Packet is too slow

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Left, TI-92. Right, HP48 series. Photos not to scale, the TI-92 is approximately the size and shape of 2 HP's side-by-side.

This stuff isn't really useful, but it sure is cool! (Updated 4-22-99 8:46 PM)

On a whim I went and bought a whole load of fine packet equipment, I was thrilled! Now I could experiment with wireless data, no more telephone line to keep me in my basement. Unfortunately after I had bought it all I found out that there is very little packet activity in Utah. Sure there's a PBBS or two but who cares? PBBS's are boring. Anyway, until I find someone else to "play" with I'm on my own. The only way I can experiment with packet radio by myself is if I have both ends of a packet connection.

I have a Yaesu FT-50RD handheld radio and a Yaesu FT-8500 mobile radio, a Paccomm PicoPacket TNC w/ internal GPS and built in battery pack and I also have a Kantronics KPC-9612 dual port TNC for simultaneous 1200 bps and up to 38400 bps data. I spent all my money on those - I'm broke! I almost have enough stuff for both ends of my experimental packet link, the only thing I was missing is a second computer. I was just going to have to figure out some other way to do it with just my computer. This got me thinking, to do packet I don't really need a full-blown pentium jalopy, a dumb terminal will do just fine. This is where the calculator comes in. Confused? Go straight to TAPR's packet page or check out everything they've got at their Home page

If you can get your calculator to cooperate as a terminal, you'll be able to use a standard external modem to dial-up your ISP and access your shell account for email, IRC, usenet, and even the web if you use lynx. The calculator doesn't really care what kind of modem it's connected to, you can even use a TNC for a *really* small packet radio station. I can fit my calculator, my TNC and my radio all in a fanny pack sort of thing I got at Radio Shack for $15. I think they called it a "Comunications Belt". It has a radio pouch that's the perfect size for my Yaesu FT-50RD (Check out Kenwood's TH-D7A, it's handheld radio with a built in TNC), a pocket for my Pico TNC, another for extra batteries, you get the idea. I like to take the whole setup with me when I go hiking so I can have something to do when i take a break.

It would be nice if we could all afford palmtops, they're small and can do everything the calcs can, so why bother with a calc? Simple, the most expensive calculator available is the TI-92 at $160-$200, good luck finding a palmtop for less than $300. Which calculator do you need? Right now, because of software availability, you only have two choices: HP48 series or TI-92.

If you plan on buying a calculator specifically for this project, consider getting an HP48 which is approximately $100. It will be alot cheaper and a bit easier to interface with because the HP's have an RS-232 port built in. The interface package offered by Hewlett-Packard includes a cable and a floppy disk with software and costs around $60, way too much in my opinion. I made the cable for $4 using a CD-ROM audio cable (has the right connector on it) and the software you can get for free on the internet. There are many diferent terminal programs to choose from, all with their own quirks so be sure to try more than one. You can find places to download software with HP48 FAQ, click the link at the end of the next paragraph.

The only drawbacks to using the HP48 are that it's hard to use, the display is uncomfortably small for terminal use, no "QWERTY" style keyboard which makes it hard to type with, it has a metal face-plate over the keypad that dents easily, and the protective cover that it comes with doesn't protect it very well (I've seen many smashed screens). It's designed for engineers and engineering students so user-friendlyness isn't one of it's selling points (maybe that's not so bad: there are thousands of brilliant people making good software for it). Most people who use it have no problem with toting around a 4 pound owner's manual with them everywhere they go. Just poke around on the internet for a while and you'll see that TI's really aren't all that cool if you're a power user. It's probably the most powerful calculator available.Confused? See The HP48 Frequently Asked Questions List (FAQ) for more detailed information. Also check out the software archive at www.hpcalc.org (thanks LennyNero).

If you're not a poverty stricken college student like me, then think carefully about the TI-92. This baby is beautiful, it has all the trimmings: the largest LCD in the industry, a real "QWERTY" keyboard so it's easy to type with, it even has a GUI with nifty pull-down menus (Graphical User Interface. Windows is a GUI, DOS is not). 10 minutes flipping through the manual and you're ready to roll.

