3B2/modem recommendations wanted

[Bill Kennedy]

bob at MorningStar.Com (Bob Sutterfield) writes:
Following up what jiro at shaman.com (Jiro Nakamura) writes:
[who's following up Bob Izenbergs 3B2 modem question, deleting most of it... ]

Jiro>>   Also, Telebit can only do spoofing in PEP mode, right - so that
Jiro>>   rules out compatibility with other modems....

Bob>The T2500 (firmware rev 7 or better) and T1600 can spoof over V.32
Bob>connections if either MNP or V.42 error correction is operating.

Just a particle of input here since I have tried the V.32 uucp spoofing with
a T-1600 into a T-2500.  As Bob points out it works and is reliable.  The
downside is that 800-900cps is the best transfer rate I have seen while the
same T-2500 to a TB+ gets 1400-1500cps on the same two machines using PEP.
I like the T-1600 just fine but the Trailblazers still haul the uucp freight
here.  Pursuant to Bob I's original question here's my $0.02 for others with
similar curiosity.

Wrangler is an NCR Tower 32/400 but its serial card has some idiosyncracies
similar to a 3B2 (there's one of them here too).  All of the Telebits have
the capability to keep DCD high and dip it for some period of time after
losing "real" carrier, that's how mine are set up here.  Here's what I would
do in several different scenarios:

Lotsa money, mostly uucp, but full duplex (e.g. vi from/to remote) required
and maybe SL/IP or PPP - get a T-2500 and do your uucp work PEP and the full
duplex stuff V.32

Some money, almost 100% uucp - get a T-2000 (Trailblazer Plus) and stick with
PEP, live with the micropacket jerkiness or use 2400bps for full duplex

Money tight but gotta go fast, mostly uucp - get a T-1000 and ignore that it
will not do compression on the fly (which isn't much of a win anyway) or
better than 9600bps on the analog side of the line, same caveat for full
duplex.  The T-1000 is just fine for local PEP calling and light duty long
distance, the speed difference for a T-2000 in my case (99.9% LD) pays for
the $$ difference in a hurry

Money tight, light uucp, heavy full duplex or SL/IP - get a T-1600.  It's the
cheapest one in the line, it won't do PEP.  As long as you have a V.32 uucp
neighbor you're OK, transfer rates are decent, and in my limited experiments
the V.32 performance is OK.  Over a SL/IP link I've seen repeatable ftp
transfer rates of 1600cps, 800-900cps best case uucp, worse if you don't
enable spoofing.

I have five Telebits, two external T-2000s (in use 'round the clock) and a
T-1600 (ditto) on wrangler, an internal TB+ in the luggable road warrior,
and a T-1000 that "floats" from machine to machine for temporary PEP use.
If I could only have one modem it would be a T-2500.  If I could have only
two it would be a T-2000 and a T-1600 (in a very close tie with the internal
TB+ for the luggable).  If I had all or mostly local uucp connections and was
near-broke I'd have a T-1000 but if I did any BBS type stuff I'd look at a
US Robotics Dual Standard (I don't know if it can do DCD stuff like Telebits
can).

Sorry for the bulk, but the question comes up from time to time and the
water gets muddier as new and different models are introduced.  BTW another
nice thing about Telebit is better than average tech support, free firmware
fixes for bugs, and reasonable (IMHO) charges for firmware upgrades.  I hear
that the myriad of firmware rev levels on the T-2500 is something of a
headache but I don't have one so I don't really know.
-- 
Bill Kennedy  uucp      {att,cs.utexas.edu,pyramid!daver}!ssbn.wlk.com!bill
              internet    bill at ssbn.WLK.COM   or ssbn!bill at attmail.COM