Copasetic Flow

 I spent a little bit of time doing math debug this weekend, but in the end it turned out the QSO mapping app had a visualization issue, not a math issue. It was fun to get to look at the math for calculating the apparent launch angle of our antenna using F2 height data and rx/tx station locations. I wouldn't have thought to do the review except I had data that didn't match the maps I was getting back. According to the launch ange calculations made by our, (mine and KO6BTY's), QSO mapping app, the launch angle for the signal from our QTH was 0.00227 degrees. The map however, showed the path of the signal soaring over the very nearby Bay Bridge. The angle shown is much larger than 0.00227 degrees. Here's a picture of the nearby Bay Bridge with our antenna in the foreground. After completely reviewing the underlying math, it occurred to me that CZML likes to make lines that follow great circles. To make something that approximated a circle out of a path with a very low ...

 On one of the most interesting radio days of our recent camping trip, Project TouCans made QSOs with Australia, Japan, Columbia, and Argentina, all on the same day! The QSOs to Japan and Australia were made in the middle of their night. The Japan, Australia, and Columbia QSOs were all made in a sixteen minute window beginning with VK3YV at 12:40 UTC. What was the Propagation Mode? While the QSOs were awesome! How did they happen? I did a bit of research.  Spoiler: I don't have an answer yet. If you have ideas, I'd love help on this, please comment! Dayside stations talking to nightside stations led me to sv1uy's page on chordal hop propagation which had a nice diagram The rest of the notes from below followed from this diagram. I don't have answers yet, but here are my notes. I've been talking with the kids about radio occultation, refraction, and of course, the Gladych research project during all of this. I'm also using it to introduce trig which will layer i...

 We got to camp a bit more in the middle of nowhere than we usually do while traveling across Utah last weekend. My partner found the Burr Trail Scenic Byway. I've looked for a route across southern Utah for the last several years, but had somehow missed this really nice, well-paved, little road. We camped at the foot of an East-facing cliff, and the QSO map for the POTA reflected that fact pretty nicely: Based on this overall map, I didn't think we could hit the West Coast because of this cliff face. Almost all of the QSOs and spots paid attention to that cliff face. And then, there was N0OI: How? How had the signal cleared the cliff and skipped out to Perris, CA? Using data from the Boulder, CO ionosonde , at the time Project TouCans was spotted in California, the F2 layer skip is modeled in the gif below. Note that it clears the mesa, (just barely.) The other skip off to the Southeast was headed to the Cayman Islands. All of the skewing around is to convince myself that the ...