Unfortunately, the TI's aren't perfect. HP's have a built in RS-232C (serial) I/O port so all you have to do is make a cable with the proper connections to your modem or TNC. Not so with the TI calculators, they use their own protocol in their I/O ports, partly to make it easier for 2 TI's to tranfer programs and also partly so that you have to buy their TI Graph-Link cable. The Graph-Link will convert TI-speak to plain RS-232 so it can talk to your computer. It's designed to connect to your computer so that you can download programs from the internet, store programs on your hard drive when your calculator's memory fills up, etc. In order for you to connect to a modem or TNC with one you absolutely have to use a bona-fide, store-bought TI Graph-Link cable (the software is free). No home built pieces of crap will work for this project, so forget about saving money. The price on the Graph-Link has dropped from $60 (same as HP's link system) to about $35. Your choice for terminal programs will be easy, you have no choice: it's Fterm or bust! Fterm is packaged with the Fargo shell for the TI-92. You can download Fargo in the Linux package or in the DOS package For more info, see www.ticalc.org.

TI-92	HP48
Easy to read LCD Large keyboard Tough and rugged Very user-friendly More expensive	Smaller and lighter Cheaper More powerful More software choices Pain in the ass to figure out

OK, so how do I make it work?

Now if you understood all the pros and cons of TI's and HP's and you have your calculator in hand, then your ready to actually connect it up. I tried using the HP but I have no manual and I was annoyed by the small screen, AND since I already had a TI-92, I decided to take the easy route and use my TI. If all you want to do is connect you calc to an external modem then this is going to be very easy, all you have to do is download Fargo from www.ticalc.org and install it using the included instructions. Then, you'll need to put a 25 pin serial male-to-male adapter AND a 25 pin null-modem adapter on your Graph-Link and plug all that into your modem. What's that you say? your modem isn't doing anything yet? well, turn on your modem. You'll know if everything is ok of you see "ok" on your calculator's screen when you turn the modem on. This means your modem is now ready to receive Hayes standard "ATZ" command strings, use these to dial, hangup, etc.

Now that you can use your modem with just a simple terminal, calculator or otherwise, you're ready to try something really cool, if you have two TNC's. Using another null modem adapter, connect one TNC's serial port to your modem's serial port, don't forget the null-modem adapter! My KPC-9612 works great because it has a 25 pin serial port identical to the one on your average modem. If your TNC is different, like a pico that has a modular plug, you'll have to make an adapter for it. OK, your KPC-9612 (or similar) is connected to your modem with a null modem adapter, this ensures that whatever your modem transmits will be received by your TNC and vice-versa. Hopefully you have another TNC to take portable with you, I use my Pico which is connected to my TI-92. From my portable TI-92 packet station I can connect to my TNC at home which just so happens to be connected to my modem but in order to activate my modem and tell it to dial my ISP I have to be able to pass plain vanilla ASCII to the modem. For example, after I've connected to my home station I can give my home TNC commands as if I were right there at home. In order to do this, you must put your home TNC into "transparent mode". This is usually accomplished by typing the "trans" at the command prompt. (to get out of transparent mode, press [ctrl]-c three times). That way, all the text that your home TNC receives will be passed unaltered to your modem. You can change all the parameters of your home TNC remotely if you set it up for remote administration. You better do it so you can turn off transparent mode, after all, somebody might decide to hijaak your internet connection!

If you get everything up and running, you'll probably wonder how the hell you're supposed to take all that stuff portable with you if you have a couple pounds of chained adapters to monkey with. Well, being the experienced techy-guru that I am, I got some adapter schematics and matched those up with the schematics in my TNC/modem manuals and I made my own from the adapter kits that Radio Shack sells. They're a piece of cake, all you have to do is make sure you wire it up right, there's no soldering or anything. Just snap it together and plug it in. I may be a guru, but I always make mistakes. Mine didn't work the first time and neither will yours, so check it all over and fix it.

OK, that's all I can think of to say about this for now. I'm certain that I've missed something. Maybe I should put some pictures or something here. If you attempt to duplicate my station and you feel like there isn't enough info here to do it, drop me a line at qwasty@hotmail.com and I'll see what I can do to help you out and/or fix my site. For the IRC users, my nick is badon on EFnet.

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