Best 4:1 UnUn for Ham Radio Antennas?

[@patthesoundguy]

Whats super fun about this video is I'm in the middle of my ham course and I recently learned a bit of this theory so I'm able to follow along better than I would have before.

[@TheSmokinApe]

Awesome Pat, thanks for watching 👍

[@don_n5skt]

Thanks Ape. I really never think through this. I have seen it written but then they show the formula and don't work through it. Videos like this are very helpful.

[@TheSmokinApe]

Thanks Don, that’s why I’m here 🤨

[@MikeN2MAK]

Very cool. I appreciate all the testing you did for the new 4:1 antenna and can't wait to try it out!

[@TheSmokinApe]

Hey Mike, we liked the testing. Now we just need to get them shipped 👀

[@KK6USYHamRadioAdventures]

I wonder how that would work for an antenna

[@TheSmokinApe]

Me too!

[@BarefootBeekeeper]

Your explanations are models of clarity. Thank you.

[@TheSmokinApe]

Thanks BBB, glad you like them 👍

[@dan_in_sd]

Ape, isnt that the toroid that will be on the new CaHR vertical antenna? ;)

[@TheSmokinApe]

It is...

[@acestudioscouk-Ace-G0ACE]

Does the 52 mix give a better frequency response at lower frequencies than the 43 please?

[@TheSmokinApe]

It depends on the application but many folks use the ferrite mix 52 for 80 and 160 👍

[@maurasmith-mitsky762]

Thanks!

[@TheSmokinApe]

Thanks 👍

[@betmulligan6192]

As soon as you said "square root" my eyes glazed over. I kept following your math, though, and understood what you did. Good going and thank you.

[@TheSmokinApe]

Thanks for watching 👍

[@VE9ASN]

I use 4:1 with a 1:1 choke directly below it for 160m and 80m loops, its a great setup. I wish we could attach pics here, id show the rig expert screenshot.

[@TheSmokinApe]

Hey less, it is a good idea to use the 1:1, thanks for the comment 👍

[@de_w8tam]

What mix is that toroid? Thanks Ape!

[@TheSmokinApe]

52 Powder Iron

[@MIKROWAVE1]

Transmission line transformers are quite forgiving as to core material compared to conventional transformers or autotransformers. My advice - test them as conventional transformers (Primary -secondary maybe 10T each, or conventional Autotransformer) at POWER. This helps to sort out the mystery core material performance better than return loss alone... The 52 Mix is supposedly Powdered Iron according to Micrometals and NiZn ferrite material according to Fair-rite, with a perm of 75 to 250. Data sheets are all over the place on values. Dunno how these are equal. They are supposed to be lower loss at higher frequencies than the Yellow White Type 26 typically found in ATX Power Supplies.

[@TheSmokinApe]

These are type 52 powdered iron and not the mix 52 ferrites, I think you are recognizing that. We, along with others have used these is a 25’ vertical antenna configuration with four 17’ ground radials with success from 40-10m. I don’t recall anyone trying on 6m. We did use a tuner but with that antenna configuration it’s to be expected. Admittedly, I was surprised at the results.

[@Cliff-KI5OPP]

So thats the one for the new verticle then?

[@TheSmokinApe]

This is for the new Poseidon CaHRtenna 👍

[@dougdaniels]

Very good explanation. Most of the antenna kits tell you the power limit on the build. Is that determined by any of these calculations, or is it solely dependent on the size of the toroid (tow-roid)?

[@Ezzell_]

I believe the gauge of the wire is the biggest criteria.

[@TheSmokinApe]

Hey Doug, the size and composition of the core are the two most critical factors. When these cores get hot they loss magnetic properties which stops their ability to transform impedance. More power = more heat.

[@robertmeyer4744]

looks good. nice core mix to go up to 6 meters. I have wrapped a t 240-61 at 4:1 Balun . for off set center fed veritable for 10/11/12 meters. 1/2 wave total and feed point at 1/3 from bottom. making around 200 ohm feed impedance . will go up DX commander pole . will be a mono band type. have all the parts but not put together. I used 14 AWG mag wire. this type does not need ground plain or counter poise. it is a balanced dipole. it is when we feed at end it goes unbalanced and counter poise of some type. that need UNUN to feed. my antenna go bag is getting bigger. and still a easy carry for POTA . mat do a 2 or 3 stack 4:1 with T 240 for 1Kw . lord Callum can do 1 KW now. off com license change . 1 KW for the UK. now 100 watt stations came back to me /QRP . was funny. several did it to me on 10 meters in the AM . FTDX 10 sounds great from England 100 watts on 10 meters. 73's

[@TheSmokinApe]

Hey Robert! This is for a vertical ground plane type antenna, the CaHRtenna Poseidon

[@robertmeyer4744]

@@TheSmokinApe I was thinking that. love the test video's that dropped lately . with the cores back to back. put 50 ohm dummy load on it and you can do power test for core heating.

