Xref: utzoo comp.dcom.modems:9349 comp.sys.att:12178
Newsgroups: comp.dcom.modems,u3b.tech,u3b.misc,comp.sys.att
Path: utzoo!utdoe!contact!robohack!woods
From: woods@robohack.UUCP (Greg A. Woods)
Subject: Re: 3B2/modem recommendations wanted
Organization: Elegant Communications Inc.
Date: Sun, 21 Apr 91 20:17:48 GMT
Message-ID: <1991Apr21.201748.27415@robohack.UUCP>
References: <a50i11w164w@dogface>
Lines: 52

In article <a50i11w164w@dogface> bei@dogface (Bob Izenberg) writes:
> I'm going to be in the market for a modem for a 3B2/400 in the near
> future.  Telebit is a likely choice, but I'd like some other options.
> When I last looked, Hayes support for 3B2s wasn't the best.  The modem
> that I go with should do at least 2400 baud, and should be able to have
> DCD true all the time, dipping DCD and then raising it when a valid carrier
> is detected.  Transparency to uucp 'g' is a must.

Hmmm...  First off, unless you have an older, broken, version of
HDB-UUCP, then you *don't* need to have DCD high.  On the other hand,
if you do have an older, broken, version of HDB-UUCP, you need a
relatively smart modem that can hold DTR up normally, but drop it for
a few seconds when carrier is lost (i.e. when it hangs up).

Some other folks who followed up have suggested Telebit modems with
their PEP support and UUCP 'g' protocol spoofing.  I don't think
that's what you meant -- I'd guess you only want to run UUCP 'g'
through your modem, and you would like at least 2400 bps throughput.

I'm currently running two Hayes modems on this 3B2/400.  I certainly
don't have them set to assert DCD continuously either.  They work fine
for the most part, *BUT* they occasionally hang the port.  I'm not
sure whose "fault" this is, but I suspect the modems are part of it,
since I've used other modems with no problem.

Periodically, usually after conversing with a Telebit modem of some
sort, and after going on-hook, the RD and SD, or sometimes just the SD
light will go on solid.  However, there seems to be no actual traffic
through the port.  At the same time connecting to the port with cu
results in nothing.  Temporary disconnection of the RS-232 cable does
nothing to help.  Disconnecting the RS-232 and re-setting the modem
also does nothing.  Attempting to drop DTR via 'stty 0' does nothing.
The only thing that seems to restore normal operation (short of
re-booting) is to re-set the modem while the RS-232 is still
connected.

For the record, I have a Hayes SmartModem 2400 and a Hayes V-Series
SmartModem 9600 currently attached to an EPORTS card.

> Any comments about pricing, support, reliability or anything else are
> welcome.

The very best 2400 baud modem I ever used anywhere, including on the
3B2 was an AT&T DataPhone II 2224B.  It had the smarts to be able to
run with DTR as I describe above, and seemed to *always* work with
exceptional reliability -- until it took a lightning bolt in the phone
jack....  :-(
-- 
						Greg A. Woods

woods@{robohack,gate,eci386,tmsoft,ontmoh}.UUCP
+1 416 443-1734 [h]   +1 416 595-5425 [w]   VE3-TCP   Toronto, Ontario; CANADA