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I live in a quiet neighbourhood; the antenna measures 8 cm from tip to tip. I shall take some measurements at the countryside and report back when I do.

Too bad it doesn't lead to any practical use. What do you expect me to do with a deadly formula like this? -- F1AMM Fran?ois

I was thinking that such fluctuations seen in NanoVNA were due to swinging of my multi-band fan dipole in the wind! That would change the relative nearness of elements to each other and nearby

Or to put it simply, the VNA contains a highly specialized radio receiver. "W0LEV via groups.io" <davearea51a@...> wrote: -- 73 -Jim NU0C

Nothing.. just some places block accesses to various countries, so finding alternate ways to get there is useful. There was a time when .int was resolved through a DNS server in China, which is

If you have a close-by strong source of RF energy like FM or AM broadcasters, police, ambulance, CB'ers, hams, ....... any of those and more could be affecting the readings. This is not all that

Is it normal for the readings to fluctuate as much as 2-3 ohms ? As in 11+/-1.5 - j(70+/-1.5) Dipole NMHA (antenna), balun, calibrated, two ferrites: one at the balun and one at the VNA S11 port. No

No, but a guy may have already worked DXCC while you're still arguing about whether an antenna is good or not. Get on and use it. Play with it later as needed. Zack

Yes. Alan is one of the "big boys" and belongs to Tek. Those by amateurs and others may be highly questionable. At least those are my experiences with YouToob. For example, addressing ferrites,

Even a linear wire, not coiled, has some measurable inductance. At zero length the display on the Smith chart, will show a single value of zero at the extreme left of the real axis. That point on

You can absolutely trust Alan Wolke W2AEW's videos. He is a Tektronix Field Engineer, I know him personally and knows his stuff 100%. https://www.youtube.com/results?search_query=w2aew+nanoVNA And,

Dave, One doubt about the Smith Chart: Why does the so-called resistive component change as you move across the tracing? If it was the true electrical resistance due to the ohmic resistance of the

That being said, the aim of a radio amateur is to have a QSO, without damaging equipment and causing interference (RFI)! All these - balun, common mode choke, SWR meter and NanoVNA, are aids

Possibly the attachment will help. Dave - W?LEV [email protected]> wrote:

Beware of most YouToob presentations. Those by the "big boys" which offer their instruments for lots of $$$$ are good and solid. Many of those by amateurs or "self proclaimed experts" are flawed.

QUOTE: However a successful QSO is not scientific evidence of a "good" or "bad" antenna. If it works, great. But do not use this as evidence of optimum antenna performance:-) ** I'd also

All info here is accurate. BUT, to save time, calculate the "electrical" wavelength needed mathematically for the "rough" estimate. Wavelength = 300/frequency (MHz) multiplied by the specified

When I started in ham radio, 46 years ago, indeed almost nobody used baluns with dipole antennas. Nowadays instead it's very common to use them, and there are at least two good reasons for this

Thanks a lot Inviato da iPad

If the video on Youtube notes that the impedance should be zero, it is incorrect. The THRU impedance should be 50 ohms. I just checked on three NanoVNA's, and they all measure 50 ohms. Zack