Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!accuvax.nwu.edu!nucsrl!telecom-request From: "John R. Levine" Newsgroups: comp.dcom.telecom Subject: Re: Communications With The Deaf Message-ID: <3794@accuvax.nwu.edu> Date: 12 Feb 90 15:44:33 GMT Sender: news@accuvax.nwu.edu Organization: Segue Software, Cambridge MA Lines: 44 Approved: Telecom@eecs.nwu.edu X-Submissions-To: telecom@eecs.nwu.edu X-Administrivia-To: telecom-request@eecs.nwu.edu X-Telecom-Digest: Volume 10, Issue 96, message 6 of 10 In article <3754@accuvax.nwu.edu> you write: >While long distance discounts are available to deaf people, I am curious if >even more cost-effective methods exist. Now my question to the group is >this: Are there less expensive sub-voice-grade lines available or does Telex >or TWX still exist for long-distance communication? The good thing about TDD is that it is very cheap, since it uses technology from about 1950. The bad thing is that it is totally out of the data communication mainstream since it uses technology from about 1950. Telex and TWX are both quite alive and widely used for international messaging, although in the US hard-wired Telex terminals are disappearing in favor of store and forward services and hybrids that use dial-up phone lines between the customer and the Telex carrier. Telex per minute charges are not particularly attractive compared to long distance phone charges, and Western Union is widely reviled for the poor service now provided to Telex customers. Then there's things like Telenet's PC Pursuit and the Tymnet equivalent (Starlink?), which cost two to three cents per minute at off-peak hours. The various RBOCs offer intra-lata networks (ours is called Infopath) that technically, at least, should be able to offer similar low-priced service. Unfortunately, TDD users can't take advantage of any of them because they only support ASCII 300 baud and up, not the old telex scheme that TDD uses. One possibility would be to lobby Telenet and Tymnet to put some TDD modems at their Pursuit and Starlink concentrators. Probably more productive would be to produce a second generation of TDD terminals that handle both the old Telex signalling and 300 baud 103 signalling. It shouldn't be too expensive; the guts of a 103 modem are now available in commodity chips and the code conversion between baudot and ASCII is easily handled by an 8051 or other controller chip. Perhaps someone can persuade a public-spirited chip vendor to make a chip or two that combine the keyboard scanner, display controller, and modem of a TDD II. Regards, John Levine, johnl@esegue.segue.boston.ma.us, {spdcc|ima|lotus}!esegue!johnl