Building a 9:1 UNUN With FT-140-43 Toroid.

Подписаться 43 тыс.

Просмотров 41 тыс.

50% 1

Building a 9:1 UNUN for a random-wire multi-band end-fed antenna using an FT-140-43 toroid instead of the usual T106-2. Presumably the ferrite toroid works better for the lower bands, 40 and 80m, and as well for the upper bands, I would guess up to 10m, not sure about 6m. It remains to be tested in an upcoming video. I should have measured SWR with a 470-Ohm resistor between ground and antenna wire but I forgot. A random wire by the way is any wire which is not a half-wave of any band to be used. The 9:1 UNUN usually requires a tuner.
End-fed antennas: • Clearing Up Some Confu...
EARCHI UNUN: www.earchi.org/92011endfedfile...
The field test link will be here as soon as completed.
Help this channel: / radioprepper DISCLAIMER: The Radio Prepper logo (depicting a microphone) is indeed inspired from a famous flag created in 1775. It is NOTHING BUT a symbol of freedom and independence. It does NOT imply support to any political group. It does NOT imply, represent nor support any ideology with an intent on harming anyone. Freedom means freedom from persecution based on any human trait or belief such as, non exhaustively, race, gender, religion, sexual orientation or nationality. The Radio Prepper channel is a technology and science channel with a focus on preparedness and use of radio technology for disaster relief and small group communications in times of need. It is apolitical and open to anyone sharing the same interests. .
Subscribe to my alternate platforms:
ugetube.com/@RadioPrepper
odysee.com/@RadioPrepper:1 oops, wrong address! Correct one below:
odysee.com/@RadioPrepper:d
Now you can buy me a coffee :-) www.buymeacoffee.com/gilg .
Send Bitcoins to: bc1qc5jq4dxt7359sh80lkv9v8rlsgnh322hmn6xyc Send Ethereum : 0xe7cC2e415E0D2d1De91604B2b693f124dfBCf9B8
Send Litecoin : LYwDy55mZSeb1Czx6JUiTS5YkqjfmWKK5H

Наука

Опубликовано:

28 июн 2024

Ссылка:

Скачать:

Готовим ссылку...

Добавить в:

Мой плейлист

Посмотреть позже

Комментарии : 167

@oobihdahboobeeboppah 4 года назад

I must say Gil, for us QRP mountain top and park activators, you are the wind beneath our wings. Your video posts inspire and encourage us to try new things and to warm up the ether!

@RadioPrepper 4 года назад

Thank you! Glad to be of some inspiration :-)

@OH8STN 4 года назад

This was a magnificent video Gil, thank you for sharing 👍

@richardwhitcroftkc3rrw63 2 года назад

Gil.... your videos are always entertaining and educational.

@ratfunkblue 3 года назад

I have really enjoyed your videos. I am a newly minted ham. Got my general two weeks ago. I am now building the the earchi endfed for HF thanks to your videos. You are definitely my RU-vid Elmer! Cheers! ~ KI5JZV

@RadioPrepper 3 года назад

Glad to help!

@richardcooper38 4 года назад

Gil, First off I'd like to thank you for all your efforts in publishing these videos. They have provide a huge amount of instruction for me. I think I've bounced around almost every antenna type for my situation. My wife and I live in our 38' diesel motorcoach. There's limited space for antennas. I will be mounting a screwdriver antenna that I've had been dragging around for years but I've always have had reservations about it's performance. I've read and have listened to almost everything about these EFHW antenna systems over the last couple of weeks. I've been trying to figure out how to utilize a half wave length piece of wire and what I could do. One of the comments from another channel, he had mentioned that he put one of these antennas in his attic running all over the place and still achieved great performance. With this in mind I'm going to try to run the antenna wire from front to back several times and see how this will work. At this point I've got fairly good confidence that it'll perform well for my situation. Have you strung up anything similar with limited space in your trials of ham radio? Looks like most of your CW'ing is out in the beautiful open country. I look forward to your upcoming videos about these antennas. I need to get this put up on the roof of the coach and give it a try so I can get more sleep. Lol Steve Ellington put up a fantastic video of his studies on this antenna system. Well worth the time to watch. 73's Gil and thanks again!

