Tuesday, June 29, 2010

Plug-n-play APRS (not!) and lack of APRS documentation

Gary Hoffman, KB0H writes on the ARRL web site (The Amateur Amateur: APRS, the Beginning):
"I was still interested enough in APRS that I Googled it the next day. There were a great many sites dedicated to the field, so I skimmed a random sampling of them. Wow! Everything I read seemed highly technical, and none of it described what APRS actually was. The only solid piece of information I was able to garner was that if you called it Automatic Position Reporting System, the APRS Police would come knocking at your door. But just what was APRS? I still didn’t know.

Skip forward a few years.

The term APRS caught my notice from time to time, so I periodically went back to the Internet to see if I could figure it out. I didn’t have much luck. I did find a commercial Web site, byonics.com that sold APRS equipment, but all of the products seemed to be geared toward hams who already had a pretty good grasp of the subject."
I have to agree with him – the obvious places to find documentation for beginners (the Wikipedia page and, especially, aprs.org) do not have it. The wiki page goes quickly pretty deep into a technical network and protocol overview right after the introduction. aprs.org is a mess – it spends a lot of time complaining how APRS really isn't what most people are using it for, and doesn't really have any starting points. And there are broken links. The APRS Wiki has something, but it isn't very strong or up-to-date either.

G4ILO has written an article, APRS - Putting ham radio on the map, which I find pretty good – probably not the least because he says aprs.fi is "the best". It would be good to have this on the APRS Wiki.

If you manage to actually buy some hardware to use APRS, the configuration programs and menus are also very hard to use. I heard or read somewhere that some amateur clubs now have monthly meetings on the topic of programming radios (which actually means going through the menus to get settings right). The Byonics and Argent configuration tools show an awful lot of settings to start with. Most of the defaults are OK and you only need to fix your callsign and the audio levels, but it's way too easy to make configurations which break things for yourself (for example, by selecting invalid symbol codes instead of picking the symbol image from a table). Many misconfigurations actually break the network by transmitting way too often, or with abusive long paths.

I strongly think that the configuration programs should be improved to not accept any abusive or broken configurations. Also, they should initially only show the settings you really, really need to change (your callsign, comment text, TX audio level, and "pick a symbol image from this graphic table of images"). Most other settings should go to an "advanced settings" menu of some sort. Think Apple and the iPhone – to get regular users started it needs to be simple and lean. Path setting should, even in the Advanced menu, consist of a drop-down selection of "1 hop", "2 hops", or "3 hops" which would translate to something like WIDE1-1,WIDE2-2 somewhere behind the scene (with maybe a checkbox for "use TRACE instead of WIDE"). Free-form path entry should be in the Very-Super-Advanced configuration file, and even then the tracker firmware should refuse a WIDE3-7,TRACE9-9 path.

If you're looking for a little programming project, I'd guess Scott wouldn't mind if someone would improve the OpenTracker Windows config program a bit. It's Open Source, after all.

I suppose I should look at my software, too. aprs.fi doesn't have a proper beginner's guide, either. Or an user's manual. There are only 4 tooltips, and 14 help links (which are not localised). Awful.

theborg989 has uploaded a nice introductory aprs.fi video on Youtube. It could use a sequel which would describe things like tracking multiple stations and using the tools in the top right corner of the display.


Unknown said...

Thanks for the mention of my article. I wrote it in response to the number of people who have said that they had heard of APRS but couldn't find out what it was useful for.

Unknown said...

It's pretty tough to put information about APRS on wikipedia, as they have rules about only using information from a reputable source. Information from websites and such is not considered reputable, and as most of the information about APRS is contained on websites, you really can't post much. There's really only one book about APRS to reference, and that is Stan's interpretation of APRS.

I'm not really sure how newbie you really need to go. Do you go right down to describing what radios, computers, the internet, weather, and events are?

The descriptions I've read seem to do a good job telling that it's a real time tactical tool using amateur radio to transmit digital signals over the air.

If you don't know what amateur radio is, there are other sites and pages that describe it in detail, no need to reinvent that wheel.

The APRS description gets into details because there are details involved in APRS. Amateur radio is not a consumer level product. One is supposed to have some knowledge and interest in radio and the modes chosen. To gain that knowledge, one usually needs to read and research.

Amateur radio is not just about buying a product off the shelf and flipping the on switch.


fyrfytr said...

Look at nwaprs.info - good information. Come to the Gathering in North Bend Wash Sept 9-12