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From: j...@im4u.UUCP (John Quarterman)
Newsgroups: net.periphs,,net.lan
Subject: 2400 (or higher) baud modems
Message-ID: <632@im4u.UUCP>
Date: Thu, 14-Nov-85 17:59:11 EST
Article-I.D.: im4u.632
Posted: Thu Nov 14 17:59:11 1985
Date-Received: Fri, 15-Nov-85 20:49:01 EST
Organization: U. Texas CS Dept., Austin, Texas
Lines: 45

This is a survey on 2400 baud or faster modems, as subject
which should be of interest to many, considering the increasing
traffic on both the UUCP and USENET networks, and the lessening
ability of a few sites to handle major parts of the load for the rest.

If someone has done such a survey recently, please just tell me.
In any case, please *MAIL*, do NOT post, all responses and I will summarize.
This is especially important since some of the newsgroups
I'm posting to may or may not be appropriate.

Your name and address will be included in the summary unless
you explicitly state otherwise in your response.

What I'm interested in are 2400 baud modems which can be used
to run UUCP or SLIP (TCP/IP over RS232).  Faster modems are also
of interest, though it's not clear we can afford to buy any.
However, they must run over unconditioned telephone lines.
Asynchronous preferred.

Specific information of interest:

What modems you use, and for what (UUCP, USENET, terminal dialup, SLIP, etc.).
What other modems you know of.

For each modem model:
Manufacturor's name, telephone number, and address.
Same for distributor, if different from manufacturor.
Date available, model number, autodial, speeds, synchronous/asynchronous.
Rack mount or other.
Price, and discounts (bulk, academic, other).
What other modems they are compatible with:
since there seem to be at least two different 2400 baud standards,
this is of particular interest.  If someone could send me a brief
summary of the various standards in use, that would be a big help.

Any other comments you'd care to add.

Remember:  MAIL, do NOT post news!  I will summarize.
Your name and address will be in the summary,
unless you explicitly tell me not to put it there.

John Quarterman,   UUCP:  {ihnp4,seismo,harvard,gatech}!ut-sally!im4u!jsq
ARPA Internet and CSNET:  j...@im4u.UTEXAS.EDU, formerly j...@im4u.ARPA

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From: j...@im4u.UUCP (John Quarterman)
Newsgroups: net.periphs,,net.lan
Subject: Re: 2400 (or higher) baud modems (1 of 4)
Message-ID: <667@im4u.UUCP>
Date: Sun, 24-Nov-85 14:52:43 EST
Article-I.D.: im4u.667
Posted: Sun Nov 24 14:52:43 1985
Date-Received: Tue, 3-Dec-85 20:21:55 EST
References: <632@im4u.UUCP>
Reply-To: j...@im4u.UUCP (John Quarterman)
Organization: U. Texas CS Dept., Austin, Texas
Lines: 159
Keywords: 2400 baud, modem

>From: j...@im4u.UUCP (John Quarterman)
>This is a survey on 2400 baud or faster modems, as subject
>which should be of interest to many, considering the increasing
>traffic on both the UUCP and USENET networks, and the lessening
>ability of a few sites to handle major parts of the load for the rest.

This summary was prepared by Carol Kroll, who didn't realize beforehand
what she was getting into.  A couple of disclaimers to add to what she writes:

	The set of newsgroups being posted to here may or may not
	be appropriate.  If not, sorry about that, but remember that
	at least B news only transfers one copy and uses links.

	Some of the responses arrived as inclusions inside responses
	from other people, as they had evidently been responses to
	earlier surveys.  Due to time constraints, we have not been
	able to ask permission to post every such included letter,
	and have assumed that you wanted your letter public.

On to Carol's summary.  -jsq

Our thanks to everyone who replied to this survey.  It turns out that
an information summary on these modems is already available, in an
article by Brian Edwards in the October 1985 issue of Hardcopy
(Vol. 14, No. 10).  It includes an 8 page chart describing the
interface, protocols, jacks, features, and price of over 60 different
manufacturers' 2400 baud modems.  There appear to be a few inaccuracies,
but the list is certainly helpful.  Missing from the Hardcopy list are
the USR Courier 2400,  CTS Datacomm 2424AD, and Electronics Vaults
UPTA-96/S.  Information on them follows.  The CDS 224 is in the
article, but the info Tim Radzykewycz sent is more complete, and is
also appended.

This is the first of four messages.  The others are: (2) a reposting
of a description of 2400 transmission protocol types and standards
by Bob Cunningham of Hawaii Institute of Geophysics from May 85,
(3) a summary of comments people sent about their experience with the 
USR Courier 2400, (4) summary of comments on other types of modems.

Manufacturer	USRobotics    
Distributor	Tek-Aids
		1400-A Smith Rd
		Austin, TX
		(512) 385-0590
Modem		Courier 2400   
Interface	RS232
Price		440.00  
Baud or bps	300/1200/2400     
Protocols	Bell103/Bell212A/CCITT V22.bis
Housing		Standalone
Autodial?	yes
Asynchronous?	yes
Public switched
tele. network?  yes
Warranty	2 years
Other		autobaud in answer mode

Manufacturer	CTS Datacomm
		(203) 743-3681, Pete Coccaro
Distributor	Hall-Mark Electronics
		12211 Technology Blvd
		Austin, TX 78727
		(512) 258-8848
Modem		CTS-2424ADA (CTS-2424AD rackmount)
Interface	RS232
Price		315.00 (495.00)
Baud or bps	300/1200/2400 
Protocols	Bell103/Bell212A/CCITT V22.bis
Housing		Standalone (card)
Autodial?	yes
Asynchronous?	yes
Public switched
tele. network?  yes
Other		autobaud in answer mode
		16-card rack is $795.00
		stores 10 numbers