@RadioPrepper 4 года назад

Not sure, that is a unique problem.. On a sailboat you have a mast.. You don't... The question is, do you want to operate while driving? Assuming that isn't the goal, honestly, a HWEF on a fishing pole type mast will serve you best, vertical or inverted V. I don't think it will work folded back and forth, but sometimes weird things happen in radio...

@richardcooper38 4 года назад

@@RadioPrepper Gil, Being able to operate while driving isn't going to happen. Maybe on VHF. I'll have to give it a try and see. If nothing else I'll be able to throw it into a tree when trees are handy. I wouldn't mind if this floated and had a mast. Lol. If I was a able we'd be sailing the high seas years ago. I'll let you know how it works out.

@riaanmaree1132 4 года назад

It's been more than 24hrs and we're all anxiously awaiting the test video! ;-)

@RadioPrepper 4 года назад

It's coming!

@alexandretsilefski2308 4 года назад

Hello Gil. I enjoy your videos. The transformer you discribed for the CB band is working really well, I had contacts with Perpignan and London from the village I live, not too far from Strasbourg. Many thanks! Have a nice week-end!

@RadioPrepper 4 года назад

Excellent!

@survivalcomms 4 года назад

Cool beans ! The step drills (unibit) work great for plastic housings . When I have used a ground reference with an end fed it's really cool to see just how differently the antenna acts over varying soil conductivity. I have had good results with a counterpoise and a random length wire but the RX noise was greater. Thanks for sharing !

@RadioPrepper 4 года назад

Interesting thanks!

@chipandrews2892 4 года назад

Another awesome video Gil...thanks for sharing. I must say that I really enjoy your project/build videos! You explain what you are doing so very well and seeing you do it really puts the cherry on top. Thanks again! Cheers! De KL7CA

@RadioPrepper 4 года назад

Thanks Chip!

@BarefootBeekeeper 2 года назад

A stepped bit makes a better job of holes in plastic boxes than a twist bit, and can be used by hand, without a drill.

@TheDgdimick 4 года назад

Gin, you SO need that 3d Printer. You're the one that recommended the Ender 3 to me, and I've been happy with it for 8 months.

@RadioPrepper 4 года назад

And I still need to buy it! Darn, you beat me to it!

@TheDgdimick 4 года назад

@@RadioPrepper I've bought 2 so far, and normally they are running pretty much all the time, except this week, I'm studying for my Extra Test on Saturday.

@ianboard3555 3 года назад

Completely agree. I bought one a couple of months ago and have been super happy with it. I like the fact that you can start with the basic model and upgrade it easily (better controllers, extruders, etc...).

@robthomas8680 2 года назад

great article - got the parts - building one now - thanks!

@Adam-qd8jh Год назад

I decided to make this design and it worked really well for the cw range on the 40 meter band. Using 29 feet of speaker wire and a 32 foot counter poise. Though I haven’t heard any voice, my water fall on my SDR was packed with cw. I live in between two hills at the bottom and get really bad propagation. But This was my first antenna project after 2 years of messing around with the balun that came with the nooelec SDR. I think I just need to get my antenna higher or lengthen it as I only put it up about 15-20 feet. But I’m excited because I’ve never seen so many signals before. And also I tried using it at night so maybe this is why I haven’t heard any voice on the band. But I can tell this Antenna will pair perfectly with my QRP cw pixie. Thank you!

@RadioPrepper Год назад

Make sure you check the SWR if you transmit with it. You probably will need a tuner..

@georgealbertacanadaeh1038 2 года назад

Thank you, Excellent! I always wanted to see how this was actually done! I have seen and read articles but actually seeing makes it all come together. Thanks again, George Alberta Canada Eh

@RadioPrepper 2 года назад

Glad it was helpful!

@g4okt 4 года назад

'I just can't help myself...." Yes, I know that feeling! Nice vid, looking forward to the testing. I like to use type 61 ferrite for 10 and 6m. 73, Keith

@RadioPrepper 4 года назад

61 would be the right choice for those bands yes. Maybe 52 for 10m...

@DrenImeraj 4 года назад

You should consider getting a step drill bit. They are extremely effective for opening holes in plastic boxes. Thanks for another great video!

@RadioPrepper 4 года назад

I have one, but I need a smaller one!

@jimthvac100 4 года назад

Great Video Gil, I look forward to your comparison of these two 9:1 UNUN's using your new Minion. Lol of course we will enjoy the video regardless what radio you decide to test them with :)

@RadioPrepper 4 года назад

The second video will be out in a day or two!

