dropped

Configuration Profile...

Product type US/Canada Internal
Product ID: 00568500
Options V32bis,V.34+,x2,V.90
Fax Options Class 1/Class 2.0
Line Options Caller ID, Distinctive Ring
Voice Options Speakerphone, TAD
Clock Freq 92.0Mhz
EPROM 256k
RAM 32k

FLASH date 2/24/98
FLASH rev 4.9.1

DSP date 2/24/98
DSP rev 4.9.1

U.S. Robotics 56K Voice 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) 2/6
Recv/Xmit Level (-dBm) 15/10
Near Echo Loss (dB) 7
Far Echo Loss (dB) 0
Carrier Offset (Hz) NONE
Round Trip Delay (msec) 7
Timing Offset (ppm) 1342
SNR (dB) 48.3
Speed Shifts Up/Down 11/5
Status : uu,5,12N,12.1,-15,0N,0,44.6,18.0

Freq Level (dB)

150 25
300 23
450 23
600 23
750 23
900 23
1050 23
1200 23
1350 23
1500 24
1650 24
1800 24
1950 24
2100 25
2250 25
2400 26
2550 26
2700 26
2850 26
3000 26
3150 27
3300 27
3450 28
3600 31
3750 36
OK

Your USR modem reports connect speed of 49.3k which is very good and a peak speed of 50.6k in the diag you posted -
56k modems will up and downshift rates depending upon line conditions.

A modem that connects at 52kbps and gives 42kbps throughput is a perfect example - the 52kbps connect speed is a "lie".

Also see
www.modemsite.com/56k/x2-thru.asp

A throughput test like that at PCPitstop is not the best indication of connection quality either.

Aloha! Richard.