DM11 - 2019-07-14

Tracker Details

Tracker Type: WSPR

Model: PicoTrackerWSPR1 Rev5 0.6mm thickness

Powered by 2 AAA batteries


Parameters: (set <param> <val>)
trackerId[4]            : DM11
wsprCallsignId[2]       : Q2
gpsLockTimeoutMs        : 150000 2:30
lhAltFtThreshold        : 19000
hAlt.wakeAndEvaluateMs  : 1200000 20:00
lAlt.wakeAndEvaluateMs  : 180000 3:00
lAlt.stickyMs           : 43200000 12:00:00
crystalCorrectionFactor : 1050
systemClockOffsetMs     : -4

Altitude cutoff higher because I expect high float, would want to know if it was coming down earlier.

Sticky and high/low alt intervals calculate out to ~7-8 days.

Launch Parameters

Balloon and Payload

  • 36" Qualatex, unstretched
  • 21.8 gram payload
  • 2.1 grams free lift
  • Half-wave antenna.

Heat sealed neck.



Popped about 1/3 across the atlantic after hanging out at 27k for a while.

General Thoughts / Observations

Did a parking lot launch outside the building.

Gusty and fairly windy, but wanted to try it anyway.

Waited for dead moments and let it go.

I let it go 3 times before my final let-go.

Each of those times I didn't like where the balloon was going and reeled it back in by the top antenna, which seemed fine.

A visual inspection after the first or second showed no loosening of the attach point to the balloon.

Actually went pretty well.

The gusty wind outside was a pain but my water bottles and step-by-step launch approach worked through it all.

So, no change to launch procedure necessary.

Try two balloons to get higher above weather effects.

Secondary benefit is perhaps less stress on any one balloon, but who knows by how much.