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Jupiter-T timing receiver oddness

MS
Mark Sims
Tue, Jun 7, 2016 4:19 PM

I added support for the Jupiter-T receiver to Lady Heather and noticed something odd.  On the sat position/signal level map sat PRN 9 was always being drawn with a small black circle in the middle.  I could not figure out what was causing this... until I noticed that sat PRN 27 (which was visible, but untracked due to low signal level) was being reported as being at the same az/el as PRN 9.  The black dot was PRN 27's location/signal level being overlaid on PRN 9's
Analyzing some logged data, it looks like something about PRN27 confuses the Jupiter-T  Other receivers showed PRN27 in its proper position with a strong signal.  Doing a factory reset on the receiver (which flushes the almanac, ephemeris, etc) did not change anything.

I added support for the Jupiter-T receiver to Lady Heather and noticed something odd. On the sat position/signal level map sat PRN 9 was always being drawn with a small black circle in the middle. I could not figure out what was causing this... until I noticed that sat PRN 27 (which was visible, but untracked due to low signal level) was being reported as being at the same az/el as PRN 9. The black dot was PRN 27's location/signal level being overlaid on PRN 9's Analyzing some logged data, it looks like something about PRN27 confuses the Jupiter-T Other receivers showed PRN27 in its proper position with a strong signal. Doing a factory reset on the receiver (which flushes the almanac, ephemeris, etc) did not change anything.