Compared: 4:1 UnUn's for Ham Radio Antennas 

This is one of the best and most comprehensive videos I have found on this subject. Thank you for all of the time and effort you put in to providing this information for us. Good job.

Very nice work! The basic rule of thumb has been that the higher perm Nickel Zinc ferrites require fewer turns to have enough reactance at the low end, so this helps at the high end. And they handle power. I don't mean to throw in another variable, but the number of turns can be adjusted based on the material.

That was a lot of work. Thanks for doing that!

Very interesting! I love that you’re doing field test bcs sometimes theory doesn’t translate to reality. Field test is really important because only then we can see how the whole irradiating system really works. 73!

On man. I’ve been waiting for this!

Great video!

Another well put together video with a stack of useful information. The results were a little disappointing because I really liked the pretty red one! 😜👍

I think I saw those on your bench during Jason's CAHRTenna build video 😉

👍Thank you sir.

A nice relaxing video for the end of the day. It amazes me that the test says one should work better but in the field says otherwise. I am wondering what the theory is behind those results?

Well done for doing these tests, a considerable amount of effort. Your S11 measurements are interesting, in many of them the resistive element is very close to 50 ohms but with a reactive element. I suspect that with a correction capacitor you could cancel some of that and raise the apparent efficiency seen in the S21 measurements. A well presented video once again, 73

nice testing. I wish I had some 240 type 52 mix to try. only have type 31 43 and 61. I did build a off set center for 10 meters veritable. used a type 61 t240 core. what i had. all speaker wire tape to DX commander 10 meter pole. got a nice tune. works about the same as T2LT coax antenna . but I did compare FT8 10 meters in the same day. just hour apart .using end fed half wave fed with 49:1 type 61 with ground plain . veritable to a off center fed 4:1 type 61 core same pole ,I have 2 . lay one down. stand outher up. what I found is my signal reports on end fed half wave was a tad better both ways . from antenna molding which i did i found half wave ground plan antenna has slight higher gain and better take off angel for dx. the off center had no ground plain. now from modeling looks like 5/8 wave ground plain get me best pattern . now I have to figure out the feed match. that 52 mix is not as common. I did find Soto beams has the T 240 type 52. I got their antenna wire in green . great wire . 73's

Looks like the best would be pairing green with one of the ferrites. Power handling improves, and both low and high bands are good. 🤔🤔🤔

I love these videos Ape. I got a question. If you have a video already that explains it feel free to point me that way. If you go from the 140-XX to a 240-XX where the XX is the same foe each, is it just bigger or is there another significant thing either good or bad?

Thanks for this. If you can, could you put your spreadsheet on google docs and share. Its would make a handy reference.

Thanks Ape. The question must have been asked before, but what would happen when you combine two different toroids and wind the wire as if they were one. Could you get the best of booth worlds like good on lower and good on higher frequencies? Or would something totally unexpected happen? I don't have any testing gear or toroids myself. So just throwing the question out there...

Generally speaking, use powdered iron for narrow frequency HF coupling, and ferrites for broadband HF and VHF applications, at least below where air-core makes more sense. Of course, core shape, size, and conductor diameter variables will also affect efficiency. Then there's power level to consider for the specific application, which will affect all of the other parameters. Then there are non-magnetic and air-cores to consider. Experimenting with transformers may be fun, but to produce optimal results it's a lot more time and energy consuming than hitting the datasheets and software transformer design applications with the requirements for your specific wants and needs, because you can do experiments with core materials forever. There are that many interactive variables. But the experiments and parameter measurements were already done 50 to 100 years ago by the core manufacturers, and the data has been put into transformer design applications. BTW, I'm not against experimentation just for the sake of experimentation. I do it all the time. It's by far my favorite aspect of ham radio. I'm a builder and experimenter, usually making do with the parts on hand and optimizing those. That's my kind of hamming. I don't own expensive ham gear or chase certificates, or rag-chew, nearly as much as I spend my time soldering and measuring, meaning precisely this sort of stuff. I'm just pointing out the best way to get an optimal solution for a specific transformer design problem is with the core data and the application software, which some hams also find to be fun.

Nice Ape! How often do you get to see the test results for the choice of a component that will go into a product. Thanks for letting us ride along Sir! 73 - KF6IF

Interesting results, most folks that I know would swear that the 43 mix would outperform the iron mix by a landslide. Would there be any reason not to use this core for an EFHW 49:1 or EFRW 9:1? Awesome video keep up the great work!

NICE! Fantastic experiment. Now it makes perfect sense why you'd use the green toroid over the traditional -43. Someday maybe I'll try an EFHW with the green one and see how that behaves, as it seems like most EFHW people are -43 junkies...73,

Very comprehensive tests, looks like 52/43/61 are all reasonable choices to make baluns given that QSB will be way worse than 0.5db. I've only used 43 for baluns. Even though they won't handle it, It might be worth seeing how long they can take 100W.

That powdered iron core are definitely going to be better at the lower freq. 73

Could you do a similar test with ATU efficiency? Like, I'm looking at getting the AH-705. Could you get two of them, tune them both at the same frequency on a random wire, then connect them back to back and test if they are more or less efficient that unun's and baluns? (the AH-705 can be connected directly to a random wire with no unun, I'm curious if it's better to use this tuner or a 9:1 unun across all parts of each band).

What is the power envelope for these QRP, 10, 20, 100W? I may have missed it in my initial watch through.

I am building a Yagi antenna would it effect the performance if I mount it on a metal pole? WQ9V

Hi ape. Thanks for the presentation. I am still not convinced with the #52 iron powder core. If it is possible, please use #26 (yellow-white, equivalentto#52)(iron powder core) along with other iron powder cores. This just satisfies my curiosity. De VU2RZA

Interesting, I thought green ones were junk. Do you plan to test ferrite rod baluns? Similar principle, but all new can of worms once you start researching it :)

OUTSTANDING! 👍 PS. I'm eating crow tonight.

👍

Where is mix 31? 🤔 👍👍👍

6:10 I'm a newer ham but I don't think these are capacitors, and if so, definitely not 100 Ohm caps. 😛

Looks good.. way to narrow it down.. testing and data rules

Money green, son.

Son, your fingers must be sore. That's a lot of cores to wrap.

Careful these torids can drive one into insanity 😂😂