[@TheSmokinApe]

I actually have a video like that planned 👍

[@subramanianr7206]

Hi Robert, let me make some clarifications. An OCF, off-center fed dipole is an unbalanced antenna. You are using a half lambda wire and feed it in the center because the feed point impedance is low in the range of 50-75 ohms and is suitable for a coaxial cable. This center fed dipole is resonant (on only one frequency) and can be used for a single band only. If you want to work on multiple bands, you have to find out a point on the half lambda wire that would remain with a fairly fixed impedance. It can be 1/3rd or 1/4th from any one extreme end of the half lambda wire; it would be around 200-300 ohms depending on other factors especially like the feed point height above the ground. So, a 4 to1 or 6 to1 transformation to the standard 50 ohm coaxial cable is needed. Here, in this video Ape demonstrates a 4 to 1 Ruthrof voltage BalUn. The demerit of this design (apart from the choice of wrong core mix) is that it won't provide any CMC, common mode current suppression. Yes, in any OCF, you will be expecting the CMC problem. You can mitigate in two ways. 1. The Ruthrof voltage BalUn must be followed by a 1 to 1 CMC choke. 2. You can go for a 4 to 1 Guenella current BalUn using two ferrite cores of sufficient size for the power to be handled. Don't get tempted to use a single core 4 to 1 BalUn. Just for completion: ferrite cores are termed like FT82-61. Iron powder cores are termed like T200-2. When you intend to use more than 600w, you should go for Teflon wires of sufficient gauge; don't use enameled copper wire (magnet wire) I think this helps. De VU2RZA

[@robertmeyer4744]

@@subramanianr7206 what I made was a mono band off center fed. only for 10,11,12 meters buy folding extra wire and wrapping it around. adjusting match. not a high power antenna. just one FT 240-61 core I had. and my coax feed has choke at end wear it goes to Balun. everything made with Walmart speaker wire . just testing. I got tune on CB CH 20 at 1.2 VSWR . just speaker wire and tape. all tape on DX commander 10 meter pole. hears the skip like crazy. I will use better wire next time. I did do a 2 stack wound 10 AWG 49:1 and handles 1 KW tested . 400 watt FT8 hours cores slay slightly warm . no rise in SWR . I have thermal imaging camera . Flair . 73's

[@bassangler73]

Very important! Thanks Ape

[@TheSmokinApe]

I try! Thanks BA 👍

[@ScatManAust]

G'day APE Now using this specific setup, you got close enough as you say. My question is, supposing using this core can you modify the type of wire and spacing fine tune and get the theoretical 1-1? I'm also guessing slightly altering the number of turns would throw things way off from the desired effect. I know it would not be worth doing this, but I'm guessing you could.

[@TheSmokinApe]

You could. But you would need to know the impedance of the antenna and then adjust accordingly 👍

[@danazlin3409]

So, how did you determine how many turns to use on that particular core? An d why did you choose that particular core? 😀

[@TheSmokinApe]

Here’s how we picked the core, we also did other tests. Compared: 4:1 UnUn's for Ham Radio Antennas kzbin.info/www/bejne/oorLimZ-qs9qpq8 Also, we did similar for the number of windings.

[@gregwmanning]

What type of resistors did you use? Did you choose low inductance resistor or are ordinary resistors ok to use at HF freqs?

[@TheSmokinApe]

Carbon file low inductance, ordinary will add reactance 👍

[@subramanianr7206]

Hi, ape. I'm glad that you made a 4:1 Ruthrof voltage BalUn and tested it. The only thing that bothers me is that you used the wrong core material. Iron powder core #52 is equivalent to #26, which is meant for power transformers and high current chokes in switching power supplies. De VU2RZA

[@TheSmokinApe]

Hey Subramanian. Thanks for the post, I did read the spec sheet but for this particular build we did test a few different Toroids and much to my surprise this one did particularly well.

[@subramanianr7206]

@TheSmokinApe OK Ape. Thanks for responding. But this core can be used in MW frequencies; it can be used as high as 1 MHz or 1.5 MHz max. That's all. You may get deceived sometimes with the nanoVNA. In the real world, it would be useless. Instead, you can test mix 2 or mix 6. I believe you might have tested them already 🤔 De VU2RZA

[@MrStanwyck]

What is the part number for the Toroid you used for the 4:1 unun? I’d like to make a 4:1.

