Thank you for this comment. Been trying to wrap my head around this for a couple days now. You just made it clear.

@@smokeweedeveryday9099 Glad you got it! I'm really confused now!😀

Many thanks Sean, finding time for the hobby is difficult at this time.

Well and your videos are technically more substantial than a bloody random review of whatever gear some one sent someone to review( Pander) or doing unboxing's lol. Baby's want milk, men want meat , you got lot meat on the bone information and skill wise and I for one appreciate that time you take . Can't tell you how much I have learned last couple years watching you and Calums's videos, and a few good laughs thanks again and keep doing what you do !

Many thanks 🍌🍌

Thanks

Yes next video, what is better a 64:1 or a 64:1 or a 49:1.???

Yes a very good point Joe, thanks 😊

The 3 turns make an inductor, in series with the source impedance (typically 50 ohms). Reactance = inductance × frequencies × 2 × pi. When reactance equals impedance, you have reached a -3dB cut-off point. A high pass filter. Having 3 turns instead of 2 gives higher inductance, the unun is more efficient at lower frequencies. 80 metre band, maybe even 160 metre.

​@@Soupie62i lost you at the very end, so are you saying that 2 turn is preffered for lower bands(80m) and 3 primary turns is more efficient for higher band like 40m and up? Thanks

@@Mark300win Generally, inductance is proportional to N^2 (square of the number of turns). If a single turn has inductance X, 2-turns will be 4X, and 3-turns will be 9X. 9/4 = 2.25, so a 3-turn coil will be about 2.25 the inductance of a 2-turn coil. If a 2-turn coil is 1 uH (micro Henry), its reactance at 3.5MHz (80m band) is about 22 ohms. In series with a 50 ohm source, coil signal is about -5dB. A 3-turn versiion is 2.25x this, or 2.25 uH. Reactance st 3.5MHz is about 49 ohms. Coils signal is now about -3dB. Conclusion: more turns is better for low frequencies. Maximum useable frequency is a different topic, where the core material in the transformer becomes significant.

@@Soupie62 awesome! Thank you

You'll likely need more toroids for 1500W. Once you saturate the toroids your SWR will go nuts. And they'll get very hot.

Hi Don, good to hear from you, yep there is a gasket so water tight 🤔🍌🍌

I have the same question. I’ve seen the bifilar windings considered primary only, followed by secondary windings with single wire to complete the ratio of bifilar/ primary : single/secondary. I hope someone answers this.

Thank you

I have not worked out the fine details yet on the LED's, 9:1 for a random length of wire (non resident on any of the HAM frequencies) --- 49:1 halfwave length 80M - 10M. ---- 64:1 = halfwave length 160M to 40M

Cheers Andy. 👍

How do you determine the wattage one of these will work with and how do you go about creating one for a higher power transmitter? Thanks 73

Many thanks..

43mix 240 size

You are probably right.

eBay

Well that’s a go question, the short answer is that they both work well. A 49:1 transforms from 2450 Ohms down to 50 Ohms and the 64:1 from 3200 Ohms to 50 Ohms both the 2450 and the 3200 ohms are present at the end of a length of wire depending on the length of counter poise and radiating wire and ground conditions. I choose the 64:1 as I have found that it is the most suitable for me having built both.

Yes I remember them, glowing on top of my car antenna…😂

That is a good point, sometimes I do however with a clear case I can see if I need to add one later or not.

eBay and 240/43 mix.. :)

I have returned to the simple 2 + 14 as there was no real benefit to the 3 + 21 so the classic wins....

@@mike-M0MSNif going to the 64:1 unun is not worth it, why not share that as a pinned comment so others don’t waste time in a futile project?

Also, if you can find a reamer like what you would use to prep copper pipe, the kind with the swivel tip, they work fantastic on plastics like PVC, to clean up drilled holes.

According to Eland Cables, 1.83 mm diameter is 13 AWG. 73

Cheers Chaps..

Exactly my thoughts.