>From: ut-sally!seismo!gould9!sdcc3!ucbvax!calma!radzy (Tim Radzykewycz)

    manufacturer:	Concord Data Systems
			303 Bear Hill Road
			Waltham, MA  02154
			(617) 890-1394	telex 95-1793
    distributor:	We used:
			Electro-Data Marketing
			552A Valley Way
			Milpitas, CA  95036
			(408) 945-1300
    available:		currently
    model number:	224 Autodial Modem
    autodial:		yes
    speeds:		1200/2400
    synch/asynch:	asynchronous
    housing:		standalone
    price:		$689 on 3/85
    discounts:		unknown
    compatibility:	2400: ccitt v.22bis
			1200: bell 212
		    let me quote the manual here:
			...conforms to the following recommendations:
			o EIA RS232, RS422
			o CCITT V.24, V.28, V.54, V.22bis (at 2400bps)
			o ISO and IEC specifications relevant to data
			  modems and interfaces
			o Bell 212A (1200bps mode only)
    use:	These modems are only used for dial-in.  Right
		now, we are receiving UUCP (from SUN) calls
		and interactive use from home.
	1.	These modems do not have fuses.  We recently had one
		die because of this.  I returned it a week ago, and
		it is not back yet.
	2.	The command set is non-hayes compatible.  This is
		not so good for uucp dial-out, but fine for dial-in.
		There were some requests out a while ago in net.wanted
		for uucp drivers for these beasts, but I didn't grab
		I think the command set is better than Hayes.


    manufacturer:	Electronic Vaults, Inc
			12347-E Sunrise Valley Drive
			Reston, VA  22091
			(703) 620-3900
    distributor:	direct from mfg
    available:		currently
    model number:	UPTA-96/S
    autodial:		yes
    speeds:		4800/7200/9600
    synch/asynch:	asynchronous
    housing:		standalone -- Also available in IBM-PC version.
    price:		$995 on 8/85 ($895 for PC version)
    discounts:		unknown
    compatibility:	none
    use:	We have one set up for dial-in on one of our machines,
		and the other is used from home for dial-in.  We plan
		to test this out for uucp, but haven't done so yet.
	1.	This is a half-duplex modem, and it takes a significant
		amount of time to switch transmission directions.  This
		makes it somewhat poor for interactive use.
	2.	We've had some problems with keeping the lines up.
		Every once in a while, the modem I have at home will
		print the message "OK\nRING\n", and disconnect you.
		Electronic Vaults has sent me new ROMs, but I haven't
		yet installed them.
	3.	They are very reliable, except for the above problem.
		I have *never* gotten a "noise" character with these.

John Quarterman,   UUCP:  {ihnp4,seismo,harvard,gatech}!ut-sally!im4u!jsq
ARPA Internet and CSNET:  j...@im4u.UTEXAS.EDU, formerly j...@im4u.ARPA

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From: j...@im4u.UUCP (John Quarterman)
Newsgroups: net.periphs,,net.lan
Subject: Re: 2400 (or higher) baud modems (2 of 4)
Message-ID: <668@im4u.UUCP>
Date: Sun, 24-Nov-85 15:00:48 EST
Article-I.D.: im4u.668
Posted: Sun Nov 24 15:00:48 1985
Date-Received: Thu, 5-Dec-85 04:23:54 EST
References: <632@im4u.UUCP> <667@im4u.UUCP>
Reply-To: j...@im4u.UUCP (John Quarterman)
Organization: U. Texas CS Dept., Austin, Texas
Lines: 132
Keywords: 2400 baud, modem, CCITT V.22 bis, CCITT V.26 ter
Summary: V.22 bis is sort of standard in the States

The comments in square brackets in the following article were there
when we got it:  they aren't by me or Carol.  Thanks to Bob Cunningham
for the original posting:  hope you don't mind the reposting.  -jsq

>From b...@islenet.UUCP (Robert P. Cunningham) Wed May  8 18:25:37 1985
Path: ukma!cbosgd!ihnp4!mhuxn!mhuxr!ulysses!allegra!mit-eddie!genrad!decvax!ittvax!dcdwest!sdcsvax!noscvax!uhpgvax!islenet!bob
>From: b...@islenet.UUCP (Robert P. Cunningham)
Newsgroups: net.dcom,
Subject: 2400 bps modems can be non-standard
Message-ID: <1097@islenet.UUCP>
Date: 8 May 85 22:25:37 GMT
Distribution: net
Organization: Hawaii Institute of Geophysics
Lines: 112

[These are my notes on some problems with U.S.-made 2400 bps modems,
using information from a variety of different articles and discussions
with various vendors.  Clarifications and corrections welcome.]

2400 bps modems.  Twice the throughput of 1200 bps modems for less than
twice the price.  It sounds good, but many of the new 2400 bps modems
now on the market in the U.S. are not completely compatible with similar
models from other manufacturers.

There is no U.S. asynchronous dial-up 2400 bps standard in the same sense
that the Bell 212 modem set the standard for 1200 asynchronous modems.

There are two European standards: "CCITT V.22 bis" and "CCIT V.26 ter".

These are written standards, while the Bell 212 was a complete
working product, with very well known operating characteristics.  A
minor difference in principle, but a tremendous difference in practice.

Not only are there loopholes in the CCITT standards that give each
manufacturer considerable room to be creatively different, but there are
some modifications that U.S. manufactures tend to make in
order to maintain some compatiblity with existing U.S. equipment.

The result is that many of the 2400 async dial-up modems are
incompatible with each other in various ways.

Most of the new U.S. made 2400 bps async dial-up modems
follow the V.22 bis standard.  They transmit and receive
simultaneously by splitting the available bandwidth in half, using half
to receive and the other to transmit, with a 16 point Quadrature
Amplitude Modulation (QAM) technique at 600 baud [precisely speaking,
the baud rate is the rate of change of the signal ... QAM and most other
techniques provide a way of encoding several bits into each change of
the signal].

A few use an alternate CCITT specification -- V.26 ter.  
Signal cancelling (the receiver cancelling out the echo of its own
transmitted signal) allows the whole bandwith of a phone line to be
used.  V.26 ter uses a Differential Phase Shift Keying technique to
handle 2400 bps at 1200 baud.

V.22 2400 bps is probably less reliable than 212-type 1200 bps over
long-distance lines, V.26 ter is probably better than 212.

Of course V.22 bis and V.26 ter are completely incompatible.

While V.22 bis seems to be the preferred standard now, there is a good
chance it may eventually be superseeded by V.26 ter.  [Then again, maybe not;
the Vadic 1200 bps technique is -- in some ways -- more effective than 212,
but it's never really caught on.]

Now, about those loopholes in V.22 bis ...

