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M1 = Gunk * Gref1 M2 = Gref1 * Gref2 M3 = Gunk * Gref2 This assumes that Gunk Gref1 and Gref2 are constant during the three measurements. I do not see at all how one can fulfill this condition already

So Gunk = M1 * M3 / M2

It's also in the ARRL Antenna book. But in reality, you can build two identical reference dipoles in almost any configuration (they don't even have to be resonant or matched to 50 0 ohms) and do a

Cool! Seems to work fine here on MacOS. 73, Cliff, AE5ZA

FYI, the python based tool at https://github.com/The6P4C/dfuse-extract appears to pull perfect binary images out of the NanoVNA .dfu files found on Huygen's site (checksums the same as his .bin

Using the substitution method in measuring emissions from equipment for regulatory purposes, a dipole and a signal generator is used. There many reference dipoles out there to be had on the used

NBS (now NIST) published the dimensions of a reference dipole for such uses: 2 1λ dipoles above a 1.6λ x 2λ ground plane. Built properly it should have gain accurate to a few tenths dB or less at

Roger, Worked great. Now I have to figure out the extra menus, but that's to be expected. Thanks so much for the file. Maybe it could be uploaded to the file section of the group for others to use if

Thank you for your reply. Very interesting. Fred - N4CLA

No, Jim, absolutely no attempt to ever consider measuring the "gain" of my 450-foot doublet!!! At best, I model it using 4NEC2 and even that with a large crystal of salt. Measuring the gain

QUOTE: " Just out of curiosity, why would you want a 450 ft doublet resonant at 950 kHz?" Just to install as much wire in the air as is reasonable. I could string well over a couple thousand feet, but

You're not going to be measuring the gain of a 450 foot antenna with a NanoVNA. The OP was for a printed circuit antenna, presumably well above 100 MHz. The fundamental problem will be the free space

Hey Roger, Thanks a bunch! I'll give it a go and let you know how it went. 73, Cliff, AE5ZA

he does not want it ... but it is ;-) fed with a balanced tuner it should work any band from 160 to 10 maybe the ladderline length needs some tuning if you are at a very high or low impedance spot on

Cliff, You can covert a dfu file to bin using the DFU File Manager that comes with DfuSe demo but unfortunately that only installs on Windows. I did the conversion for you of DiSlords version 1.2 dfu

Good afternoon Dave. Just out of curiosity, why would you want a 450 ft doublet resonant at 950 kHz? Fred - N4CLA

A dipole, by definition, is resonant: +jX = -jX = 0. A doublet is a dipole, but not resonant where you require. My 450-foot doublet exhibits its first 1/2-wavelength resonance at roughly 950 kHz, but

That is the gain of a dipole antenna in free space at resonance. Over ground the gain is higher. How much higher depends on height and ground characteristics. Roger

A dipole works fine for the reference antenna. Nominally 2.2_ dB gain over isotropic. Dave - W?LEV -- Dave - W?LEV

No desire - Cube is a far better tool, and supported by ST. I see no real advantage to .dfu over .bin, and ST has obsoleted it as well.