@davidsradioroom9678 4 года назад

I want to build an unum. Looks like fun and you get something useful from it.

@RadioPrepper 4 года назад

Yep, wait for the second video to choose your toroid! Coming up in a couple days...

@user-mt2qn4yp8w 4 года назад

Man that sucks when the box broke. Keeping fingers crossed that it works. Great video. Take care. , KG7LOI Clark. 73's

@milfamily193 4 года назад

you're awesome! I watch your videos a lot. I actually ordered 3 of the 140-43's last week. They arrived in pieces! The seller didn't package them well at all. But, he loss. Ordered 3 more form a different seller. We will see. Hope it all worked out. 73s from KC2JDR

@RadioPrepper 4 года назад

Better use them for a 49:1 transformer..

@raulponce6276 4 года назад

Nice! I really hope it works! I also bought one and it arrived for me these days. It is a very low permeability (ur = 10) powdered iron specified as low losses in "all frequencies" (??). I have been researching, and it really makes sense that it is a core with lower losses at high frequencies, since the material allows less effect of magnetic hysteresis and circulation of Foucalt currents. The phenomenon is obseveed in induction furnaces, where the core must necessarily produce heat. conversely, especially in QRP, any loss value becomes significant. than, this core would be better. In my case, I will have to wait a little longer to test because I live in an apartment on downtown. I wait for your opinion in another video too! haha

@RadioPrepper 4 года назад

Wait for the second video in a day or two...

@n8nkqrp595 4 года назад

It's all about Al value and thus the minimum usable frequency of the unit. And to a secondary matter- self-resonances of the UNUN with no load connected. T106-2 has an Al value of only 135, severely limiting it's low band use, as you mention. For what it's worth, the Al value of the FT140-43 is 885, 4 times that of the iron core, giving you 16x the inductance per turn. Much to consider. 73

@RadioPrepper 4 года назад

Great info thanks!

@chrisb3989 Год назад

Very neat build well done……..

@ae1tpa92gwtom2 4 года назад

Gil, ur great, n everyone , im sure everyone likes the look on yr face, when u cant help yrself, u give all of us education, courage to do it, n ways to enjoy the hobby,.. good on ya,.. 73 my friend

@RadioPrepper 4 года назад

Thank you! Always nice to hear :-)

@jamdiversified9698 2 года назад

Quick tip, If you want to get hot glue off of something, spray it with isopropanol (IPA) and it will come right off clean.... From smooth surfaces at least.

@markg6jvy135 4 года назад

“Toroids, washers wingnuts and 22awg wire, everything to make a man happy” 😂classic line Gil 😂👏 I find a cone step drill sometimes prevents that snagging of fluted drill bits when going into thin material.? Great video as always 👍

@RadioPrepper 4 года назад

Worst thing is, I have one!

@hobbyrob313 4 года назад

YES yes yes this is not strange what happens here! drilling holes in this way requires for it! but don't say that these boxes are junk, that's not fair! ( And +1 for Denis Dimick!!! ) Greetings from NL Rob

@ssubaihi 4 года назад

I am HZ1-si (Suhail) from Saudi Arabia First, thank you so much for this Great channel .. I heard that some (Core materials) have some advantages over others, Particularly in (Receiving mode) which let your antenna has less noise.. Perhaps That's is why some of the End-Fed producers marketing some of End-Fed antenna as a ((SWL End-Fed antenna only) with limited TX Power capability .. Hopefully you shed some light on such (the important secret) .. I say this because I made myself End-Fed Half-Wave antenna, it is very good antenna, I have no big problem in (Transmit Mode) as I can compensate for Far Away DX station with a little push of TX Power ... However, I am still struggle in Receiving Mode especially with some weak DX signals .. Besides, I don't have much (Horizontal space) for the "Wonderful Beverage Antenna" .. By the way ... Generally Speaking ... which is better in (Receiving Mode) .. (9:1 Un-Un*) or (49: 1 EFHW**) ? considering Both Antenna have the same Length @ same Band .. *considering a proper Ground or Counterpoise applied.. **Considering a proper Line isolation applied.. Please Help ..

@RadioPrepper 4 года назад

That is a very good point. I did not test noise levels... The second video will be out soon.

@HKey_Root 2 года назад

'Don't make one yet as I don't know if it works'. Brilliant. Love it.