The standard designates a fall-back speed, if the originate and answer
modems can't handle a 2400 bps connection.  However, the standard
doesn't specify how the connected DTE equipment (computer or terminal)
is to be notified of the fall-back.  The RS232C standard doesn't cover

With V.22 bis, each U.S. manufacturer seems to have chosen a DIFFERENT
way of indicating a speed change when the modem falls back, using
various of the seldom-used secondary control pins on the RS232C

Chances are that the typical DTE device you hook up your 2400 bps modem
to will ignore the speed change signal.  Then, when you obtain a dial-up
connection that's a bit noisy, the modem falls back.  It sets up and
maintains the connection nicely, but not at the baud rate your computer
or terminal expects.  This can tie up the equipment at each end

V.22 bis specifies the CCITT V.22 format for 1200 bps fallback.
Unfortunately, that's incompatible with Bell 212.  To allow V.22 bis
modems to be used together with regular 212 modems, many (but not all)
of the U.S.  manufacturers have chosen to make 212 rather than V.22
the fallback.

As a convenience, some (but, again not all) of the U.S. makers who
provide 212-type 1200 bps fallback also provide a further 103-type 300
bps fallback from 1200 bps.  Nice feature, but definitely not in V.22 bis.

There's still another common "Americanization" that U.S. manufacturers have
adopted.  V.22 bis assumes that the European standard 2,100 Hz answer
tone be sent by the answering modem during initial connection
handshaking.  Many U.S. manufacturers have instead adopted the regular
U.S. 2,225 Hz answer tone -- again for 212-type compatibility.

Unfortunately, this means that many U.S.-made V.22 bis modems
won't handshake at all with a European V.22 bis modems.

V.22 bis specifies V.25 (or V.25 bis) autodialing.  U.S. makers
prefer their own variation of the Hayes autodialing commands (or the
Concord technique, or the AT&T technique, or Cermatek ... there's
definitely no effective U.S. standard for autodialing commands).

Summary & recommendations:

If you want a 2400 modem that will talk to European-made modems
make sure it uses the 2.1 kHz answering tone, and has V.22 (not 212)
fallback.  Find out whether the other end uses V.22 bis or V.26 ter.

If you need point-to-point 2400 bps dialup in the U.S., choose your
favorite manufacturer, but you'll have more consistent results of you
have the same model from the same company at the other end.  Otherwise,
don't be surprised when your modem "hangs".  In any case, may expect
to see more "phone line hits" -- especially over long-distance lines --
than you get with your 1200 bps modem.

Bob Cunningham   ..{dual,ihnp4,vortex}!islenet!bob
Honolulu, Hawaii

John Quarterman,   UUCP:  {ihnp4,seismo,harvard,gatech}!ut-sally!im4u!jsq
ARPA Internet and CSNET:  j...@im4u.UTEXAS.EDU, formerly j...@im4u.ARPA

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From: j...@im4u.UUCP (John Quarterman)
Newsgroups: net.periphs,,net.lan
Subject: Re: 2400 (or higher) baud modems (3 of 4)
Message-ID: <669@im4u.UUCP>
Date: Sun, 24-Nov-85 15:09:12 EST
Article-I.D.: im4u.669
Posted: Sun Nov 24 15:09:12 1985
Date-Received: Thu, 5-Dec-85 04:24:19 EST
References: <632@im4u.UUCP> <667@im4u.UUCP> <668@im4u.UUCP>
Reply-To: j...@im4u.UUCP (John Quarterman)
Organization: U. Texas CS Dept., Austin, Texas
Lines: 329
Keywords: 2400 baud, modem, USR Courier
Summary: Many have tried the 2400 baud USR Courier 2400, with differing results.

In response to this survey there were many comments on the USR Courier
2400 modem, which are summarized below:

>From ut-sally!seismo!gould9!sdcc3!ucbvax!calma!radzy Sun Nov 17 07:54:54 1985

    manufacturer:	US Robotics
			8100 North McCormick Blvd.
			Skokie, IL  60076
    distributor:	We used:
			Electro-Data Marketing
			552A Valley Way
			Milpitas, CA  95036
			(408) 945-1300
    available:		currently
    model number:	Courier 2400
    autodial:		yes
    speeds:		300/1200/2400
    synch/asynch:	asynchronous
    housing:		standalone
    price:		approx $600 on 3/85
    discounts:		unknown
    compatibility:	I can't find any protocols in the manual,
			however, it talks with the CDS modem (and
			I presume Hayes 2400).
    use:	These modems are used for people to log in
		on.  They are only used for interactive use
		from home.
	1.	Some early models had non-working ROMs in them.
		We got one of these.  The fix is simple.
	2.	We're reasonably happy with these.


Tim (radzy) Radzykewycz, The Incredible Radical Cabbage

>From: W8...@SIMTEL20.ARPA (Keith Petersen)

The following review was not written by me.  It was downloaded from a
Remote CP/M system.  Unfortunately there is no way to reach the author
because it is unsigned.  It is presented here for its possible
informational value.  Please address discussions/comments to the
mailing list, not me.  I don't own a 2400 baud modem.

10 Mar 85



	The USR Courier seems to be the first smart low-priced modem
to be released, probably due to the fact that, unlike many
manufacturers, it does not use the Rockwell chip set.  It features
Hayes 2400 compatibility.  I will briefly summarize the positive
aspects of the modem:

	- externally accessible, well-labeled configuration switches
	- external switch to reverse pins 2 & 3, thus eliminating the
	  need for a null modem
	- result codes can be completely turned off via switch
	- volume control for internal speaker

	After setting the configuration switches (an easy task for
anyone who has ever set up a modem) the Courier is ready for
operation.  With the appropriate switch setting, it can be used both
in originate and answer mode without any hardware changes.

	Originating a call can be accomplished with the now-famous
ATDT sequence, except that command letters no longer have to be in
caps. As with other smart modems, any character typed while dialing or
waiting for carrier aborts the action and hangs up the line.  The
"escape" character can be used to either return the modem to command
mode (like the Hayes) or to hang up (like other USR modems) depending
on a configuration switch setting.

	The Courier was used to successfully connect to the local
TYMNET number.  A later model also was able to talk to a VADIC 2400
baud unit over long distance (Wayne Masters' RCPM).  The Courier was
also able to call and be called by a Penril 2024 and another Courier.

	As to autoanswer mode, the modem was a complete washout to put
it mildly.  Surely, hard- and software are partly to blame but the
fact that other modems (including USR Password and AD212A) work with
the same setup indicates a serious flaw in the Courier.

