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I've looked online, and can find very little information on using an microSD card with this device. Can anyone who actually owns an H4 device let me know of any information they gathered (any links

Not sure that's true, but I have to admit, that's the part of SWR theory that I struggle the most If you check formula for reflection coefficient ( R = (Z1-Z2)/(Z1+Z2) ) and any random "online

This is the best video I've found on the subject. It took a lot of searching, as there is a lot of trash out there! https://youtu.be/NTC5FWVvLcI

An antenna does not have to be resonant to radiate efficiently. It will radiate all of the power that is applied to it, less any resistive losses in the antenna. What is important is getting the power

If that is the situation then there WILL be standing waves on the line! The fact that the impedance is transformed at the end of the line to 50ohms does not alter what happens on the line at the

thank you. Interesting to find that my antenna tuner likes the 80m band better (not by a lot) than the 40. What is interesting is how quiet they both are. NVIS being this close to the ground (an

is the h4 a sa or vna?.

Good point..... I made a measurement of a 2M dipole constructed from some brass rod and suspended about 5 feet of the workshop floor. The NanoVNA-H4 was connected directly at the feedpoint. The

If one measures SWR in the shack considering the antenna plus feedline (assumed coax) as a system, there is a good way to verify there is no standing waves or reflections on the line - A totally

“If your "generator is Z1=R+jX, for VSWR to be 1:1 the load must be Z2=R+jX (R=R and X=X, if not obvious otherwise)” Correction - the load impedance must be the complex conjugate of the

A simple answer - for VSWR 1:1, X must be 0 and R must be 50. In any other case you will have "impedance mismatch", that will causes "reflection", and reflection "causes" VSWR A bit longer

Yes the lengths are wrong but the DX Engineering one is even more off John ve3ips So 34 ft for 40 and 70 for 80m then tune for resonance John ve3ips

Well, can anyone come up with a case where the VSWR measures at 1:1 and the Smith chart is not on the zero reactance line. And in fact for 1:1 you would have to be dead center, based on analysis

Hello David, The 40M leg is too long. The SWR and RL are rising with the increase in frequency. The 80M leg is too short. The SWR and RL are improving with the increase in frequency. HTH...Bob

William, As mentioned our local radio club has a copy, but I'm not there for a few weeks. Stan Dye already answered my question, but will still read the book when I'm next at the club. I've the

Maybe, I have more than one complaint, the screen seems insensitive especially when I'm trying to program frequency, those numbers just don't want to respond. Other times the sensitivity is fine

Your unit might not be broken, in the conventional sense! Read in this group about adjusting the display. The display on the nanoVNA is resistive, and many times issues can be corrected by adjusting

Hey, I wired up a 118' X 68' crossed dipole antenna per the recipe here https://w8jxn.org/?p=1650. I was able to get very good transmission 5x9 to a collaborator some miles away on 3.915MHz. The 40M

I borrowed a friends NanoVNA, same model, same reputable seller. The borrowed unit works like my unit never worked. It was always a bit difficult to get the screen to respond. I wish I had known how

Any of the NANOVNAs are well suited to make your desired measurements: SWR and R ± j X. Minimum or 1:1 SWR is not a good indicator of resonance, regardless of ham "lore" and misinformation. The