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Pete, I've modeled with 4NEC2 an end-fed wire with various source impedances and counterpoise lengths. The 2450 ohm source impedance seems close to optimum. You have to choose some step-up ratio. Once

Welcome to the forum, Brent. There are several guides in the files section, including the Absolute Beginners Guide.? Go through the forum's Wiki for additional information. There are also many

I think that is one of the reasons the transformer should ideally be measured as a full 2 port device using a full two port VNA. This can also be done with a TR VNA like the nanovna with a little

Interesting article, thanks! I think the best way to measure/model the transformer is to take a proper full two port model using the nanovna. This is a bit fiddly to do with a TR VNA but worth the

I just noticed a getting started guide under the files section. Reading thru it now.

Hello. I just received my H4 and I'm finding it difficult to understand the main website and getting this device to function properly. I'm try to just start with something basic like SWR over 30-40

Gary Have you considered what the feed point impedance of an EFHW is against the equivalent source impedance the 1:49 transformer has created? Is there a reasonable conjugate match? I have measured

Hello, I regularly use the Zplots.xls https://ac6la.com/zplots1.html Download: https://ac6la.com/Zplots.zip , I have used it a lot with my antenna analyser SARK100, it is very versatile and useful,

Hi Dave, Yes, the winding is tapped as an autotransformer and not a bifilar separate primary. I didn't think it would make much difference. But after seeing a couple of comments, I measured things

Got it. ??? Mikek -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Would you please take multiple pictures out of the box so we can see the winding technique and how things are connected! It appears the secondary is center tapped. Please - out of the bos! Dave - W

Gary - very interesting! I would urge you to also post notice of your work on QRZ.com. There is active discussion of EFHW 49:1 technology in the "Antennas, Feedlines, Towers & Rotors" forum, with

You don't need a cal without the cable. Essentially, calibrating at the end of your test cable makes the cable "part of the instrument"

Ya, I have not looked it over real well, but it does give signal strength, S/N and IF-AGC %. ?Also the station frequency, and physical channel. The signal strength indicator is under, Product

Yep, I have had my Sony TV for 10 years and never saw the signal meter, I finally found it a week ago. Yesterday, I went to pull it up and had do go through the whole search again. it's not clearly

Hi Bryon, If you look further down to the "core size" experiments you will see that I did indeed test 2 FT240-43 cores with 2:14 turns. It is a reasonable choice, and with the large volume and surface

I have made a 50 to 75 ohm adapter for the connectors I need. I used the insulation and center conductor inside the F connector and butted the SMA? panel mount connector center pin and RG6 center pin

I probably wasn't clear, my TV has a good signal strength meter in it, I just wanted more fun trying to measure the impedance.

Ok, but I can't do both, the cal is which ever one I do last. Yes, there are memories, but then which cal means what? Mikek > > > > > -- This email has been checked for viruses by Avast antivirus

OK, this looks easy, I already put a 75 ohm termination on the coax, but I''l go back and calibrate with the 75ohm at the NanoVna output.