On May 17, 2014, W1HLO launched its second high altitude balloon. The balloon was launched from our football field and required two weather balloons to lift the heavy payload. Inside the styrofoam package, an OpenTracker USB with GPS was connected to a 2M HT set to an APRS frequency (144.390MHz). George, W1GIV, configured the APRS setup. We were able to track the balloon thanks to APRS gateways and http://aprs.fi all the way to Vermont, just shy of the Canadian border. Also inside the payload was a digital video camera and CW 10m beacon that Julia, KC1AKR, built with a PIC microcontroller and a 28MHz oscillator.
You can download a kmz file of the flight for viewing in Google Earth. We lost all radio contact with the balloon as it descended close to the terrain at the landing site. The 18MHz PIC beacon was silent as well. Six months later, a hunter found our payload. He saw the contact information (a little chewed up by the mice), called us, and sent us the picture above. He said that it looked as if someone gently set the box onto the forest floor.
For future launches, we'd prefer to use a different APRS modem -- we went through a couple of the ArgentData OpenTracker USB units before we had a stable, working one. While our payload box was well insulated with 2" thick styrofoam, it was too big and heavy. Minimalism is key -- we probably would've done better with two styrofoam panels sandwiched together, hollowing out an area for the electronics. Using high altitude wind prediction software was very helpful in determining where the balloon would go on launch day. We didn't want it going into the ocean! Lastly, don't forget to file a NOTAM (NOtice To AirMen) to the FAA! We did and others in the U.S. should, too. What about that digital video camera? You can see some of its footage on our YouTube channel.