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Thanks for sharing--I didn't know that either! I wonder what effect (if any) it will have on propagation here on Earth.?

73,

Mark

"A huge part of the Sun broke off of its surface and created a tornado-like
swirl around its North Pole. Though scientists are trying to analyse how
this occurred, the video of the development has stunned the space
community. The remarkable phenomenon was caught by NASA's James Webb
telescope and shared on Twitter by Dr Tamitha Skov, a space weather
forecaster, last week."

I didn't know it could do that!

--
Jed - KD0YMG -
"... we have done as much with wireless telegraphy as is likely
to be done."; Sir William Preece, 1891

I periodically search the web for good information on using a hairpin match to tune a Yagi antenna. Almost all the articles I can find are vague, stating the same advice to just fiddle with it until you get the SWR looking decent. Or, they're off at the other end of the spectrum, meaning they don't give simple, practical advice. See: http://theleggios.net/wb2hol/projects/rdf/tape_bm.htm

The "hairpin" patch is a length of wire, bent into a U shape, with the ends attached to the driven elements of the Yagi.See:

It's often more complex than it first appears, but the short answer seems to be that the hairpin match adds a shunt inductance.

The question then becomes, how does one alter the geometry of the wire to change this. Does squeezing the wire closer together add or reduce inductance? Or is it more a function of the length of the wire?

If the latter, then it would seem the best approach is to build something similar to the adjustable hairpin match sold by DX Engineering.

Hi everyone,

As you may know, I'm giving a talk on SOTA/POTA/QRP operating at our April 1 club meeting, and I'm wondering if there are others in the club that have done a bit of SOTA/POTA. If yes, I'd love to include some stories from other SOTA fans. Please feel free to either post a message here or you can drop me an email to k0ehr at arrl dot net. Thanks in advance!