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I have ECEF values that I calculated from ephemeris subframes 2/3. Using this information, I'd like to place these values on a skyplot based on my current location. I'm using a C# picture box for my skyplot image, and a custom control to show the dot and SV PRN.

I am struggling in these areas:

  1. How to merge the ECEF information with my current location to provide a useful x,y for my skyplot.
  2. How to determine the bounds of my drawing. Currently i estimate that from edge to center of my drawing is 90 pixels. So i attempted to do some scaling 90 / 20,000,000 (max distance for satellite, guessed), then multiplied that by my ECEF.x, and ECEF.y values.

I'd appreciate any help. Thanks, Jason

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