	The hardware used, for whatever reason, drops DTR while
changing baud rates.  The duration is so short that all other modems
tested on the hardware, EXCEPT the Courier, are totally unaffected.
The Courier will, upon carrier lock and receipt of the first character
typed, drop the carrier 3 out of 4 times at 1200 and 2400 baud.  While
no considerations were given to 300 baud performance, it was noted
that those problems only exist at 1200 and 2400 baud.  Placing a 5MFD
capacitor from the DTR line to ground totally fixed this problem.

	In autoanswer mode, the modems were used as follows:
   - all result codes are inhibited
   - on carrier loss, computer reboots, cycles DTR, then waits for a
     character typed by constantly polling the data input port
   - on receipt of character, baud rate is tested and, if necessary,

	I must again stress that this method works with all modems
tested.  The USR Courier, however, would simply refuse to answer any
more phone calls after answering a few.  No set pattern was
discovered.  Sometimes, the modem would work properly for 5-10 calls
then refuse to answer, at other times it would only allow 1 or 2
calls.  When it refused to answer, no outside indication was given
as to the problem.  The appropriate LEDs on the front panel were lit
yet the modem did not respond to the ring.  Surely, this is a most
serious deficiency and I have decided that the Courier is unfit for
use in this particular application.  I am convinced the problem lies
solely with the Courier, particularly sonce both the Auto Dial 212A
and the Password 1200 work in the exact same environment (except for
the much-needed 2400 capability, of course).

	In closing I must again stress that the USR certainly is a
superb modem and very well suited to originate applications.
Considering that 99 out of 100 modems sold will never be used for pure
autoanswer purposes, the Courier is not at all a failure.

	One modem was tested in late November, two in late February
(both were preproduction units) and thre PRODUCTION units were tested
in March.  All five units exhibited the same problems.

	...may those who have the power to change things do so, may
those whose toes I stepped on test for themselves before stepping on
mine, may those who want to buy a Courier not be discouraged.

	If YOU intend to use a USR Courier in an autoanswer-only
environment, please by all means give it a try, it may sure work for
you.  If it doesn't, you have been warned, and if it does, either
"they" fixed it or the problem is installation-dependent...

>From ut-sally!topaz!packard!cbosgd!rice!neuro1!sob Mon Nov 18 14:17:05 1985

I have sent you all I have, hope it is helpful.

>For each modem model:
>Manufacturor's name, telephone number, and address.
USR ROBOTICS, 8100 North Mc Cormick, Skokie,IL 60076
They have an 800 number, but I don't have it handy.
>Same for distributor, if different from manufacturor.
See enclosed text to follow
>Date available, model number, autodial, speeds, synchronous/asynchronous.
They are currently available, Courier 2400, Hayes command set auto dial,
300 (103), 1200 (212A), 2400 (CCITT V.22bis), asynchronous only
>Rack mount or other.
stand alone only
>Price, and discounts (bulk, academic, other).
We got ours for $399 from a particular distributor that seismo
>What other modems they are compatible with:
They work with the Hayes 2400 and all the 1200's I have do uucp with.
(RIXON R212A, Hayes 1200, Cemetek Info-mate)

Please let me know your thoughts if any about this topic.

>From USENET, by Rick Adams <seismo!rick>:

I have spent the last 2 weeks evaluating a US Robotics Courier 2400 modem.
I have beat on it pretty severely and can't find anything wrong with it.
We are buying several. I like it well enough that I will probably buy
myself one for home use.

The modem was used for uucp traffic on seismo for 2 weeks. It was
used for both dialins and dialing out. The ONLY problem I could find with it
is that if you try and call another site at 2400 baud and it can
only sync up at 1200, the modem prints "CONNECTED 1200" and then resets
the baudrate to the host to 1200 baud. I added 5 lines of code to the
dialer in uucp and have had no problems since. I consider this to be minor.

Anyway, on to details. The GSA cost is $399 quantity 1. If you are not on the
GSA scale (i.e. if you don't buy as a US government agency), you can still
get it at this price by mentioning you heard about this price from The
Center for Seismic Studies (i.e. where I work). The list price on this model
is $895 and the regular non-GSA price is $479 (other dealers may charge more).

The modem operates at 300/1200/2400 baud (Bell 103/Bell212A/CCITT V22.bis)
in both originate and answer mode. It will fall back to 1200 from 2400,
but not from 1200 to 300 in orignate mode and correctly autobaud in
answer mode. A nice (and undocumented feature) is that the modem will
detect what baudrate the computer is sending at and use that as the
dialout speed. This means you can just list the same modem in your
L-devices file 3 times with different speeds and not change anything else.
[it's simpler than it sounds if you are confused]

In orignate mode, it will detect (with a serate message for each)
ringing, busy, dialtone, and voice (and hang up on a voice).

It uses a superset of the HAYES SMARTMODEM command set. I used the unmodified
Hayes driver for a while before changing it to also handle the USR
extensions. It also claims to be able to be used with CrossTalk, SmartCom and
PC-Talk communications software, but I was unable to test this. (I presume
it will work, as it looks like a hayes)

It does pulse or tone dialing and if tone dialing doesn't get rid of
the dialtone, it will try pulse dialing.

The warranty is 2 years from US Robotics. The dealer will also handle
warranty repairs (by sending you a working one and sending yours off
to the factory.)

The 1200 baud performance was much, much better than our Racal-Vadic
MACS dialers. We were able to connect to sites with the USR modem that
we could not get to with the Vadic modem. There was very little noise
at 2400 baud and virtually none at 1200. I successfully connected at 2400 baud
to ATT, Concord Data Systems, Vadic and USR  2400 baud modems, so there is no
interoperability problem. This also worked at 2400 baud on our ITT WATS lines
which are much, much noiser than ATT WATS (then again, they are also much
cheaper, you get what you pay for). I expected it to have problems with the
noisy ITT lines, but it worked perfectly. I wasn't able to give it the acid
test of trying to use Sprint, but then nothing works on Sprint reliably...

Physically, it's 6" x 10" x 1". It's a very nice, low profile modem.

The dealer is the major east cost distributer for US Robotics and
has many units in stock. We received ours within days of placing
the order.

The $399 price is ONLY available from the following dealer.
Any other dealer will probably charge you more.

The dealer is:
	Advanced Data Products, Inc.
	18974 Bonanza Way (B-3)
	Gaithersburg, MD 20879
	(301) 424-9490
The salesmans name is:
	Don Parnell

You can probably pay for the cost of the modem in the savings in a few
months phone charges.

It sounds too good to be true, but I've got a couple in the computer room
proving they are real.


