Mini UNUNs 49:1 and 9:1 (production process)

Рет қаралды 32,580

Күн бұрын

This video is about How to home made the Mini 9:1 or Mini 49:1 UNUN transformers (designed by me OM0ET). In the next video I will test them in a real conditions with the antenna wire, rope and antenna analyzer.
You can buy finished Mini UNUNs here on my website: www.om0et.com
- UNUN diagram and info: vk6ysf.com/unun_9-1.htm
#UNUN #transformer #EndFedAntenna

Пікірлер: 67

@ramonpe1ouw Жыл бұрын

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!

@WessexWeather Жыл бұрын

One of the most interesting videos you’ve produced Paul, thank you. Simon, M7WWX

@OM0ET Жыл бұрын

Thank you so much Simon for your very kind comment and support! 😊 73

@IZ0MTW Жыл бұрын

Neat construction, good building skills, attention to details. I follow you since long time and I see you always improving. Congrats! Diego

@javierpolendok5mhc 7 ай бұрын

I purchased one of these 49:1 and WOW. Couldn’t be more happier. Very resonant on all the bands . 73

@Wayde-VA3NCA Жыл бұрын

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!

@OM0ET Жыл бұрын

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! ;)

@d.j.roberts187 7 ай бұрын

Best video on this I have seen! Thanks!

@dl1hbttom703 Жыл бұрын

Very well explained, Paul ... tnx for sharing your insights 🎉

@k8ilb Жыл бұрын

Excellent video quality. Thank you.

@OM0ET Жыл бұрын

Thank you! :)

@bg7jaf Жыл бұрын

beautiful unun. nice job!

@eddyyantosjahputra9269 5 ай бұрын

Bravo my big brother in the world of RF....Thanks for the sharing

@elwood.downey Жыл бұрын

Very good. You are one of the few I've seen who get it correct that resonant efhw does not need counterpoise.

@geirha75 Жыл бұрын

What will happen if one adds the counterpoise...?

@abdulrahmanmdisa 11 ай бұрын

@@geirha75 make it flat swr on lower band

@mabo4848 Жыл бұрын

Great ! Well done

@ATOMSHAMRADIO Жыл бұрын

Cute little baluns😋

@NickkoG 10 ай бұрын

Amazing tutoriel.

@tarikhirsuva4966 Жыл бұрын

It was a very enjoyable video to watch, thank you Paul.TA2HT

@abdulrahmanmdisa 11 ай бұрын

skillfull build....make it as souvenir to ham friend

@OM0ET 11 ай бұрын

😃👍

@sleipnir242 Жыл бұрын

7351 du bon travaille merci pour le partage cordialement👍

@herberthuber409 10 ай бұрын

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,

@TerminalSump 7 ай бұрын

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 ?

@mortimersnerd801 4 ай бұрын

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?

@HamRadioPortableOperations Жыл бұрын

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

@OM0ET Жыл бұрын

Sure, an epoxy could make interior extra strong and waterproof ;)

@kampenlive Жыл бұрын

Hi OM0ET, thanks for these nice video's, question: What is the maximum transmit power for these UnUn's?

@OM0ET Жыл бұрын

I have never tested it fot it's maximum power, but I would use max.20W

@MrVertigo1971 Жыл бұрын

Great stuff. Did you use stainless steel screws for the build?

@OM0ET Жыл бұрын

Thank you. No, it's zinc protected.

@ATOMSHAMRADIO Жыл бұрын

Ununs 😋

@movecizetodobryfilm 3 ай бұрын

Hi! What brand is the soldering iron you use in the video?

@k.c.sunshine1934 4 ай бұрын

I am a novice, however, I wonder if there could be any benefit of using litz wire instead of enamelled wire in this application?

@napomania Жыл бұрын

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 :.-(

@RosssRoyce Жыл бұрын

Hi Paul, thanks for yet another nice video! Do you still sell your magnetic loop antennas?

@OM0ET Жыл бұрын

Yes of course I do. Here is my website www.om0et.com

@RosssRoyce Жыл бұрын

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

@RosssRoyce Жыл бұрын

?? Could you tell me the shipping cost to France and if your “payment methods” include PayPal please?

@OM0ET Жыл бұрын

UNUN 63€ is complete price

@RosssRoyce Жыл бұрын

@@OM0ETComplete price? Including shipping?

@geirha75 Жыл бұрын

Isn't there a short to toroid in the solder points? (37:51) I mean, the solder points are touching the toroid.

@geirha75 Жыл бұрын

@@adzbasslines268 Thank you for a great answer and 73

@LuisLopez-cv5ew 4 ай бұрын

Hi, you have the 49:1 as a kit and why you don't use a capacitor, thanks for sharing 73 WP3VU

@SeppaFrattini Жыл бұрын

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

@OM0ET Жыл бұрын

I did, but it's not in the video. Look at my website www.om0et.com/mini-49-1-unun.html 😉👍

@SeppaFrattini Жыл бұрын

@@OM0ET thank you Paul, actually I did not see. Good to know. Lookin' forward to pick you on air.

@RT65CB-SWL Жыл бұрын

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 Жыл бұрын

Yes Philip, I would recommend the 9:1 UNUN and Random wire Antenna

@RT65CB-SWL Жыл бұрын

@@OM0ET Thank you for the reply. I will order one in 2023.

Жыл бұрын

@@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. )

@RT65CB-SWL Жыл бұрын

@ Thank you for your feedback 👍

@victorb22622 Жыл бұрын

Oh,sorry,there is construction detail clip too

@sonnytee Жыл бұрын

Hi Paul, Whats the name of the soldering iron?

@OM0ET Жыл бұрын

www.gme.sk/transformatorova-pajecka-125w-etp5

@firstreponderssupplyonline7766 4 ай бұрын

I can't purchase it online, i'm from the Philippines, can you give me another option to purchase the 9:1 UNUN?

@RosssRoyce Жыл бұрын

Have you ever tried to see how the transformer behaves if the core is not ferrite but simple metal?

@OM0ET Жыл бұрын

There are versions with the iron powder toroid, but this is more a dummy load than the transformer 😊

@RosssRoyce Жыл бұрын

@@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.