[CRAPRS] Flew the payload!

[Jerry Pasker]

>Hello Jerry,
>
>Good to hear you're getting back out and about!
>
>Just out of curiousity, what are you using for your packet modem?

OpenTracker.  I really like it.

>The antenna I used for my payload was a 19.5" 
>piece of thin steel (similiar to a pen cap clip) 
>soldered to an SMA connector to keep the weight 
>down and make it detachable.  This was placed 
>upside down vertically under the payload.  I've 
>had good reception up to 15-20 miles away at 
>10000 feet using 300mw.

My antenna is a hunk of copper wire that i peeled 
off of a hunk of stranded copper antenna rope.  I 
picked a close length, went long, soldered it to 
a BNC connector, put it on an antenna tuner, and 
trimmed until it had a good SWR.   I hung the 
tracker package on the edge of the sport 
balloon's basket, and let the antenna wire hang 
down.  Thinking back, there would have been a 
propane tank 2 inches on the inside of the basket 
as tall as the antenna was long.  I'm sure that 
was hurting the performance.

Since I was receiving using just a portable HT 
connected to an OpenTracker2 in the chase truck 
connected to a Garmin GPS III, I was missing out 
on target course, speed, and altitude data.  I 
really need a splitter cable to utilize the 
second serial port on the OpenTracker2, just to 
get the raw packets in to a laptop..... but then 
I have to drag along a laptop.  That's a pain.

Having an aprs station that plots on a GPS map 
that fits in an ice cream bucket is wonderful. 
And in sport ballooning, small, simple, and 
portable is necessary.


>
>Just out of curiousity, what does your payload 
>weigh and how many cubic feet do you expect your 
>balloon to be to carry the payload?  I've never 
>looked in to the solar balloons much, just been 
>using latex balloons with hydrogen because it's 
>cheap and easy to get.
>

I'm doing about 3 pounds of payload with a radar 
reflector and rigging.  I don't recall the cubic 
feet of the balloon, I want to say 800+ cubic 
feet but I did do a test in the back yard, and 
was getting 5+ pounds of lift after 4pm, when the 
sun wasn't beating straight down.  I got weird 
looks from my neighbors.  I should move to the 
country.

It won't be a quick liftoff, but it should fly.