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Roger, I will look at the model with the SD card connector. I don't mind having to file the case. The plastic case is lighter than the other analyzers which is an asset when hiking. The case corners

Yes, I biffed it yesterday in initially quoting εr. I entered the published velocity factor of 0.91 instead. My error. However, the effective εr can be derived from Vp as: εr = [1/ SQRT(Vp)]. So,

i have encountered a situation when i bricked, oh crap, oh $hit, kaput or whatever u call it when the device no longer works as expected and tried to reflash and the programmer said it verified ok but

That's why I bought a -F, after trying my early -H outdoors many times. Or make a "viewing hood" out of black cloth. -- Doug, K8RFT

The ARRL Ant Book-supplied program TLW, has most of the "450 ohm line" at about 405. Don't know how you applied the Nanovna but for impedances above a few hundred ohms S11 accuracy falls apart. I have

Dave, Why should that calculator be correct? Second, why not measure the Zo with the nano? in combo with the 1/8 lambda trick or 1/4 lambda + SmithChart trick? 73 Arie PA3A Op 25-2-2021 om 23:58

Bricked to me means irrevocably broken, not wrong firmware or user bootloader installed. It is very difficult to do short of supplying overvoltage or physically damaging. Installing the wrong firmware

Manfred - Thank you! That post is very helpful, Now I have a chance at (re-) sorting my cores. I can now go from E, rod, broken, conductive (iron), and non-conductive (ferite) piles to something a

David, After reading your post I was sure I had read somewhere about windowed ladder line not being the advertised 450 ohms. I dug around a little and found this post from years past....

Why an εr of 0.91 ?? Air is 1.00054. When I put your wire spacing (21.6mm) and conductor diameter 1.29 mm) in I get the following for air 420 ohms. What is the εr of windowed ladderline that is

Yes, it is, Jim. We're not dealing with metamaterials!! Too many things going on in my 74 YO gray matter. With a measured Vp of 0.87, the effective εr should be 1.07. Dave - WLEV

Yes, much better calculator. Yes, I biffed it a bit on εr. Wireman gives Vp = 0.91. I measure 0.87 which yields an εr of 1.07. But given my measurements of L and C for 7.17 feet, I still see more

I always get a kick out of it when someone mentions SimSmith. The Sim Smith Bridge in Indiana was built in 1883. (OK, I'm in a weird mood today.) :-) Zack W9SZ wrote:

It is quite a feat to get a relative epsilon less than 1 <grin> You can do it with ionized plasmas, but I suspect that's n

Mike: 100kHz steps is pretty coarse resolution, some bands might only have 1 to 3 points with lots of wasted points between ham bands; you might want to take narrower sweeps of the bands you plan to

I was doing some modeling using SimSmith and measured values of the shack end of my 450-foot long doublet fed with (mostly) 450-ohm window line. I was not getting what I would expect, so I measured

It took pretty much my entire morning. But I have to admit that my morning started around 11 AM! ;-)

You get 2 out of 3 with the NanoVNA-H4. With the latest software you get 401 points and there is an SD card storage capability. On mine you have to file the case slot to access the SD card connector

I am preparing for portable operations once the weather gets warmer. I want to take along a nanovna to troubleshoot issues on the field. One important requirement is the scrolling and input control

Look like broken LCD module (or bad connection). Blue LED flash - mean normal scan, as i see your device worked, and can send data to CPU over USB. Problem in LCD module (or in SPI bus), try check it