DM09 - 2019-06-03

Tracker Details

Tracker Type: WSPR

Model: PicoTrackerWSPR1 Rev5 0.6mm thickness

Powered by 2 AAA batteries


19:46:51.597288, Parameters: (set <param> <val>)
19:46:51.629846, trackerId[4]            : DM09
19:46:51.658143, wsprCallsignId[2]       : Q2
19:46:51.706759, gpsLockTimeoutMs        : 150000 2:30
19:46:51.739303, lhAltFtThreshold        : 10000
19:46:51.787816, hAlt.wakeAndEvaluateMs  : 600000 10:00
19:46:51.831034, lAlt.wakeAndEvaluateMs  : 45000 45
19:46:51.879702, lAlt.stickyMs           : 86400000 24:00:00
19:46:51.912117, crystalCorrectionFactor : 1300
19:46:51.944594, systemClockOffsetMs     : 9

Launch Parameters

Balloon and Payload

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

Heat sealed neck.


  • random WSPR channel selection
  • reduced weight, keeping free lift the same (3g), what happens to altitude
  • box launcher

Weight saving approaches:

  • Thin board (0.6)
  • Cut off headers
  • Thin antenna (magnet wire)



Could see a few of my signals from after launch.

Next day mid-day balloon was spotted again.

It was descending, and only was spotted at 10,000ft. Why? It was well into daylight.

General Thoughts / Observations

Basically windless. Ideal.

Tracker was tangled up like crazy when arrived in the park.

Head lamp was critical.

The wires are just fucking too much.

Balloon did not shoot up despite the calculated 3g free lift.

Perhaps to do with my adding extra tape every foot up the top antenna/ribbon.

I also hadn't accounted for the extra stability tape for top/bottom antennas.

Something wrong with software? Why only seeing signals again starting at 10,000ft?

Need to look into this more, as this happens to be the low/high altitude threshold.

Also, why did it crash?

Perhaps it was so light that the 3g free lift was excessive and balloon popped?

What is a good value?

Adjust weight to take into consideration extra tape for bottom/top antenna, as well as sealing top antenna to ribbon.

Figure something out about tracker getting tangled/flipped around with wires.

Ideally part of this is joining top antenna and ribbon somehow.

Transport in a way that doesn't lead to tangles.

Velcro water bottles to base?

Leave tracker somewhere where antenna not at risk of snag?

Maybe remove clip completely?

Tether balloon how?

Use 30m so nighttime transmits work? Possible to alternate between frequencies with single antenna?

Reduce free lift to avoid pop at altitude?

Change low/high altitude to 15,000 just to spot if there's some kind of bug at the 10,000ft mark.