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So how is an end fed using the coax transmission line modeled? Since the coax is two conductors, outside and inside, can the transmission line be replaced by a single wire? W8LYJ RAY

Mike, but she could support beans on that dangling feeder. -- Ron na2o

Cute: Box thinking. An End feed design for the "She Who Must Be Obeyed". A good alternative to the maligned (for good reason) EFD. Can you diagram some more; This could have legs. Lester B Veenstra

I would propose measuring with both a 49:1 and a 9:1. I'll bet the two show differing "resonances". This behavior has been documented in a previous post within this thread. Also, the seemingly "good

Here’s an idea.. coax (with an RF choke at 1/4 wavelength from end), then continue the center conductor another 1/4 wavelength. That gives you a center fed dipole (so Z is low) AND the feedline

I agree with this completely. Unfortunately my garden isn't long enough for a straight dipole and my wife (the gardener) would not tolerate the dangling feeder. -- Mike

Every ham should have a simple 1/2 wave resonate dipole for A/B testing to keep a degree of sanity. And yes, I agree this is not lab grade ( direction and angle of arrival dependent) but it does,

Just sharing some data with this group on the RF power employed when making measurements with a nanoVNA. Using a TinySA Ultra spectrum analyzer, recently I made some RF power measurements from my two

That implies a 49:1 Balun being used. However in instances of say 2800, the 49:1 leaves a 7:1 needing yet to be tuned. Much of what was in the prior thread still applies here, and I like the

Don?t compete with those, call cq yourself. 73 Peter, DJ7WW -----Original-Nachricht----- Betreff: Re: [nanovna-users] where is the end fed natural resonance Datum: 2024-02-27T09:04:48+0100 Von:

This is the EZNEC simulation of the feed point resistance of my EFHW varying with source position. -- Mike

Indeed. My main problem with talking to VK land is not the efficiency of my antenna but the pile-ups of European amateurs with kilowatt transmitters and steerable beams. The fun of the hobby is

?Ok so I meant to say UNUN or a transformer could be used. I recommend reading ARRL antenna book 25 edition, 3.2.6. Counterpoise systems. If not available look at the definition of counterpoise in

A Balun can be a transformer, but not all transformers are baluns. A balun can also be a suitable "RF choke" that prevents RF from travelling down the outside of the coax, or unbalanced currents in a

I recommend Cebik’s, “Verticals without Vertigo” I find his comments about the counterpoise enlightening. QRP Quarterly Cebik Publications ( http://on5au.be/Cebic/QRP%20Quarterly.html ) on5au.be

A balun is a device used to connect to a symmetrical fed antenna, what you mean is a transformer. 73 Peter, DJ7WW -----Original-Nachricht----- Betreff: Re: [nanovna-users] where is the end fed natural

Same. I've built a lot of antennas- My wife would say a garage full. Barring a beam, the endfed gives me great results from little work. One of the better ones I've built/used.

A BALUN is not a transformer. If impedance matching is required, from the feedpoint toward the coax feed: 1) Attached at the feedpoint of the wire: The transformer to match impedances, then 2) In

?If an antenna is fed at the end it’s an end fed regardless of length. There are 1/4 wave end fed AM broadcast and 1/2 wave end fed AM broadcast antennas. The BALUN is not part of the antenna

That sounds like confirmation bias. When conditions are good you can work the world on a wet noodle. When they are not good you need a kilowatt and an aviation hazard stack in the back yard. That's