[CRAPRS] Getting in to APRS

[Jerry Pasker]

I'm new to APRS.  I last used it in 93-94, and it wasn't very mature 
back then.  I thought it was a dead technology.  A few months ago I 
got in to radio again, got my General Class, headed to HF, and very 
quickly got turned off by it.  Back to VHF I went.  Then, I heard 
digital traffic on 144.390, from multiple stations, did some 
research, was directed to Gary, NQ0V, and realized that APRS was 
alive and well in the area.  Now I'm ready to get back in to APRS 
again.  The pull of APRS is that everyone that participates, 
contributes.  And everyone that contributes more than just a local 
station (digi, or iGate) makes the system that much more useful, 
valuable, and appealing to everyone else.

And I'm diving right in.  Here's all the irons I have in the fire on 
the APRS front.  My style of doing things is to dive in, and do 
multiple projects in parallel, each in different stages, all pretty 
much at the same time.  It keeps me from getting bored on any one 
particular project.

Project 1:

I've got a Kantronics KPC3, and have found someone that will sell me 
the last updated ROM (vers 8.2) they made for the KPC3 before they 
abandoned it for the KPC3+.  I want to be able to digi the new 
WIDEn-N stuff.  It's $40 for the first one, and $20 for each 
additional one.  So if anyone needs to update an old KPC3, let me 
know.  Or if anyone has any better ideas than Kantronics version 8.2 
ROMS, let me know too.  I'll be coupling it to a radio shack 2M 
mobile that has malfunctioning front panel buttons (it's useless 
except for no-tone simplex! Perfect for packet!)   The radio+TNC will 
become first a local digi, then perhaps a local iGate.  I have other 
plans for it later.

Project 2:

A couple of OpenTrackers, and a couple of Garmin GPS LVC18s showed up 
in the mail yesterday.  I've got a couple of HTs that won't receive, 
but transmit just fine.  So I've basically got a couple of $100 
trackers to play with now.  First, I'll deploy in a vehicle, and see 
how I show up on aprs.fi.  After I'm comfortable with how I'm showing 
up, I have a solar hot air balloon that I'd like to track.  On that 
front, I still need to order a lightweight radar corner reflector for 
it and to final assembly on the payload stack and do the deep freeze 
payload endurance test on a set of 8AA lithium batteries so I know 
how long it'll transmit.  Other than that, it's ready to go.  So 
that's at least a few weeks away yet.  Probably a month. Or more. But 
that's OK, because cold weather is the hot air balloon's friend. 
I've got about 4 pounds of "lift budget" and my current payload of 
cooler, spool of fishing line, radio, batteries, tnc, gps, cables and 
antenna is 1 pound 11.2 oz.  But I think I can bring that down by 
shortening up my cable runs, using a different cooler, and soldering 
the batteries together rather than using a battery box.  The ancient 
Icom HT is of course by far the heaviest part.  I still haven't got 
the liability part of that worked out, and if I can't get it worked 
out, I'll scrub the mission.  My insurance agent seems to think it 
should fall under the same clause of my home owners insurance that a 
remote control airplane would, and would actually be covered, but 
that's not clear yet.

I would like to do the initial launch on a day where a high pressure 
system was passing overhead with low winds and winds that would 
change direction as the day went on so it would track in a smilie 
face/loop.  So I can launch, and not have to drive a million miles to 
go get it.  Then, if that's a success and everything survives, I'll 
save it all up for a day where it will get a lot of distance, and 
just not plan on chasing it.  I'll let aprs.fi do the chasing for me.

The hardest part of building and deploying a GPS tracked solar 
powered hot air balloon is figuring out the liability.  We live in a 
litigious society.  I could just use a fake call sign, and not have 
any trace of myself attached to the payload, but I would like to do 
this legally.  So I'm open to ideas/input on this.  I don't want a 
less than $200 balloon project getting me sued and bankrupt.  I'm 
pretty sure a 16 foot diameter black balloon landing on an interstate 
during sunset (solar powered, remember) would be a Bad Thing.

Project 3:

The other OpenTracker will be deployed in a remote hunting cabin, 
(off grid, solar powered) as an alarm system.  I figure I'll have it 
beacon battery voltage once an hour.  The good part is that there are 
solar panels and batteries there for the power source and I can use a 
simple door contact to have it beacon once per minute when the door 
is in an open position.... then some quick coding to parse out a text 
stream for my call letters, and a beacon message (APRS packet 
contains "KB0QCL" and "Door Open" will formulate an email to my 
phone.  Simple enough for a cabin that has a history of being 
vandalized.  I hope to have this deployed by spring.

Project 4:

This is the part where I get to contribute.

After spending way too much time on aprs.fi playing with their 
mapping, showing what nodes pick up the packets, I've concluded that 
Gary, NQ0V, is right.  There's a massive hole between Cedar Rapids 
and Dubuque.

Example:  http://aprs.fi/heard/K0QVF    Use aprs.fi/heard/ANYSTATION 
to see what that station "hears"  It shows any packets over the last 
48 hours.

http://aprs.fi/heard/K0HAM-10  Is a packet magnet!

So I've got a 150 foot tower over by Cascade that just happens to 
have a lot of things that would make this easy to do.  It has a lot 
of broadband internet to it.  It's got backup generator power.  It 
has run of 1 inch hardline from the bottom to the top that isn't 
being used.  It sits at a high elevation and has clear line of sight 
beyond highway 20 to the north.  And most importantly, I own it.  So 
a digi on that tower would be cool, but an iGate there would be even 
better.  I don't foresee myself learning to solder terminations on 1 
inch hardline and getting out to do a tower climb before spring or 
early summer of 2009.

So all these projects should all keep me busy for the next 6-12 months.


I'm open to any and all feedback on any of these projects.  Or 
assistance.  Especially if you know good ways to not be liable for 
balloons, make things be Digis/iGates or terminate 1 inch hardline.

-Jerry