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If the nano follows the HP network analyzers, it doesn't matter what the order is until after DONE is pushed.....even if you did one of the conditions over again. Does it matter with the nano?

Ed, He is not seeing more "antenna resonances". The antenna is only resonant at 9 Mhz., 27 MHz. 45 Mhz. etc... What he is seeing is the reactance at the input of the coaxial cable become 0 at

River, I think you may want: https://github.com/ttrftech/NanoVNA/releases/tag/0.8.0 0.8.0 allows Stop Freq up to 2.7GHz. On my unit, (NanoVNA-H V3.4) it is only useful up to 2GHz or so. Up to

Ahh, antenna voltage is exactly equal to Vsum. I wrote: "Which I did not expect, let me know if I have it wrong," I was not wrong, just a little bit thick headed. Those are both real voltages

Ed, Looks to me like he really does have all those resonances at the transmitter end of his feed line. An appropriate length of feedline will turn any arbitrary impedance into a pure resistance. See

This is a correction to my first post. Unfortunately that simulation was not done in high accuracy mode so it did not correctly model the effect of ground so close to the antenna. The following

I was inspired by Jim's quick work plotting the Bessel functions, decided it was time to figure out python's matplotlib. The result is this animated GIF:

Ok. We all agree free space theoretical resonance would be something like 9.35 MHz. We also agree closer to ground would lower fundamental resonance to something lower, like 9.125 or so. But I have

Hey John, Version: 0.4.5-4-g96e7efe Build Time: Jan 18 2020 - 23:46:29

and one might want to disconnect "resonance" from "radiation efficiency" - a 10 meter long dipole (resonant at around 15 MHz) will efficiently *radiate* over a huge range of frequencies, probably

River, If you select Config/Version, what Version and Build Time is displayed? --John Gord

I recently bought the NanoVNA-H ver 3.4 and I have upgraded the firmware to the following release (https://github.com/hugen79/NanoVNA-H/releases/tag/0.4.5-4) to allow it to measure beyond 900 MHz.

Thank You very much. I am sorry that I did not mention the feeder cable originally, and I did not clarify that the antenna was not the main object but the combination of the antenna and the feeder and

Im now waiting on an eBay dealer to swap out a DOA vna-f that also had a unresponsive menu. I didnt attach it to anything and it's menu was real flakey (hit and miss). It's best to avoid the rabit

You have the impedance looking into the feedline from the transmitter end, but now you are asking what the antenna is doing. An arbitrary amount of feedline will rotate a point on the smith chart

Jim Lux, as usual, did a very credible explanation of what is going on - far better than I could! Second order differential equations are the key to understanding. I'd like to add a practical point:

Thanks for the input so far. I should have mentioned that the antenna (total length 16 meter) was connected in the middle with a 20 meter long RG58 cable. The VNA was calibrated "standalone". This was

sometimes when I go to cal, some of the selections are already reversed video, ie as if they were selected. Does this matter? Should I just go thru with cal like normal or will these odd reverse

Hi, I did go back and look at what resonance *is*. The source this time was published in 1976 but has not changed from the more ancient texts I first read (early 50s). Jim has explained things in

With all this chatter about resonance (some of which I know won't hold water) I will have to go and look again. I have been working with resonance as being when inductive reactance and capacitive