Yep I tend to have stuff lying around and then build from it....

Cheers

He did say the size of the wire - 1.8mm or approx 14 AWG. The size of the bolts doesn't really matter just so long as they're at least as big as the wire.

I do like the idea of the coffee plug in…😂

I can’t find a table of the different measurement standards for wires, can you provide a link to your given data?

Searching eBay as we speak for some…

This video builder shows the video in his playlist. Which one is better? 64:1 or 49:1 and he shows a print out screenshot of his findings on the SWR on at different frequencies. In my personal opinion, based on that and what he did 2 turn 2 core. 49:1 seems to fit the bill across the board

Yep experimental

@@mike-M0MSN I built a 64:1 over the weekend, was great on 40m but not great on 20 15 or 10. I also tried different capacitor values from 100 to 300 pF. In the end I converted it to a 49:1. Best results were without the capacitor.

It depends on the impedance of the antenna you're trying to match. If it is closer to 2450 ohms you use the 49:1. If it is closer to 3200 ohms you use the 64:1. If you don't have any way of measuring the antenna impedance you use the one that works better :)

⁠@@stargazer7644I’m totally new to this, what are you referring to 2450Ω or 3200Ω and how do I find out what I have?

@@azarellediaz4892 It is the impedance of the antenna you're trying to match your 50 ohm radio to. Just try both and use the one that gives the best SWR.

Both will work, voltage or current is the difference..

I guess it depends on the length of wire. but 64:1 may be better??

Thanks for your Reply to my UNUN Problem 49:1 or 64:1 I don't think is the Problem in my case.. The length of the (Long wire) would be better if I could have a longer run.. However I have maxed out the length restrictions of my property.. so perhaps a new style / type of antenna would be required for the lower frequency.. (Tunable Loop antenna) is what I am considering to Rcv 30 khz to 500 khz.. then for frequencies (above 25 MHz) just use my Discone antenna for that, and above... 73s@@stargazer7644

@@x_CrossHair_x Just keep in mind that discone antennas work equally poorly across a large range of frequencies. Band specific antenna perform far better. 30-500 khz requires very special antennas because resonance at the freqs require truly huge antennas - so all practical antennas are low efficiency at those freqs.

Thanks again for your input.. and band specific is my dilemma.. So.. I'm working on it. With hopes of constructing a Tunable (Box Frame Loop) if that is a good enough visual description.. Not sure if you can call it a Magnetic loop.. but close to that. in appearance. (Long main loop / with an induction loop. tuned with a old school open air Adjustable Capacitor.. in the picofarad tuning Range).. all I can do is cross my fingers that when built.. Will Work 🤞🤞.@@stargazer7644

Is the ratio 7x7 49 8x8 64

Yes, both transformers will have an impedance RATIO of 64:1, but the actual measured impedance of the primary on a 16:2 and a 24:3 will be different. You want the coax side to be close to 50 ohms for a good match with the transmitter. Ideally you want 50:3200 ohms, not 25:1600 ohms (as an example) at the design frequency even though both of these are 64:1.

Yes, however I’m unsure of the key down time as heat is a factor…

Yes you van do that.

You can use stranded wire, but it has more loss at RF and will get hotter.

in the UK, everything is QRP

internal?? use google! 1.5mm = 15 gauge

Thanks for the tip Jim.

All baluns are transformers, but not all transformers are baluns. The difference is how they're wound. A proper 4:1 balun (for example) actually has two devices in it - a 4:1 transformer, and a 1:1 balun. TRXLab did a wonderful series on how they work and how to make them: kzfaq.info/get/bejne/obOcfsl5rbicdo0.html

@@stargazer7644 Thanks… and I really liked his German accent. I think I should leave this clever stuff to others and just buy my things from the retailers… but thanks for your advice. I’m watching more of the posts… it’ll probably fuse my brains though. 🤪

Sad you have that terrible condition and can’t enjoy tinkering any longer. This means now you can spend the time teaching the new generation of upcoming Hams.