>I resently posted an inquiry about "inexpensive" modems, because
we wanted to purchase several.  These are the responses
I received from the inquiry.  I want to thank all the folks who 
responded.  It helped us a great deal in making our selection.


	David C. Bennett
	SCI Systems, Inc.
	{decvax, akgua}!mcnc!rti-sel!scirtp!dcb

From: rti-sel!mcnc!ulysses!t12tst!chip (Chip Rosenthal)

I've got a pair of USR 2400 modems, I'm pretty happy with.  I've been
using them for a lot of talking with another site about 120 miles away.
They have worked very well when the other site uses USR 2400's.  However,
when the other place had Hayes 2400 I couldn't get a 2400 baud connection.
I suspect the Hayes, but I don't have one in-house to play with.


1)  the DIP switches are underneath.  Real pain when you have six modems
    stacked up in the bowels of a VAX like I do.  You can't see or set
    switches without pulling the whole fricking thing apart.

2)  the volume control is a slide control with a press-on knob.  i've
    knocked it off before.

3)  i can't figure out any reasonable way of dealing with a lot of them
    due to their packaging and those %*^$@$# power supply transformers
    all modem manufacturers seem to use.  about all i can see is that
    you stack them, dangle cords all over the place, and hope that you've
    got enought AC outlets for the transformers.

4)  One of our two modems arrived DOA.  Repair went OK.  Took about two
    weeks, which I suppose is reasonable, but I would have been much happier
    if the distributor appologized profusely and gave me a brand new one

In spite of all these things, I would have no qualms buying them again.
This might suprise you, but the problem which irks me the most is #3.
If I could find a good way of storing these turkeys it would keep #1
and #2 from being intolerable.  I'm willing to chalk #4 up as bad luck
and catagorize it as reasonable response.

What is good about them is that they seem pretty noise tolerant, they
seem to establish connection and baud rate reliably.  It has two commands
I really like.  The ATX6 tells me what is going on with the modem.  BUSY,
RINGING, etc.  The answer I like best is VOICE.  That's always good for
a moment's panic.  (Especially when I'm doing my dialing at 1:30am.)
Also it has a command to display the current settings, which is obviously
useful.  (It impressed me, but then again I'm used to working with Hayes

Is there a reason why you aren't considering Hayes 2400, besides cost?
Do you know something I don't?  (PS.  I wouldn't mind being forwarded
a copy any interesting messages you might receive.)


Chip Rosenthal, Intel/Santa Clara, (408) 496-7651

Stan		uucp:{ihnp4!shell,rice}!neuro1!sob     Opinions expressed
Olan		       here are ONLY mine &
Barber		CIS:71565,623   BBS:(713)660-9262      noone else's.

John Quarterman,   UUCP:  {ihnp4,seismo,harvard,gatech}!ut-sally!im4u!jsq
ARPA Internet and CSNET:  j...@im4u.UTEXAS.EDU, formerly j...@im4u.ARPA

Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.3 4.3bsd-beta 6/6/85; site im4u.UUCP
Path: utzoo!watmath!clyde!cbosgd!gatech!ut-sally!im4u!jsq
From: j...@im4u.UUCP (John Quarterman)
Newsgroups: net.periphs,,net.lan
Subject: Re: 2400 (or higher) baud modems (4 of 4)
Message-ID: <670@im4u.UUCP>
Date: Sun, 24-Nov-85 15:24:22 EST
Article-I.D.: im4u.670
Posted: Sun Nov 24 15:24:22 1985
Date-Received: Thu, 5-Dec-85 04:24:44 EST
References: <632@im4u.UUCP> <667@im4u.UUCP> <668@im4u.UUCP> <669@im4u.UUCP>
Reply-To: j...@im4u.UUCP (John Quarterman)
Organization: U. Texas CS Dept., Austin, Texas
Lines: 557
Keywords: Hayes, Multi-Tech, Racal Vadic, Penril, ATTIS, Concord, CTS, etc.
Summary: More modems; more explanations of CCITT V.22 bis.

Here's what's left.  Be sure to notice the date on each message before
depending on it for ordering information.  Some of these are a year old.
One is the oft-quoted survey of December 1984 from Bruce Factor.
It's reposted here in the interests of reducing the number of times
it gets mailed around from person to person.  Not to mention historical
interest:  prices on 2400 baud modems have dropped by half within a year.

>From ut-sally!topaz!packard!cbosgd!ukma!david Mon Nov 18 13:35:09 1985
Date: Sat, 16 Nov 85 10:48:17 est
From: ut-sally!topaz!packard!ukma!david (David Herron, NPR Lover)
Subject: Re: 2400 (or higher) baud modems
To: im4u!jsq
Newsgroups: net.periphs,,net.lan,

The following are messages I've been collecting about 2400 baud modems.

We have 4 Multi-Tech 2224's here.  They were selected by the person
we feed in Cincinnati after he looked at all the modems he coiuld
get his hands on.  These modems do NO error correction protocols,
which was a conscious decision because he was having terrible problems
with the ones that did do error correction.

Date: 20 Dec 1984  06:52 MST (Thu)
>From: Keith Petersen <W8...@SIMTEL20.ARPA>
To:   Info-Cpm@AMSAA, Telecom@MIT-MC
Subject: 2400 baud modems

This is file 2400BAUD.TXT - relayed from the RCPM circuit:

>From:  Wayne Masters, Potpourri sysop
       (408) 378-7474 300/1200/2400 baud
       San Jose, Ca.

Subject: New 2400 baud modems         8/19/84

       Many of you have asked technical questions about the 2400 baud
modems now on the market (and more being introduced monthly).  As most
of you know by now Irv Hoff and I have been beta testing 2400 baud for
several months.  The test results are amazing to say the least.  Running
controlled tests on standard dial-up phone lines with random "noisy
connections", the number of "hits" on a given file transfer is less by
a factor of 10 using 2400 baud vs 1200 baud.  So it is concluded that
2400 baud technology is working and will soon be available on most
commercial and private dial-up systems.  Now, what is a "standard" 2400
baud modem?  

       You will no doubt see various technical descriptions of a given
2400 baud modem touting it's features.  Be sure the modem you choose has
this specification:

       CCITT recommendation for a V.22 bis modem communicating at 2400 bps.

