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I am going to be working with wire antennas in the 3 to 30 MHz range. I would like to attach the VNA at the antenna feed point and have the antenna at operating height. Therefore I would like to use

Polyethylene and PTFE (Teflon) are notorious for being not-sticky and paint won't stick. So they make primers that purport to either give a "tooth" to the surface or that make the surface otherwise

What is “self-etching primer”?

A thin coat of conductive paint over a coat of self etching primer will take care of any and all ESD issues. I use it a lot when installing RF assemblies into cheap plastic project boxes. The

How can I put nanovna Saver into Debug mode? John

You could be missing the correct Microsoft Visual C++ package Here are the links: This is for the VNA Saver software page and it mentions the issue further down

S parameters get used in matrix calculations on arbitrarily complex networks, they have to be mathematically correct. The "Return Loss" in dB, on the other hand, strikes me as a handy way to casually

The book is available (legally) on the web as a pdf: http://www.w3pga.org/Antenna%20Books/Reflections%20III.pdf Maxwell had an amazing career, and knew this stuff cold. Lots of good insights in that

Clarifying it seems unlikely to appreciably mitigate Wiki confusion...

Thanks.

https://store.cq-amateur-radio.com/shop/reflections-iii/

Which Maxwell? What book? DaveD

This reminds me of this old discussion about how to represent the reflection coefficient. The stuff included below is from post /g/nanovna-users/topic/34589622#5275 All but the final

I cheated and used 1/4" (5.6mm) plywood as its easy to cut and finish plus wooden legs. Allison ----------------- No direct email, it goes to bit bucket due address harvesting in groups.IO

Thank you for the article Roger. So many people doing it incorrectly is no excuse to remain ignorant. We can start here and now, since it is pertinent to this purpose of this group. Danny K5CG

It is incorrect but so many people do it even in engineering literature. The editor of IEEE transactions got concerned about it and wrote this article... Roger

And generally they're both plotted with "smaller reflection coefficient magnitude lower than higher" - So the plot goes from, say, -40 to 0 (or 40 to 0)

You will see Return Loss presented both ways, depending on the author. Retaining the negative sign is less often seen and perhaps *wrong*, but either way the intent is obvious. Jerry, KE7ER

Larry, I assume the user guide you wanted me to look at is this one: /g/nanovna-users/files/NanoVNA-User-Guide-English-reformat-Jan-15-20.pdf I tried using an earlier version of that

The presentation is very good. However, slide 12 is not correct in the suggestion that Return Loss is always a negative number. That is simply not the case. The reflection magnitude in db is always a