Sunday, 2 August 2015

Balloon Experiment Crosses York Region

Toronto Ham David Beverstein, VE3KCL, Launched a balloon experiment consisting of 2 foil balloons filled with Hydrogen with a payload of WSPR, JT9 and CW telemetry beacons from a bit Southwest of the intersection of Airport Road and Highway 89. The track across our region runs more or less along King Road from King City to Gormley although the precision of the track is limited to that of a 6 character grid square due to bandwidth limitations in the WSPR protocol and a low duty cycle of 12 minutes per beacon to conserve power. At the time of writing it is over the North Atlantic about 1/2 way to Europe at about the latitude of Kentucky and has reached an altitude of almost 8000 metres.

This "mission" page gives more details on the project, the telemetry and the progress of the mission, or check out the full size map.

The main source of telemetry is the WSPR protocol. There are a large number of receiving stations for WSPR which makes it ideal (other than the low bandwidth) for very weak beacons. These receiving stations relay the information received to the WSPR Network web site where anyone can see them on the map. The site will automatically take you to the 30m reports which is the band used by this mission. If you don't see it try extending the time period to greater than 10 minutes. You may see the report come from a strange place, like I did when I saw it over the Southern tip of India. I think this is because of some of the additional telemetry (like battery condition and altitude) that is overlaid on the grid locator field in the WSPR protocol (there is a full description of how this works on the mission page, including the link to the raw WSPR decodes from the balloon's transmitter. If you go to the links in the previous paragraph the extended protocol is properly decoded and the map will show the correct position.

In the last 12 hours (at time of writing) it has been picked up by 10 stations in North America and 1 in New Zealand. A quick review of the raw telemetry data shows that 64 stations have picked up the balloon so far, including VA3ROM and VA3XCD in Thunder Bay and Yarker (about 30km NW of Kingston) Ontario respectively. A large number of reports have been made by VE1VDM, who has an advantage by being further East than most of North America.

The mission site reports that the JT9 transmissions have been received. However the PSKReporter network does not report any transmissions received at the time of writing. There are far fewer receiving stations on PSKreporter 30m JT9 than on WSPR and probably more importantly WSPR can operate on a lower signal to noise ratio.

Anyway if you're up for it set yourself up for WSPR and see if you can receive its transmissions while it's still in the air.

Chris VE3NRT

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