       Further explanation of this CCITT standard:
Frequency- Bell 212A
Encoding modulation-  16 level psk  (quadrature AM or QAM)

       This sounds a lot like the Bell 212A standard for 1200 baud--and it
is.  The difference is in the encoding or modulation scheme.  Bell 212A 1200
baud uses 4 level psk and 2400 baud uses 16 level psk.  If you "listen" to
the 2400 baud carrier it will sound exactly like the familiar 1200/212A-
like "static" or a scratchy noise.

       Features to look for in your search for the "right" 2400 baud modem:

1.  Does it retain 300 baud bell 103 capability?  (most offer 1200 baud as
    a "fallback")
2.  Is it "smart"--a biggy if you intend to call other systems a lot.
3.  Does it offer autoanswer--a biggy if you run a remote system.
4.  Price--a real biggy

       So far, none of the modems on the market offer all these features
in a "standalone" modem.  That is one big reason why Irv Hoff and I have
been involved with Racal-Vadic--not only beta testing to prove 2400 baud
technology...but to get the features most users prefer designed into the
modem.  Others may follow some day but Racal Vadic will introduce their
"standalone" modem in time for Christmas 84 with the following features:

1.  Smart-autodialing.  It will recognize both the Hayes and Vadic commands.
2.  0-300 baud at both Bell 103 and Vadic protocols
3.  1200 baud at both Bell 212A and Vadic protocols
4.  2400 baud CCITT V.22 bis
5.  Price is expected to be $695.00 retail

      The first release will be an external RS-232 model.  Early 1985 will
see the single card slot version for IBM PC's and compatiables.

       In order for 2400 baud to be in "great demand" there must be systems
available for the users to access.  I am working with Racal-Vadic to 
identify RCP/M and RBBS systems where 2400 baud modems could be placed to
generate public interest in 2400 baud.  Sysop's should contact Potpourri
at 408-378-7474 if interested in participating.

       Now about software to support 2400 baud.

       Both MDM7 and MEX will support 2400 baud if the user modifies his
port overlay to setup his port for 2400 baud.

       For sysops who use BYE3, the problem is different.  Most 
implementations of BYE rely on the hardware's Data Available signal (DAV)
to trigger a check-for-carriage-return sequence at different baud rates.
If most hardware is like mine (Z80 SIO), if the hardware is set to look
at 300 baud and the modem answers at 2400 baud the DAV is never set and
you are in an endless loop.  Same thing happens if you set the hardware
to 2400 and the modem answers at 300.
       I modified BYE3 (version 26 and up) to handle TSTBAUD differently.
I chose to look at each baud rate in 2 second windows, 300 first, then
1200 and 2400, and loop thru this sequence until a C/R or L/F is detected.
The caller is never more than 4 seconds away from his calling speed but
must continue to issue c/r's until the familiar message "Nulls, if needed"
is displayed.  Sysop's who choose to use BYE3 need only add the "SET2400"
code into their port insert. 

       Well, enough for now.  Feel free to contact me if you are more
confused now than you were before reading this.

                     -wayne masters, Potpourri sysop-


End of TELECOM Digest

Path: ukma!qusavx!hasmed!cbosgd!ihnp4!houxm!whuxlm!harpo!decvax!genrad!mit-eddie!godot!harvard!seismo!brl-tgr!tgr!philabs!sbcs!bruce%cmcl2.u...@Seismo.ARPA
>From: bruce%cmcl2.u...@Seismo.ARPA
Newsgroups: net.micro.cpm
Subject: 2400 baud modems
Date: Thu, 27-Dec-84 09:16:05 EST

For those of you in the market to buy 2400 baud modems I want to
inform you of a great deal.  I would like to state that I am not
affiliated with ANY of these companies, and I am not receiving and
benefits by posting this information!

After spending a few days pricing modems I have compiled the following
information (saving the best for last).  If anyone has any additional
information I would greatly appreciate it.

We were interested in rack mounting them so most of the prices given
are for cards that would plug into a rack.  "box" refers to a stand
alone modem.

DEC     1 - (800) 962 - 3244

now     DF112-AM        300/1200        card    $ 506
now     DF126-AM        2400 only       card    $ 634

Racal Vadic     1 - (800) 482 - 3427

now     VA212PAR        300/1200        card    $ 445
3/85    VA4224          1200/2400       card    $ 740
now     VA1681          houses 16       rack    $ not priced yet

Concord Data Systems    (617) 890 - 1394
now     CDS224 AA/ORG   1200/2400       box/card$ 845           $ 825
now     CDS224 Autodial 1200/2400          "    $ 995           $ 975
now     CDS224 ARQ      1200/2400          "    $1295
now     CDS224 ARQ Auto 1200/2400          "    $1395
now     CDS224 Super    1200/2400          "    $1695
now     CDSRM-07A       houses 7        rack    $ 750

Hayes   1 - (800) 241 - 6492

now     Hayes1200       300/1200        box/card$ 499
2/85    Hayes2400       300/1200/2400   box/card$ none
now     08-00056        houses 6        rack    $ 766

Quantity Discounts are minimal.

Micom   1 - (800) 527 - 0204
                                                                Q >16
now     M3012           300/1200        box     $ 495
now     M3012 plus      300/1200        box     $ 595
1/85    M3024           1200/2400       box     $ 795
1/85    M3024 plus      1200/2400       box     $ 895           $ 805
  "        "                "           card    $ 845           $ 760
now     M3200           houses 16       rack    $ 750

General Datacomm                (203) 574 - 1118
                                                                Q 10 - 19
now     DC211AL         300/1200        box     $ 675           $ 595
 "         "                "           card    $ 585           $ 520
1/85    DC2412          1200/2400       box     $1195           $1050
 "         "                "           card    $1105           $ 790
 "      DS1             houses 16       rack    $ 795

Paradyne        1 - (800) 482 - 3333 or 1 - (800) 342 - 3532

now     DTU1200D        300/1200                $
now                     1200/2400               $ 900

NEC     1 - (800) 538 - 8166
                                                                Q 11 -20
now     N212BRL         300/1200        box     $ 795           $ 669
 "         "                "           card    $ 725           $ 606
 "      DSP2430         1200/2400       box     $1095           $ 976
 "         "                "           card    $ 965           $ 855
 "      N4083           houses 8 - 1200 rack    $ 625
 "      SR0801          houses 8 - 2400 rack    $ 900

QUADRAM         (404) 923 - 6666
                                                        Q > 3
now     QM10000         300/1200                $ 695           $ 625
not available           ?/2400                  $ 

NO Rack mounting.

