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Which one, and why? Toroids - Baluns and Ununs.

HomerBB

Sr. Member
Jan 4, 2009
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Rogers, Ar
The question is simple, and geared to my way of thinking. I am always less interested in hieroglyphics, and more interested in what did you do and why YOU chose that one. And, of course, did it work and how well. Especially in multiband antenna use.

Making baluns and ununs isn't difficult, but for whatever little or much work it involves, some work, others don't.

So, specifically, your choices for transforming baluns (for dipoles/doublets/ OCFD) and ununs (for endfed antennas).
Also, what you like for chokes.
Please, no "ugly baluns". Toroidal builds only.
Thanks,
Homer
 
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Homer,
Several folks here say that it's overkill but I made a 1:1 choke for my 10m Inverted V. I was seeing symptoms of Common Mode and it cleared it up completely as far as I can ascertain.
I also did it because I wanted to learn how to do it. Was not difficult at all.
20220903_182034.jpg

That's a Fair-Rite FT-240-43 Mix. The wire is 14 awg Romex I had laying around.

This has some good info on chokes and toroids:

Great topic Homer!

73 sir
 
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Homer,
Several folks here say that it's overkill but I made a 1:1 choke for my 10m Inverted V. I was seeing symptoms of Common Mode and it cleared it up completely as far as I can ascertain.
I also did it because I wanted to learn how to do it. Was not difficult at all.
View attachment 63827
That's a Fair-Rite FT-240-43 Mix. The wire is 14 awg Romex I had laying around.

This has some good info on chokes and toroids:
k9yc.com/2018cookbook.pdf

73 sir
Sir Crayfish, that's a good looking homebrew choke there mi amigo.
 
The question is simple, and geared to my way of thinking. I am always less interested in hieroglyphics, and more interested in what did you do and why YOU chose that one. And, of course, did it work and how well. Especially in multiband antenna use.

Making baluns and ununs isn't difficult, but for whatever little or much work it involves, some work, others don't.

So, specifically, your choices for transforming baluns (for dipoles/doublets/ OCFD) and ununs (for endfed antennas).
Also, what you like for chokes.
Please, no "ugly baluns". Toroidal builds only.
Thanks,
Homer
Take a look at this (its all good, but about half way down is some talk on the what for and why in choosing)...
 
In the attached photos you'll see two different styled baluns, both 4:1 transformers.
I do not recall the mix of the two sleeved toroids; I built it 3 or 4 years ago to use for a low band 5:1 (it worked out being a 4:1) as the feedpoint transformer for a loop on the ground receive antenna. Conditions were bad and the experiment never got off the ground... pun intended. What I do know is it is actually a really good 4:1 starting with 20m going up through 6m.

The typical donut toroid is an FT140-61 4:1. It does a great job on 160 through 30m, but really quit transforming almost any at all to none above that range.
 

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I have made a few EFHW transformers using various sizes, all type 43 toroids. From mounted on a BNC connector to 3 x FT240-43. Also, 4:1, 9:1 tossed in along the way.
I have found 43 mix to be the most useful across the HF spectrum, but I've seen other types recommended for various uses. The T200-2 is often recommended for 9:1...
 
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Gotta catch them CMCs!
Pesky critters!

My situation here has some strong possibilities for coupling to nearby objects and causing some imbalance, so I figure the choke is in order. Doesn't seem to hurt any and seemed to reduce some issues I had beforehand.
If you find them CMC's you have to knock'em on the head.
 
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