What a nice coincidence, watching this video while turning the dial on the 20m band and finding you calling CQ. That doesn't happen every day! Very nice and tidy build indeed. Keep on doing the good stuff, Paul!
Hallo OM Paul. Tnx fer this great video. I wanted to build these two transformers myself. The main problem is to get coloured wires 😄. Again, many thanks
Hi Paul, very neat build! I've made some very similar to that 9:1, but without the CP terminal, rather I built a second 1:1 choke balun which I connect on the end of the feed line such that the counter poise is the sheild of the feed line on the antenna side and RF is choked off from the radio side. The "balun inside plastic tubing" is such a nice compact and versatile format for portable! I'm currently making one with an AM broadcast interference filter in it to protect from front end overload when operating my x6100 within range of a strong broadcaster... Love your channel and thanks for your content!
Thank you so much! :) Advantage of to have an extra terminal for a counterpoise is that you can choose if you want to have an extra wire or to use the feedline as a counterpoise ;) Congrats to your own similar project! ;)
Paul... have you ever measured the efficiency of those 49:1 UNUN's? If not, take two of em, tie em together, put a measured 10 watts on various bands (into a wattmeter) then 10 watts through the 2 tied together baluns (they should be able to handle that) measure the power you get at the wattmeter then double it...(you really want to measure the loss of just 1 balun) Tell us what you get?
Hi Paul, great video, thank you. maybe this has already been asked but I don’t know. In the 9:1, is there a problem that the solder joints made at 37:51 on the toroid are touching the toroid or even touching each other as it moves in my rucksack ? Does this cause a problem ?
@@OM0ETno, I mean solid iron, no plates, no powder. And I don’t mean mental speculation but “have you tried”. I’d try it myself but I don’t have all of your testing equipment to discern the unit behavior.
Super compact, very nice! Would be great for backpack portable. Great work. Would you advised against using an epoxy resin for potting or would there be no real advantage? Also would be great to see an RF 1:1 common mode choke version. 👍73
Thanks! I’d buy you one if you could ship it to France for 15€ and if you accept PayPal. The site said “see shipping cost on form” but I didn’t find it there. Nice site by the way, just as you creations - very neat and well organized! Cheers
so the differences between 49/9/4:1 is the total lenght of the cables over the toroid? still don't catcht it even if i 'm reading a book about it but is a too complex book with so much formulas :.-(
Very nice work. There's a question about the 49:1 unun, they say it would be better putting an high voltage 100-150pF capacitor at the feed input in order to flat the swr response on higher bands, worth it? Any reason you didn't? Thank you, 73 ivE3iaa
Hi Paul [OM0ET] would you recommend an UNUN for use with a random/long wire antenna and a short-wave radio receiver? If "Yes!" which one? My short-wave receivers are a Yausu FRG-7 and a Realistic DX-440 with a random length wire and 'Slinky' and some wire in my attic/loft space. 73's Philip [RT65CB/SWL]
@@OM0ET Thank you for the reply. I will order one in 2023.
ปีที่แล้ว +1
@@RT65CB-SWL I have one of his 9:1 unun´s and it works well with my 30 m wire and 7 m counterpoise. Use it to my airspy sdr radio. (Had to modify it with a another winding on the coax side to make it isolated from the antenna and earth windings. My laptop psu is the culprit with very high noise leves below the 49 m band. The end of the antenna and laptop is not far away for the moment. I hope you don´t mind for modifying it Paul :-) Nice and small unun and perfect for rx use. )
What a nice coincidence, watching this video while turning the dial on the 20m band and finding you calling CQ. That doesn't happen every day! Very nice and tidy build indeed. Keep on doing the good stuff, Paul!
These are really beautiful! I like the enclosed design -- should be very robust for rough and tumble field deployments.
Hallo OM Paul. Tnx fer this great video. I wanted to build these two transformers myself. The main problem is to get coloured wires 😄. Again, many thanks
I purchased one of these 49:1 and WOW. Couldn’t be more happier. Very resonant on all the bands . 73
Hi Paul, very neat build! I've made some very similar to that 9:1, but without the CP terminal, rather I built a second 1:1 choke balun which I connect on the end of the feed line such that the counter poise is the sheild of the feed line on the antenna side and RF is choked off from the radio side.
The "balun inside plastic tubing" is such a nice compact and versatile format for portable! I'm currently making one with an AM broadcast interference filter in it to protect from front end overload when operating my x6100 within range of a strong broadcaster...
Love your channel and thanks for your content!
Thank you so much! :) Advantage of to have an extra terminal for a counterpoise is that you can choose if you want to have an extra wire or to use the feedline as a counterpoise ;) Congrats to your own similar project! ;)
Bravo my big brother in the world of RF....Thanks for the sharing
Very good. You are one of the few I've seen who get it correct that resonant efhw does not need counterpoise.
What will happen if one adds the counterpoise...?
@@geirha75 make it flat swr on lower band
Neat construction, good building skills, attention to details. I follow you since long time and I see you always improving. Congrats!
