Thanks for the detail SR 👍

@@TheSmokinApe you are welcome ape De VU2RZA

Lol, thanks Bob 👍

Thanks for checking it out Chuck 👍

Glad you enjoyed it!

Thanks HRC 👍

Thanks for checking it out Dennis 👍

Thanks James, glad you liked it 👍

Thanks KS0JD, glad you liked it 👍

Thanks for checking it out 👍

lol, thanks Andy 👍

Thanks for checking it out David 👍

Awe shucks, thanks Lee 👍

Good luck with it, I am sure you will figure something out!

@@TheSmokinApe🤔

I wouldn’t put much credence into it, son. While I’m sure you are a wizard with the maths, I believe these measurements were taken with the janky leads….

Sorry, I’m not experienced enough with smps to answer

It does matter but to a less extent as the main reason for larger cores is heat dissipation which is less of a problem in chokes.

The number of windings does make a difference but when you get about ~11 the impact is greatly reduced. The magnetic properties of the core is the magic in a choke which is missing in an air wound choke, the work but need to be accurately tuned, which is difficult, and are very narrow in bandwidth making them limited for effective use. You can measure then with a VNA.

I’d say that’s getting there, I’d definitely want less than a dB

The orientation of the wraps isn’t that important. If it tests out OK, use it and see how you do. Thanks for watching TB 👍

@@TheSmokinApe Thanks Ape!

#43ferrite (ui=850) is Ni-Zn and #31 is Mn-Zn (ui=>1000) ferrites. Any ferrite being ferromagnetic, can be used as a transformer or as a CMC choke for a particular frequency range. #73,75,77 are all Mn-Zn ferrites with ui=>2000 or more and can be used as transformer cores for the lower most end of the HF and the MW frequency band; they can very well be used as CMC chokes too. De VU2RZA

Hey oob, I typically use 31 for broad band chokes. That said this particular core FT114-43 is commonly used by dipole antenna manufacturers which is why I was testing it in the first place. That said, I felt it was an adequate example for this demonstration. Thanks for the comment!

@@TheSmokinApe you are right, ape. De VU2RZA

I've tried all sorts for chokes and transformers even junk from hamfests which ultimately end on power cords. Yes, there is some cross-pollination between the various types but as each type has its unique specs, they also act as either a choke or a transformer in different parts of the spectrum, hence the different types. Were they completely interchangeable there'd be no need for the various types. This past Hamvention I attended a presentation Friday evening at a dinner where this very topic was discussed and led by Bob Brehm, AK6R, Chief Engineer of Palomar Engineers. He has a plethora of information on their site including the above presentation. I was able to speak with him separately about this and broader "core" topics. The nice thing about Palomar Engineers is you can buy a complete unit or you can buy whatever parts you need and roll your own. I've bought cores from eBay and Amazon but never sure if the item is what it's advertised as. Buying from Bob I never have to worry. I have bought complete units and parts to make my own. I'm very pleased with the products and tech support he provides. I'd rather source my information and parts from a reputable company. I also consider the "Ape" a reputable source. That's why I subscribe to his channel.

@@oobihdahboobeeboppah Thanks for the details and for the vote of confidence 👍

Hi, the buddy stick pro is essentially an unbalanced vertical antenna with a counterpoise (elevated ground radial) You are using the UnUn to curtail the CMC that tries to disconnect the USB when you operate FT8 mode. A bifillar wound or a coaxial cable wound cmc choke can be used as a BalUn or UnUn depending upon where you put it. When placed at the feed point of a center fed 1/2 lambda dipole it is called a BalUn; ie, looking from the antenna side, and the dipole being a balanced device. From the coaxial cable (an inherently unbalanced device) it may be called an UnBal, though the terminology is not in vogue. A UnUn is a device connecting two Unbalanced ports together on either side. The impedance transformation achieved can be simply a 1:1 or other ratio as well. The bifillar wound or coaxial cable wound choke when used on a coaxial cable feeder before it enters the shack end of the coaxial cable it is called a UnUn (because both coaxial cables are Unbalanced devices) A UnUn can be used at the feed point of OCF dipole (Windom etc) , the slimjim, J pole and the EFHWA etc. So, the UnUn, what you are using is correct in your buddy stick pro antenna. De VU2RZA

@@subramanianr7206 thank you!

I think they are handy, I always use chokes with transformers. Thanks for the comment 👍

Thanks for the heads up Trent

If you have an antenna with a Balun or a Choke you do not need a second one at the feedpoint. Both Baluns and chokes balance current and reduce CMC and both terms are used interchangeably for both devices, often you will hear the term "balun choke". There are a few ways to make both, so pick a design you like and try it, measure with a nanoVNA and pick what works best for your situation. Hope that helps 👍

@TheSmokinApe It does, and I have a Nano on the way, once it arrives (yet another learning curve), I'll investigate. I'm getting what I believe to be interference from either my antenna and/or my feed line turning on a couple of "capacitive touch" lamps and the garage door opener lights in my house. That doesn't bother me except for whatever affect I'm having on my neighbors, so I'm trying to clean up radiation.

An air core Balun or ugly (not exactly though) BalUn is not broadbanded and might vary well become a wave trap for a particular frequency band with the right amount of inductive and capacitive reactance. Ferrite loaded BalUn can be compact and offer the right amount of resistivity for the CMC that tends to flow on the outer side of the coaxial cable shield. I believe, by flowerpot antenna, you mean for the 2 meter band and you can very well use 2-3 turns of the coaxial cable feeder on the 1" long #61 ferrite cylinder sleeve core. And the 2 meter band calls for 144-148 mhz only and hence an air core ugly BalUn will serve the purpose well. De VU2RZA

@@subramanianr7206 Thanks I have an 2m flowerpot already. Was planing a 10m (28mhz) one and it calls for 4.3 metres of coax air choke. The lower section is ~2.5m of coax to mid point where the centre coax then joins to the ~2.5m wire going up for the upper section. So from input to the choke to the actual mid point real feed point is already 6.8m of rg58. Then I have the coax run back to the rig which could be rg213. Just trying to cut down the coax loss in the 4.3 meters in the air choke

@@moozoowizard hi, that is fine. A flowerpot antenna (for the 10 meter band, 2.5 meter on either side) is, for convenience and polarization, essentially a center fed dipole in vertical orientation. For this band, 4.3 meter RG58 coaxial cable wound as an ugly BalUn is the easiest way and its bandwidth is adequate. A CMC choke wound on a #52 (ui=250) or #61(ui=125) ferrite core (either a torus or a sleeve cylinder) to bring about an impedance of 500 ohms or more is warranted here. Use the formula 2pifL to calculate the reactance in ohms. Instead of RG58, you can use RG316, Teflon coaxial cable for a much smaller bending radius; it is good to handle more than 100 watts. De VU2RZA

@@subramanianr7206 Thanks. Very Good info 👍. I'll do that. VK6MIK

@@moozoowizard thanks and you are welcome 👍 De VU2RZA

You damn right! Thanks for watching Mike 👍

That’s the next one 👍

Haha, thanks Don

Yep, that's always a good idea 👍

I am sure that will work to some extent but the magnetic properties of ferrite are greater. Thank for the comment Manual.

Hi, maybe you are joking, or mistaken. Ferrites are iron oxide plus other metal elements containing ceramic materials interspersed with nonconducting glue material, synthesized as in the pottery making for specific magnetic properties and purposes. Steel or soft iron are good for DC and low frequency AC. De VU2RZA