"Joseph C. Pistritto" <jcp@cgch.uucp> (05/31/90)
A significant problem for upgrading TDD's is the installed base. I
bet there's a lot of these out there, so any new device would have to
speak 45 baud as well as 300 or 1200 or 2400 or whatever. Now
actually, this is more of a problem than you think. Most baud rate
generator/modem chips don't support baud rates below 110 any more, and
if they do the only choice is usually 75, (used for lots of newswire
services, maybe even still for Telex). Also, this is a 5 bit code if
I remember correctly, and lots of chips don't support 5 bits any more
either. This would probably complicate the design by several more
chips than would otherwise be needed, raising the price. I don't know
what the average income level of a deaf person is, but I bet it would
take a while for this idea to gain acceptance. Although I'd think the
the ability to use online services like Compuserve and BIX would be
work something to at least a reasonable number.
Joseph C. Pistritto (cgch!bpistr@chx400.switch.ch, jcp@brl.mil)
Ciba Geigy AG, R1241.1.01, Postfach CH4002, Basel, Switzerland
Tel: +41 61 697 6155 (work) +41 61 692 1728 (home) GMT+2hrs!AMillar@uunet.uu.net (06/01/90)
I understand that making a dual purpose modem, with both 45bps BAUDOT and 2400bps ASCII for example, is going to cost a little more, but I do not believe it could cost very much. I just bought a 2400bps modem off the shelf of the local electronics store for $99. They can make modems cheap through mass-production, using standard modem chipsets. If 45bps BAUDOT were added to the modem chipset, then it may add maybe $20 to the cost of the modem. So then it's $120 instead of $99; still no big deal. Think of what things would be like with dual-mode modems. Service providers could use dual-mode modems to accept calls from regular modems or TDDs. BBSs, Telenet, Tymnet, public-access Unix systems, you name it. That way, every deaf person could read the Telecom Digest, and all the rest that the online world offers. Next, deaf people could start upgrading from regular TDDs to dual-mode modems. The modem would be the only thing you'd have to spend money on, because there are more than enough old glass TTYs that people are trying to get rid of. With the dual-mode modem, you could have higher-speed access to online services, and still communicate with all of the older TDDs. Even on interactive conversations between two TDDs, you could now have a faster conversation than before. I would make the modem so that it would have a phone jack and an RS232 jack. The RS232 side would always use ASCII, at a configurable baud rate (1200 to 9600, for example). You'd hook this up to an old VT100 or Televideo 920, if cost is an issue, or to a personal computer or 3B2 or whatever. The phone side would talk ASCII or BAUDOT, depending on what was on the other end. If it was a BAUDOT connection, the modem would automatically translate speeds and character sets. This couldn't be that hard, so why doesn't it happen? Is it simply the lack of a large, money-laden potential customer-base that keeps modem chip manufacturers from putting these features in? Maybe if we could convince other big modem users like Tymnet to want them, that would start the ball rolling to mass produce them. Just some food for thought. Alan Millar AMillar@cup.portal.com