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Bob wrote: My end-fed half-wave is the off-center-fed-dipole concept taken to the extreme. Works great, in my opinion. But it's difficult to get the matching network right, especially if shooting for

On 8/12/20 2:37 PM, David Eckhardt wrote: > Not quite correct! Ladder line is a transmission line just like coaxial > line. However, they perform their function differently. > 1) The center fed dipole

Or have a relay box at the far end (Antenna Under Test) with open, short, load, antenna. At HF, the distance through the box is negligible. However, there are cases where you don't want "wires" near

I used to use tuners.? No more.? I cut my antennas so that they are in resonance or close.? If I want to operate too far from that frequency I might use a tuner for just that although the

Darrell: ? I initially make a wire antenna a little longer than the formula calls for(it's easier to cut than to add wire).? Put up without the autotuner.? Check with the nanovna or an SWR

Thanks. From what I have read, I am going to try 135’. The builder of the matchbox says to stay away from 1/2 wave or its multiples. Thanks Darrell Sent from my over-rated IPhone 7 Plus. Any

I will lookup how to use NanoSaver. Thanks Darrell Sent from my over-rated IPhone 7 Plus. Any Mis-spellings or grammar errors are due to my IPhone auto correct feature.

Thank you. Excuse my beginner questions but it seems I have a lot to learn. I will be using a auto tuner. I was just trying to find out what my SWR would be on the different bands and where it would

Dave is right about this: Many hams do simple tie their 50 or 75 ohm coax directly into the center-fed dipole. Often that works just fine, so OK to just flip something up and try the baluns and chokes

You are most concerned with the impedance the end of the coax presents to your matching network/radio. Therefore, you should measure at the shack end of the coax. Calibrate the VNA as a stand-alone

As far as a counterpoise goes: As a single-ended, common mode source/load, the fields must go somewhere. They don't just abruptly stop at the feed of the EFHW (end fed half wave). Yes, the coaxial

It is my understanding that this Matchbox is a 9:1. The system gets good reviews on 80-10m. So if I am using this system, would I need to calibrate the NanoVNA using the coax, then get my measurements

Not quite correct! Ladder line is a transmission line just like coaxial line. However, they perform their function differently. 1) The center fed dipole is a balanced source/load - differential

I am slowly getting parts in to try my end fed long wire antenna. Correct me if I am wrong. With a center fed dipole, the 300 or 450 ohm ladder line feeding it is part of the antenna. I would think I

This doesn't answer your question, but I believe you could achieve the same result by calibrating the VNA through your run of coax to the antenna feed point. So perhaps have an assistant up on the

I am going to be working with wire antennas in the 3 to 30 MHz range. I would like to attach the VNA at the antenna feed point and have the antenna at operating height. Therefore I would like to use

Polyethylene and PTFE (Teflon) are notorious for being not-sticky and paint won't stick. So they make primers that purport to either give a "tooth" to the surface or that make the surface otherwise

What is “self-etching primer”?

A thin coat of conductive paint over a coat of self etching primer will take care of any and all ESD issues. I use it a lot when installing RF assemblies into cheap plastic project boxes. The

How can I put nanovna Saver into Debug mode? John