[@TheSmokinApe]

It’s a Micrometals T130-53

[@RyanJennings-m5d]

Thanks for a nice technical video.

[@TheSmokinApe]

Thanks for watching 👍

[@danazlin3409]

I hear a lot about dual core 4:1 Guanella current baluns and how to make them, but I can't seem to find any practical examples of how to make a dual core 4:1 Guanelle Unun. Maybe you could address that one in a video? Supposedly, the dual core 4:1 Guanella unun is more efficient than the single core 4:1 unun you built in this video.

[@TheSmokinApe]

I think there is much debate over the dual Guanella vs the Ruthoff and Guanella current hybrid. I can do a video, at some point on the dual Guanella

[@WECB640]

Hi Ape. What mix are you using for the toroid? Looks blue/green to me, but the closest colors I can find are blue/yellow which would be a type 17 (roughly half of the Al of a type 2). Thanks and 73.

[@TheSmokinApe]

Hey Hollywood, I just emailed over the specs...

[@Ezzell_]

I have listen to many youtubers talking about Ununs and Blauns and say they dont know why a balun is called a balun. I have never some one say this...but it strikes me that if an unun is an unbalanced to a unbalances ..then could they the bal in balun be for "balanced" because it it is a balanced to an unbalanced device.

[@K4AX]

Yup, balun=Balanced to unbalanced connection.

[@TheSmokinApe]

K4AX is correct.

[@HOAHamRadio]

Hmmmm, I see a vertical in my future 🙂

[@TheSmokinApe]

That might be true

[@mostlypostie1]

This at 200 ohms would probably work pretty well for a deltaloop too.

[@TheSmokinApe]

Yeah, not a bad idea

[@NickFrom1228]

This is a question for everyone. I've seen videos of people warning about the quality of toroids. I can't find the main video I recall that gave good sources. So, does anyone recomendations of good sources for toroids. I need to build a cmc choke and then a balan or two. Many thanks.

[@mikesradiorepair]

Electronic parts distributors like DigiKey, Mouser, Newark, etc.... If your looking for ones specifically for amateur radio related uses then Palomar Engineers is a good source of known good quality cores.

[@TheSmokinApe]

JPMSupply.com is good 👍

[@NickFrom1228]

@@TheSmokinApe I appreciate that. I'll check them out.

[@Frank_K4FMH]

Jim Henson is from Leland, MS, just NW of me. He’d be proud, Ape. You’ve made being Green much easier! 😂

[@TheSmokinApe]

Haha, it’s not easy!

[@geirha75]

are there efhw antennas with 200R impedance?

[@TheSmokinApe]

It's not for a EFHW, its for a short vertical ground plane.

[@KS0JD]

What's the mix on the toe-roid? 73

[@TheSmokinApe]

52 👍

[@jomckarth4836]

great, tks

[@TheSmokinApe]

Thanks for watching 👍

[@KF0NNQ]

Cool and thanks. I had never scene the math. Love the math and theory of hamming. 73, KF0NNQ.

[@TheSmokinApe]

Glad you liked it Bill 👍

[@ornithopterindia]

👍Thank you sir.

[@TheSmokinApe]

Thanks

[@hamradioexperience]

what are those green/blue toroids? I pulled a pair of them out of some scrap electronics the other day and was wondering. Interesting that they're making an appearance here... (apparently, I'm the 73rd comment, so) 73,

[@TheSmokinApe]

They are t130 type 52 powered iron 👍

[@hamradioexperience]

@@TheSmokinApegiven that, I'm blown away that they work as well as they do at HF!

[@TheSmokinApe]

@@hamradioexperience I was a little surprised myself

[@hamradioexperience]

@@TheSmokinApeI'll have to do some more testing. I was literally just told they MAY be of LIMITED use on HF. They seemed great from your video. Other than at sub-80m. I might try to duplicate your results, then copy with a -43 mix. Might be interesting...

[@TheSmokinApe]

@@hamradioexperience I’d be interested to hear what you find. We did compare them to multiple core and then decided to go with this one. Thanks for watching HRE 👍

[@DonzLockz]

Hmmm, what is the symbol for "squirt" in your calculations son?😂 Will there be toe-roid mix options for different frequency requirements?

[@TheSmokinApe]

Not sure about the symbol. Just one roid for 40-6 👍

[@temporarilyoffline]

Its faster because its green also.

[@Ezzell_]

Your avatar looks weird without a hat....

[@temporarilyoffline]

@@Ezzell_ it does, but I can't remember where I made it to update it.

[@temporarilyoffline]

@@Ezzell_ it does, but I can't remember where I made it to update it.

[@TheSmokinApe]

Green = more faster