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Learning KML camera views with Ham Radio and Project TouCans

 This is so cool! I had a discussion a few nights back about what time of day Project TouCans had been spotted in New Zealand on 20 meters—the few times that its signal had reached out that far. We have a Datasette <add link> database of al the rigs QSOs and RBN spots, so it was simple enough to look up the answer. A few minutes after I started, I had a Google Earth Pro map of—kml file—of all the spots. Using the 'Show Sunlight' feature of app, I quickly realized that all of the spots had been at or near grey line.

Here's the thing though, I wanted to animate how the sun's position on the horizon changed with each QSO, but... Every time I clicked on a new QSO, Google Earth Pro 'helpfully' moved the maps view camera to center the rather large QSO path on the map from space. Not. Helpful.

<Add gif here>

And this is where the kml concept of camera saved the day! I was able to add a camera tag to the kml file that pointed the map's camera at the exact same specified view of the horizon for every QSO. (Datasette's ability to fill in Jinja templates made trial and error to get this just so super easy.) Here's the tag I used. (The code can be seen here.)


You can see the results below. The video opens with a view of the McLaren Park water tower to help orient viewers, (at least viewer's from San Francisco.) The fixed camera tag then brings us to the view specified by the tag above. I was able to  make a video of the sun first rising further to the South as time moved deeper into the Winter, and then rising further to the North after the new year and the onset of Spring! Check it out!

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