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Your antenna works because the radio metal case, power cord and the shield of any accessories connected to the radio are acting as a counterpoise. You don't have a free space antenna setup. Mike N2MS

Measuring Return Loss means you are sending power to something and measuring the power returning back to the source. Then the calculation can be made. You can't calculate RL to a single wire just

I'm not building an antenna. All I want to know is if the NanoVNA can show me return loss peaks with a single length of stranded wire. Nothing more. I have an antenna and it works just fine. Don't

I have to thank you for the good advice. Even though I'm not a newbie, this was a great resource that told me where to find things. My device is the PCB-sandwich type, I downloaded edy555's build from

Or, more to the point, it _may_ radiate in some manner, because any end-fed wire will find _something_ to act as the image antenna, whether that something is intentional or not. Whether or not the

Yes, the NANOVNAs are capable of making these measurements. HOWEVER, and that's a huge "however", the chassis of the NANOVNA needs to supply the other portion of the wire. An end fed is only half the

Sure they were!? Those big taped coils in the transmitter outputs became antenna loading coils. You could say the antenna by itself wasn't resonate, but the transmitter-antenna system was. (Well,

Hi Fred How do you feed that 80m loop?? 1:1? 1:2? 1:4? Or monoband with a quarterwave 75ohm line and a 1:1 balun or current choke?? So.. I fact you can measure your loop... If you messure on a coax

Their antennas were NOT resonant! But they kept trying different things until they got their signals heard where they wanted. They learned as they went along. Just like my first lousy 80 meter

They put an amp meter between the transmitter and the antenna. Adjusted for MAX AMPS! The output circuit has lots of taps and variable caps.Could be adjusted over a wide impedance range.50 Ohms was

Real world. Interesting. If Hertz and Marconi stayed in the real world, would we have what we have now? So, if the tool we have won't work, fine. I understand that. I have seen where random lengths of

Brian, to measure the resonances of that single wire, you need to extend it straight in clear air, far from any objects, connect it to the center pin of the NanoVNA's port, and connect the shell to an

Good morning Mikki from Atlanta Ga. I have a question for you regarding the length of this wire. I have this full wave 80m loop up in the air and would like to measure it and see where the resonant

Years ago I needed to do some tests with a real TDR, so I put one together using some CMOS chips. It worked quite well despite its simplicity. It didn't care what the impedance of the transmission

Can’t you just put it up as you intend to use it and find the low points in the SWR chart, or am I forgetting something? That way it would work against the counterpoise/ground plane that you intend

Yes, it is, I did it many times and it gives me repeatable results. Simply connect the single wire into the S11 input (a cable with a PL239 socket here), I also ground the nanovna at the socket (the

You need to measure against a counter poise. Use 1 or more quarter wavelength radials connected to the ground connector shell of the nanovna. Try to replicate you operating position. Mike N2MS

Because the TDR is not really a TDR. Using frequency sweeps it does a TDR like function.But it's just a VNA doing calculations on the peaks and dips of a sweep. Just a wire by itself is NOT a 50 Ohm

The "TDR" function works - why shouldn't this? It's simple enough to test, too! -- Doug, K8RFT

Hi Brian The basic wavelength calculations would of course be your starting point.Height above ground, nearby objects, are all issues and again you really need a counterpoise to get a good