Diego
Paul... have you ever measured the efficiency of those 49:1 UNUN's? If not, take two of em, tie em together, put a measured 10 watts on various bands (into a wattmeter) then 10 watts through the 2 tied together baluns (they should be able to handle that) measure the power you get at the wattmeter then double it...(you really want to measure the loss of just 1 balun) Tell us what you get?
Cute little baluns😋
Excellent video quality. Thank you.
Thank you! :)
Very well explained, Paul ... tnx for sharing your insights 🎉
thanks for providing information. in your diagram unun 9:1 there are 10 windings
. I presume it's 9 windings like in your desingn.
Hi, you have the 49:1 as a kit and why you don't use a capacitor, thanks for sharing 73 WP3VU
It was a very enjoyable video to watch, thank you Paul.TA2HT
beautiful unun. nice job!
skillfull build....make it as souvenir to ham friend
😃👍
Amazing tutoriel.
What is the soldering iron you are using, it looks really nice. I will be making these Unun's soon. Thank you for the great video.
Great ! Well done
I am a novice, however, I wonder if there could be any benefit of using litz wire instead of enamelled wire in this application?
Hello Paul, thank you very much for your informative posts and videos, do you also sell such products or where can you buy them, have a nice day,
I can't purchase it online, i'm from the Philippines, can you give me another option to purchase the 9:1 UNUN?
Hi Paul, great video, thank you. maybe this has already been asked but I don’t know. In the 9:1, is there a problem that the solder joints made at 37:51 on the toroid are touching the toroid or even touching each other as it moves in my rucksack ? Does this cause a problem ?
Have you ever tried to see how the transformer behaves if the core is not ferrite but simple metal?
There are versions with the iron powder toroid, but this is more a dummy load than the transformer 😊
@@OM0ETno, I mean solid iron, no plates, no powder. And I don’t mean mental speculation but “have you tried”. I’d try it myself but I don’t have all of your testing equipment to discern the unit behavior.
You didn't show video ,how you made balun
Oh,sorry,there is construction detail clip too
Super compact, very nice! Would be great for backpack portable. Great work. Would you advised against using an epoxy resin for potting or would there be no real advantage? Also would be great to see an RF 1:1 common mode choke version. 👍73
Sure, an epoxy could make interior extra strong and waterproof ;)
Hi Paul, Whats the name of the soldering iron?
www.gme.sk/transformatorova-pajecka-125w-etp5
Ununs 😋
I hope that all the bolts and nuts are stainless steel.
Hi Paul, thanks for yet another nice video! Do you still sell your magnetic loop antennas?
Yes of course I do. Here is my website www.om0et.com
Thanks! I’d buy you one if you could ship it to France for 15€ and if you accept PayPal. The site said “see shipping cost on form” but I didn’t find it there. Nice site by the way, just as you creations - very neat and well organized! Cheers
?? Could you tell me the shipping cost to France and if your “payment methods” include PayPal please?
UNUN 63€ is complete price
@@OM0ETComplete price? Including shipping?
Too many ads, wont watch any more, greedy
Use brave browser
Hi! What brand is the soldering iron you use in the video?
Hi OM0ET, thanks for these nice video's, question: What is the maximum transmit power for these UnUn's?
I have never tested it fot it's maximum power, but I would use max.20W
73!
One of the most interesting videos you’ve produced Paul, thank you. Simon, M7WWX
Thank you so much Simon for your very kind comment and support! 😊 73
so the differences between 49/9/4:1 is the total lenght of the cables over the toroid? still don't catcht it even if i 'm reading a book about it but is a too complex book with so much formulas :.-(
7351 du bon travaille merci pour le partage cordialement👍
Best video on this I have seen! Thanks!
Very nice work. There's a question about the 49:1 unun, they say it would be better putting an high voltage 100-150pF capacitor at the feed input in order to flat the swr response on higher bands, worth it? Any reason you didn't? Thank you, 73 ivE3iaa
I did, but it's not in the video. Look at my website www.om0et.com/mini-49-1-unun.html 😉👍
@@OM0ET thank you Paul, actually I did not see. Good to know. Lookin' forward to pick you on air.
Great stuff. Did you use stainless steel screws for the build?
Thank you. No, it's zinc protected.
Hi Paul [OM0ET] would you recommend an UNUN for use with a random/long wire antenna and a short-wave radio receiver? If "Yes!" which one?
My short-wave receivers are a Yausu FRG-7 and a Realistic DX-440 with a random length wire and 'Slinky' and some wire in my attic/loft space.
73's Philip [RT65CB/SWL]
Yes Philip, I would recommend the 9:1 UNUN and Random wire Antenna
@@OM0ET Thank you for the reply. I will order one in 2023.
@@RT65CB-SWL I have one of his 9:1 unun´s and it works well with my 30 m wire and 7 m counterpoise. Use it to my airspy sdr radio.
(Had to modify it with a another winding on the coax side to make it isolated from the antenna and earth windings. My laptop psu is the culprit with very high noise leves below the 49 m band. The end of the antenna and laptop is not far away for the moment. I hope you don´t mind for modifying it Paul :-) Nice and small unun and perfect for rx use. )
@ Thank you for your feedback 👍