Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site brl-tgr.ARPA Path: utzoo!watmath!clyde!burl!ulysses!allegra!bellcore!decvax!genrad!panda!talcott!harvard!seismo!brl-tgr!tgr!andy@aids-unix.ARPA From: andy@aids-unix.ARPA (Andy Cromarty) Newsgroups: net.ham-radio Subject: Re: Ham Programs & BBoards Message-ID: <8392@brl-tgr.ARPA> Date: Thu, 21-Feb-85 01:58:31 EST Article-I.D.: brl-tgr.8392 Posted: Thu Feb 21 01:58:31 1985 Date-Received: Tue, 26-Feb-85 08:22:52 EST Sender: news@brl-tgr.ARPA Organization: Ballistic Research Lab Lines: 76 Walt, The Red Cross in Palo Alto has committed pretty heavily to the packet radio system produced by the Tuscon Amateur Packet Radio (TAPR) group. TAPR has a board (a "Terminal Node Controller," or "TNC") that comes as a kit for something like $300. Heath has just announced their own kit version of the TAPR design for the same amount, I believe -- see this month's 73 magazine. The TAPR TNC's are professional-quality design, good-looking, and work like a champ. One end plugs into your radio (usually your HT), the other end plugs into your computer terminal (or your home computer running a terminal emulator program), and you're on the air. Done. Sit down and type; QSO in progress. Since you say your guys have home computers already, all they need is the TAPR or Heath "Terminal Node Controller" and the program that lets their PC act as a terminal to another computer. There are other vendors of packet systems, perhaps most notably AEA (who makes an assembled version of the TAPR board for five or six hundred dollars) and GLB (which makes a low-end system with much or most of the TAPR TNC's capability for fewer dollars.) We have put together a complete package for our own (Red Cross) use in a single aluminized attache case that includes a small Texas Instruments terminal with thermal printer, a TAPR board, and a 2-meter HT; you can carry it in one hand. (It does require 120 volt AC; we're working on a 12-volt version.) It's pretty straightforward to assemble this sort of package, if you decide you need it for Red Cross disaster services operations. We have also used it for Simulated Emergency Test, the county-wide Medical Exercise, and other drills, and we've learned a lot about how packet can be used for emergency applications (including the problems it doesn't solve). Overall, it's a very impressive thing for a fire marshall or police chief to be able to *see* printed radiograms being sent back and forth between emergency stations -- it usually beats anything they have at their disposal for disaster communications hands down. The next step is to put up repeaters in your area, once local hams can converse via packet. This is a least as easy as putting up a regular two-meter repeater. As a matter of fact, every TAPR board *is* a repeater (a "digipeater") without you doing anything special to it, at the same time that it's your personal TNC, so you can get along for a while without installing special high-level repeaters in your area if everyone is within 2-meter FM simplex distance of the next guy. Most of us who work for the Red Cross leave our stations on the air 24 hours a day as digipeaters; if I want a QSO when I get home from work at night, I just sit down at my terminal and type -- everything's all warmed up and on the air. In many cases you can extend you range by going through existing duplex 2m FM repeaters; some of us do this now in the San Francisco area. It's not optimal, but it often works. The problem of how to link into the existing National Traffic System is being worked on. Suffice it to say that we aren't there yet. The currently implemented approaches are, unfortunately, "think small" approaches, and we still lack a good model of what such a system should look like on a national scale and what its high-level protocols should be. There are some systems in place now that provide a limited capability for NTS traffic passing via packet, mostly in the Northeast; they suffer from the disadvantage of being utterly ad hoc but offer the advantage of giving people exposure to the idea of traffic-via-packet now. (Admittedly an opinion, but I design and build distributed artificial intelligence systems for a living, so I allow myself the luxury of holding such an opinion.) Some of us here on the west coast (emergency comm people, traffic handlers, and packeteers) are working on a general solution to this problem that can be implemented on a national scale. (Anyone who's interested is more than welcome to participate in the design process, by the way; there are a lot of hard problems to solve before we're all linked together -- it's not just a matter of more repeaters and more mailboxes -- and we need all the good networking ideas we can get.) Good luck & 73, Andy N6JLJ AEC, Palo Alto Red Cross