[comp.dcom.modems] GVC 9600 V.32/V.42bis/MNP5 - good or bad modem?

bill@twg.bc.ca (Bill Irwin) (05/17/91)

We're about to buy one of these for evaluation and I was
wondering if anyone has had any experience with them.  The price
of about CDN$500 seems very reasonable for a modem with these
features, but if it is a troublesome modem it is expensive even
if it is free.

Any experiences?
-- 
Bill Irwin    -       The Westrheim Group     -    Vancouver, BC, Canada
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
uunet!van-bc!twg!bill     (604) 431-9600 (voice) |     Your Computer  
bill@twg.bc.ca            (604) 430-4329 (fax)   |    Systems Partner

smartin@Canada.lsil.com (Stephen Martin) (05/22/91)

I have a gvc 2400 baud modem with class 5 MNP, it works ok but you can't turn
off MNP classes 1-4, and i can't get it to do uucp.
--
Stephen Martin               -------    LSI Logic Corporation of Canada, Inc.
Phone: (416) 620-7400     LSI|LOGIC|    Suite 1110, 401 The West Mall,        
Fax:   (416) 620-5005        |     |    Etobicoke, Ontario, Canada.
Email: smartin@lsican.uucp   -------    M9C 5J5
 or    smartin@Canada.lsil.com

root@zswamp.uucp (Geoffrey Welsh) (05/23/91)

In a letter to All, Bill Irwin (bill@twg.bc.ca ) wrote:

 >We're about to buy one of these for evaluation and I was
 >wondering if anyone has had any experience with them.  The 
 >price of about CDN$500 seems very reasonable for a modem with 
 >these features, but if it is a troublesome modem it is expensive 
 >even if it is free.

   I had a pair of these for about a week of evaluation, but the models I had 
were V.32/V.42 (no V.42bis data compression nor V.32bis 14.4 kbps).

   They were no more difficult to configure than USR's high-speed Couriers 
(though I had a head start with them because I'd already wrestled with them 
before and knew what the docs *really* meant whenever they said something 
cryptic or seemingly pointless), and certainly far easier than a TrailBlazer.

   Then again, you're less likely to find many people who claim to have the 
proper configuration and Dialers entry for the GVC.

   Bottom line: they did what they claimed to be able to do, though it took 
me a while to figure out how to make them do it.  Their features aren't 
exactly state of the art, either.  Nonetheless, they seem decently priced for 
what they've got and I don't think you're any worse off with the GVC Super 
Modem 9600 than you'd be with any other modem which offered the same 
features.
 

--  
Geoffrey Welsh - Operator, Izot's Swamp BBS (FidoNet 1:221/171)
root@zswamp.uucp or ..uunet!watmath!xenitec!zswamp!root
602-66 Mooregate Crescent, Kitchener, ON, N2M 5E6 Canada (519)741-9553
"He who claims to know everything can't possibly know much" -me

kherron@ms.uky.edu (Kenneth Herron) (05/24/91)

root@zswamp.uucp (Geoffrey Welsh) writes:

>In a letter to All, Bill Irwin (bill@twg.bc.ca ) wrote:

> >We're about to buy one of these for evaluation and I was
> >wondering if anyone has had any experience with them.  The 
> >price of about CDN$500 seems very reasonable for a modem with 
> >these features, but if it is a troublesome modem it is expensive 
> >even if it is free.

>   I had a pair of these for about a week of evaluation, but the models I had 
>were V.32/V.42 (no V.42bis data compression nor V.32bis 14.4 kbps).

I have one RIGHT NOW for evaluation.  I've discovered a few problems:

1) The \T idle timeout loads improperly from the saved profile when the
   modem is reset.  The value used is 1/2 of the saved value.  No biggie.
   Technical support didn't know about it until I told them.

2) It sometimes, inconsistently, non-repeatably, won't connect when calling
   in to a 1200 baud modem.