Ven-Tel         1 - (800) 538 - 5121
Will Call me back.

                        300/1200                $
                        ?/2400                  $

Promethus       (415) 490 - 2370        (check 800)
Will call me back.

                        300/1200                $
                        ?/2400                  $

Fujitsu         (408) 946 - 8777        ext 576

not available           300/1200                $
now     F1935B          1200/2400               $ 895


CTS Datacomm    (203) 743 - 3681        Pete Coccaro
        Distributor:    Professional Network Services
                        Harvey Schlesinger      (617) 449 - 6460

Model:  CTS2424AD

These people had by far the best deal.
The list price for the Stand Alone (box) modem is  $ 795
The list price for the (rack) mounted modem is ~$ 700.

Besides starting off $ 200 less than everyone else their
quantity discounts are very good.  The Stand Alone modem
will be available starting January, and their rack mount
modem should be available February.

Here is a Quantity discount price list.

Quantity	%dicount	S.A.	rack
========	========	====	====
    1		   list		$795	$700
  2-5		   10 %		 716	 630
  6-10		   20 %		 636	 560
 11-25		   25 %		 596	 525
 25-		   30 %		 556	 490

For all of you usenet sites that are still running 1200
(or possibly even 300) the modems will pay for themselves
very quickly.

>From all of the literature that I have recieved here are
a few of the advantages of this modem above the others:

1) works at 300 or 1200 or 2400 asyn	(others only 1200/2400)
		   1200 or 2400 sync

2) Stores 10 numbers (40 chars each)	(others only 1)

3) For tone dialing it dials ALL 12	(others only can generate 
   tones including (* and #)		 numbers 0-9)

   This last one caused a nasty problem when we needed to
   generate the extra tones because some of the sites we talk to
   have switching systems that require them (Gandalf).

4) Will automatically change the speed   (some of the others needed
   to the other modem.			 a manual intervention).


usenet:  {philabs, allegra}!sbcs!bruce			Bruce Factor

Path: ukma!qusavx!hasmed!cbosgd!ihnp4!houxm!vax135!ariel!mdg
>From: m...@ariel.UUCP (M.GALE)
Newsgroups: net.micro.cpm
Subject: Re: 2400 baud modems
Date: Fri, 28-Dec-84 09:20:51 EST

Please note at the beginning that this is coming from an account
on an AT&T computer.
<Reach out and byte someone...>
Just wanted to point out that in the recent summeries of 
modems available people seem to be missing a major manufacturer
of modems -- A T & T.

Check it out with an A T & T - I S sales rep. They've got 
1200/2400 standalone and rackmount systems. And you don't
call it the Bell 212 standard for nothing.

Please note that I do not work in that department and know 
only the basics concerning such hardware i.e. it exists.

I am not an employee nor an authorized representative of
any part of AT&T, I only help solve problems for them on
a contract basis. To think that my opinions are those of
the company is ludicrous.

Michael D. Gale
"I just like blinking lights-the DECsystem 10 operator's panel
	is a work of art" blink-blink-blink-burnout-blink

>From r...@mgweed.UUCP (Randy King) Sun Feb  6 01:28:16 206
Path: ukma!cbosgd!ihnp4!mgnetp!mgweed!rjk
Newsgroups: att.general,net.unix
Subject: Framing errors and autobaud @ 2400

It seems that autobauding from 1200 down to 300 by means of a framing
error is quite reliable when the 300-baud user types almost any character.
Hence for years uucp info has contained strings like:   login:--login:
where the "--" implied "send CR".

The reverse did not work, so the 1200-baud user would send a BREAK to
upshift the remote to 1200; hence  login:-BREAK-login:  for the uucp info.

Now I am finding that downshifting from 2400 baud to 1200 baud more closely
resembles the 300->1200 upshift in that sending a BREAK is the more reliable
way.  It is not always the case, however.  There are times when just a CR
from my 1200 baud modem calling a tri-speed modem at 2400 baud will cause
the port to fallback to 1200.  Many times, however, a BREAK is required to
cause the downshift.

If you have had experience with 2400 baud autobauding, including upshifts and
downshifts among the speeds from 110->2400, I'd like to hear about your
findings.  This would be important information for future releases of UUCP
information from sites with >1200 baud modems.

						Randy King

>From W8...@SIMTEL20.ARPA (Keith Petersen) Sun Feb  6 01:28:16 206
Path: ukma!cbosgd!ihnp4!houxm!whuxl!whuxlm!harpo!decvax!genrad!panda!talcott!harvard!seismo!brl-tgr!tgr!W8...@SIMTEL20.ARPA
Newsgroups: net.micro
Subject: 2400 baud modem review
Date: Sun, 31-Mar-85 10:40:40 EST

The following review was not written by me.  It was downloaded from a
Remote CP/M system.  Unfortunately there is no way to reach the author
because it is unsigned.  It is presented here for its possible
informational value.  Please address discussions/comments to the
mailing list, not me.  I don't own a 2400 baud modem.

10 Mar 85


The products described here were repeatedly tested for a specific
application only.  No value was placed on advanced features not
directly related to their intended use.  The opinion expressed herein
is that of the reviewer and may, in fact WILL differ considerably from
other reviewers' opinions.

This is an unsolicited review.  Anyone able to disprove the reviewes
claims is welcome to do so.  This review is about as unobjective as it
can get.

	In a data processing environment, chances are the employee
with a terminal and a modem (or computer) and access to the business
computer via dialup will be more productive and is more likely to put
in a few hours' worth of unsolicited overtime per week than the
employee who has access to the same computer only during working
hours.  Therefore, it was decided that the office computer be set up
with at least one high-speed dialup line and the most economical
choice was that of a 1200/2400 baud modem.

	The modems were going to be used for two purposes:
   1. unattended autoanswer
   2. occasional use for dialout

	Testing was started as soon as modems became available through
a local distributor.  Due to this factor only two brands were
evaluated. Here is the story on both of them:

1. PENRIL 2024

	The Penril 2024 seems to be the first widely available
1200/2400 baud modem, with the exception of the prohibitively priced
VADIC 4400 series.  The 2024's list price is somewhere around $900.

