[aprssig] Ideal Tracker Spec (Cross country on 6 AA's)

[Brad Burleson]

So I'm a real newbie here (and somewhat intimidated by the people
posting) but I have been selling a standalone lightweight APRS tracker
for HAB flights on eBay (and thru word of mouth) for about 6 months so
I thought I'd pimp myself here a bit.

My inspiration was the Byonics Micro-Trak 300... but my board uses an
AVR (the ATmega328) and is based on the Trackuino project
(http://www.trackuino.org), includes a GPS, and sells for $100.00.

The current version includes a Radiometrix HX1 (300mW) tuned to
144.390, a SkyTraq SUP500F GPS (works above 60,000'), and the AVR (aka
Arduino).  To see a picture of the current version (as well as get the
design files) check out
https://www.dropbox.com/sh/905t8qb04a83exo/akS_0Amtke?m.  Input is
always appreciated.

The unit weights 0.9oz, is 1"x3" and only needs 4xAA (run-time is
30hrs, or any DC source between 5.5-26 volts) and a 2m antenna to
function.  I've had reports that the board will run for 8hrs on 1x 9v
battery, and it once ran 12hrs on 4xAAA batteries after a payload
landed in someone's yard
(http://www.capvolunteernow.com/todays-features/?ill_units_highaltitude_balloon_project_soars_successfully&show=news&newsID=15348).

My intent here is to help people do high altitude balloon flights on
the cheap as well as improve my design/soldering skills and not so
much to make money (just check out the BOM, I'm horrible at sales and
pricing/marketing).

This board has flown 4 times beyond 60,000 feet (sadly nobody has
broken the 70k barrier yet) and one unit has been installed in an
aircraft used by the Illinois Civil Air Patrol.

Anyways I did want to add... I've got a new design that uses the ublox
MAX-6, a Sarantel SL1202 antenna and a TI TPS61202 boost converter.
To see a couple of pictures and grab the design files, take a look at
https://www.dropbox.com/sh/pw3ukfinr6e9mve/wh_THMOnoi.  This board
also runs the stock Trackuino 1.4 firmware with only 4 lines of code
changed (including callsign/comment).

I'm running tests on the prototype board with 3xAA right now
(http://aprs.fi/?c=raw&call=KF7FER-11&limit=500&view=normal).  Weight
is about the same as the previous board but with some firmware changes
I suspect running a reasonable time on 2xAA batteries is possible.

I'm pretty proud of the new design - as well as the old - and hope
this message wasn't too much of a commercial for my boards.

Regards,

Brad
KF7FER