3) When dialing into a T2500, I sometimes got V.42bis, 9600 baud, trellis
   coding, and sometimes got V.42bis, 2400 baud, and no trellis.  Again,
   this was non-repeatable and inconsistent.  The GVC tech calling my
   T2500 and the GVC always got 9600/trellis coding.

   By disabling trellis coding in the GVC, I got 9600 and V.42bis every
   time (but I didn't try too many times).

I've also found the modem to be rather poor.  There's no index or table
of contents, and typos abound, including things like "&T" where they 
meant "%T" in a command description.  This is nothing an experienced
manual spelunker can't get by, though.

So, it works but the firmware needs a few more bugs shaken out of it.
The tech indicated they could issue an eeprom upgrade to fix \T, so
if/when they isolate the other problems they should be fixable too.
-- 
Kenneth Herron                                            kherron@ms.uky.edu
University of Kentucky                                       +1 606 257 2975
Department of Mathematics       "So this won't be a total loss, can you make
         it so guys get to throw their mothers-in-law in?"  "Sure, why not?"

bill@camco.Celestial.COM (Bill Campbell) (05/24/91)

In <SMARTIN.91May21214349@torsys02_1.uucp> smartin@Canada.lsil.com (Stephen Martin) writes:

>I have a gvc 2400 baud modem with class 5 MNP, it works ok but you can't turn
>off MNP classes 1-4, and i can't get it to do uucp.

I haven't used this particular GVC modem, but I had some bad
experiences with their 2400 baud modems a couple of years ago.

The problem was that they would overheat and go off into
never-never land.  As I remember, these units had a solid case
with no ventilation holes at all.
-- 
INTERNET:  bill@Celestial.COM   Bill Campbell; Celestial Software
UUCP:   ...!thebes!camco!bill   6641 East Mercer Way
             uunet!camco!bill   Mercer Island, WA 98040; (206) 947-5591

bad@flatlin.ka.sub.org (Christoph Badura) (05/26/91)

In <1991May23.220220.27973@ms.uky.edu> kherron@ms.uky.edu (Kenneth Herron) writes:

I have 2 SM96Vbis+ for evaluation here and am experiencing similar
problems.

>1) The \T idle timeout loads improperly from the saved profile when the
>   modem is reset.  The value used is 1/2 of the saved value.  No biggie.

Mine will double the value of the \T register at random after reset. :-)

>3) When dialing into a T2500, I sometimes got V.42bis, 9600 baud, trellis
>   coding, and sometimes got V.42bis, 2400 baud, and no trellis.  Again,
>   this was non-repeatable and inconsistent.

Mine weren't able to hold a V.32, trellis coding connection to several
T2500s and one Fury 9600TI (a german made modem which is said to hold
a V.32 connection even over rather noisy lines) for longer than a
minute (sometime less then 20 seconds on a local call).

>   By disabling trellis coding in the GVC, I got 9600 and V.42bis every
>   time (but I didn't try too many times).

I've been using this setting with the same result for 2 days. Seems to
work reliable.

At the moment I have the problem that that the stupid thingie insists
on loading \H1 even though I have set \H0 in both profiles thus
getting HP ENQ/ACK flow control. Anyone seen this problem?

I noticed also that the S23 register doesn't reflect the Baudrate and
Parity correctly. I tried 9600 and 19200 with no parity.

If I could get them to load the profile correctly i would be quite
pleased with them.

For what it's worth, ATI1 yields "173" and "V2.5" and ATI4 gives "SM96V+
V.42BIS" and "C-CODE".

>I've also found the modem [manual to be rather poor. There's no index or table
>of contents, and typos abound, including things like "&T" where they 
>meant "%T" in a command description.  This is nothing an experienced
>manual spelunker can't get by, though.

My manuals do have an index and a table of contents, but the V.42bis
supplement is somewhat contradictionary to the normal manual.  I
wouldn't compare the handbook with the one for my T2500 but it isn't
really bad.

	chris
-- 
Christoph Badura					Karlsruhe, Deutschland
bad@flatlin.ka.sub.org					+49 721 606137