	The 2024 offers two baud rates, 1200 and 2400.  The 1200 baud
protocol can be switched from 212A to V.22 at configuration time.  By
today's standards, the 2024 cannot be considered a "smart" modem in
that its smartness is limited to the ability to dial a phone number.
Placing the modem in autoanswer mode is accomplished by simply
configuring the internal and external switches according to the
manual, releasing all front panel switches and plugging it in.  The
2024 does not have a power switch (a definite plus in this

	Originating a phone call with the 2024 is a cumbersome
procedure, especially in an application where the modem may be 100
feet away from the terminal.  First, the modem must be taken out of
autoanswer mode by pressing a front panel switch.  Next, the originate
baud rate must be selected by locking the HI/LO switch IN or OUT.
Note that if you set up the modem for 2400 baud, you can call a 1200
baud number because of the "fallback" feature.  You just have to
adjust your terminal baud rate after connect.  The 2024 has no abort
provisions.  While dialing, the TALK/DATA switch can be used to abort.
When connected, you must either cause the remote computer to drop
carrier or you again have to hit the switch.  An alternative is
dropping the DTR line low, but in some instances that's a bit hard to
do.  Dialing a phone number is very awkward. The sequence is
"CRNnnnnnnn<CR><LF>" so to dial 555-1212, you type CRN5551212^M^J.
Fine if the ENTER key on your keyboard generates a CR-LF sequence;
with most terminals you have to hit two keys.  Sorry, no redial

	The Penril worked fine calling the local TYMNET 2400 baud
access number, but no connection was established to any long distance
modem at 2400 baud.

	The modem is superbly suited for unattended autoanswer mode.
the 2024 can be turned on and left alone and if something goes wrong
it's the software but not the modem.  The continuous high-pitched
noise coming out of the built-in speaker may be objectionable to
some -- it picks up the strongest local AM radio station.  the
speaker can be turned low or off via an internal jumper block.

	One 2024 modem was tested initially in early November 1984,
and two were again tested in late February 1985.  No difference was
found between the three modems, even though the early onemay have been
a preproduction unit.

>From neuro1!...@rice.ARPA Sun Nov 17 03:22:35 1985
From: Stan Barber <neuro1!...@neuro1.ARPA>
Subject:      modems

Thought this might be of interest
-------- begin included text ----------

Path: neuro1!shell!ut-ngp!ut-sally!seismo!lll-crg!dual!ames!jaw
From: j...@ames.UUCP (James A. Woods)
Newsgroups: net.dcom
Subject: Paul Baran, modem hero
Date: 26 Jul 85 00:55:36 GMT

# fools speed ahead

that amazing telebit/dca 10kbit modem sure seemed like a minor miracle
(infoworld, 7/22), so i called telebit for the technical dope.

if the literature is to be believed, bad lines don't really faze the thing.
i'm sure a few usenet sites with $2300 would jump for it.
is it time to ring the death knell for CCITT modems, which, because of noise
and gross fallback strategies, never reach their max throughput?

hmm ... "packetized ensemble coding...inventor lists airport metal detector,
invention of packet switching in 1964, and co-founding of equatorial
communications (your friendly neighborhood spread spectrum service)
among his credits".  no slouch here.

dca stock (telebit is private, but marketer dca is public) has risen to
around $30 of late, from about $22 a few weeks back.

oh, the dope -- 

	- 512 carrier freqs. each modulated with either 6-bit or 4-bit QAM,
	  or 2-bit QPSK, depending on SNR.

	- adaptive duplexing, to take advantage of the one-way burst
	  nature of most traffic.

	- fallback in decrements of < 100 bps.
	  (successive rate halving of the v22 standard is the real killer
	   on dialups.)

	- bell 103, 212a, and hayes command language compatibility

	- call (800) telebit


Path: neuro1!shell!ut-ngp!ut-sally!seismo!harvard!talcott!panda!genrad!decvax!decwrl!dec-rhea!dec-beta!dieter
>From: die...@beta.DEC
Newsgroups: net.dcom
Subject: Info on DEC DF224 \"Scholar\"
Date: 30 Jul 85 18:52:17 GMT

2400 bps modems - reply

>I was wondering about the compatibility of 2400 baud modems.
>1) What different types of protocols are there, or aren't there?
>2) Specifically, we have a bunch of ATTIS and Concords, which
>   are compatible, but how compatable are they with DECS new
>   DF-224s?
>3) Which ones perform well, and which ones don't.
>4) Is there a prevailing standard, or does it look like there 
>   is going to be one.

1. Most modem vendors offer their own autodial protocol.  Lately many have been
implementing the Hayes protocol also, in one of two ways.  One way is to offer
two models, one with Hayes and one with their own.  The other is to put the
choice in the modem(Penril does this).  At Interface many vendors criticized 
the Hayes protocol but sheepishly admitted that the marketplace demanded it.
   The DF224 does not support the Hayes protocol, it is unique like the ATTIS
and some others.

2. The DF224 was tested with the CDS, Hayes, and Vadic it should be compatible 
with any other V.22bis modem - especially if it uses the Rockwell chip set
(most of the market).

3. Of course the DF224 (Scholar) performs the best!  What else could I say...
Actually most of the V.22bis modems will be very similar, and we would expect
all of the modems made with the Rockwell chips to work the same.

4. I presume the standard referred to is the Autodial method.  The perception is
that the Hayes autocall method is the most widespread...don't know if its true
but it perceived to be so.  Mostly due to Smartcomm software making life easy
for PC users.  The DF224 autocall method is very easy to use and the modem
has an extensive menu, 15 stored numbers, redial, nametag calling, etc.  I 
notice that the Hayes 1200 and 2400 versions are different, I wonder how much
pain that has caused users wanting to upgrade.

The initial question was about compatibility, I think you will find most of the
recent V.22bis modems will be very similar.  Most will also implement the fall
back mode to be Bell 212A compatible rather than V.22.  Those that adaptively
equalize to the line in 1200 mode will work where a 212 will not.

Ralph Dieter
Merrimack, NH

John Quarterman,   UUCP:  {ihnp4,seismo,harvard,gatech}!ut-sally!im4u!jsq
ARPA Internet and CSNET:  j...@im4u.UTEXAS.EDU, formerly j...@im4u.ARPA

			  SCO's Case Against IBM

November 12, 2003 - Jed Boal from Eyewitness News KSL 5 TV provides an
overview on SCO's case against IBM. Darl McBride, SCO's president and CEO,
talks about the lawsuit's impact and attacks. Jason Holt, student and 
Linux user, talks about the benefits of code availability and the merits 
of the SCO vs IBM lawsuit. See SCO vs IBM.

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