@RadioPrepper 2 года назад

Turns out, it doesn't!

@HKey_Root 2 года назад

@@RadioPrepper 😂

@scottcarter9975 4 года назад

Another good video Gil. Thanks. Question: I have a spare FT-82-43. Do you think it would work for a 9:1 for portable up to 10 watts? Thanks, Scott kw4jm

@RadioPrepper 4 года назад

I will be able to tell you in a few days... Wait a bit... I would make a 64:1 transformer...

@johnk8091 4 года назад

Great instructions to build the 9:1 "OON OON". I still far prefer the 49:1 and EFHW. Looking forward to your testing video to see how the two compare

@RadioPrepper 4 года назад

Me too..

@mabo4848 4 года назад

TNX !

@toddmathews7828 2 года назад

I've found that using a forstner bit works really well for drilling through those cheap plastic boxes. Sadly, it took me more than one box to discover this.

@andreVE4BK 2 года назад

I use a stepping bit… slowly. Never had a breakage

@WillemvanderHouven 4 года назад

Nice video Gil, but could you explain te windings again with a total wind of the emailed copper wires i count 8 turns ? at 5:30

@RadioPrepper 4 года назад

Count the turns on the inside of the toroid... Every time the wire goes through the code is one turn.

@tanglewoood 2 года назад

Builders might like using a step drill with 1/32" steps. They are available from a number of sources including Amazon.

@rickmckee6698 2 года назад

Just use a step drill !

@RadioPrepper 2 года назад

Yes, I have one..

@luismirandakunert3475 4 года назад

Nice, congrats DO you know where can I get(buy) a set of this toroids to make inductance as my pleasure? Thank you

@RadioPrepper 4 года назад

I get them all on Ebay..

@mikes6844 4 года назад

Try putting a clamp both sides of the box before you drill the hole as it should stop it from splitting on the basis you are not using too much downward pressure. Or use a vice. Another very useful vid, I can't keep up with you! Just finished building a 49:1 balun. Will be testing some EFHW wires with it over the weekend. We are still in lock down and will be for a while longer, BYOTA (Back Yards On The Air) for me. Conditions quite good for a little QRP. Take care... 73 de M0AZE

@RadioPrepper 4 года назад

I should have done that!

@napomania Год назад

good job . next time try to use a conic drill hole 🙂

@midwestavaitionmx5503 4 года назад

I’m brand new to hf, love the information in all of these videos. Also most interested in portable setups. Couple of questions, Do BNC and so239s serve the same purpose? Where do you get your materials for your projects? Thanks 73deW0DJW

@RadioPrepper 4 года назад

Hi, Ebay.. BNCs are just smaller and easier to use; same purpose.

@riccardomilan Год назад

Thanks so much Gil! is it mandatory to remove the insulation before join and weld the wires correct? I'm doing a similar UN:UN with 16:1 9:1 and 4:1

@RadioPrepper Год назад

Hi, oh yes.

@gordselectronicshobby3853 4 года назад

Step drills would b better to use as well as a reamer for fine cuts.

@andreVE4BK 2 года назад

Gil… if you identify your wires individually (you’ll need 2 markers) before you start winding, you will save time and effort at the end. 73 Andre/M0RAV

@jamescoffey5225 4 года назад

I have always found that when drilling into plastic (boxes) I use a smaller drill bit or a few smaller drill bits and then start drilling, gradually increasing the diameter of the hole until I get to the size of drill bit I need for the BNC or whatever attachment I am using. Could you have made better use of a metal box for the UNUN if you could procure one for a reasonable cost? I have never tried using a metal box for a balun or an unun. AE5ZX

@jamescoffey5225 4 года назад

Of course I am usually too lazy and end up just drilling a hole of the appropriate size in the plastic box, and then just hope for the best. 😊

@Steve-GM0HUU 4 года назад

For plastic, I drill a small hole then use a reamer to enlarge to exactly the right diameter. This way you can make holes of any size (3mm to 13mm) with just one 3mm drill bit and a reamer.

@19134ANDY 3 года назад

Nice video, do you have one on how to make a 6:1 unun

@RadioPrepper 3 года назад

I have one on the 9:1.

@radioastronomy2001 4 года назад

Like always very interesting video. Thank you! You can test it by loading it with a 470Ohm (ideally 450Ohm) resistor and running antenna analyzer. It should show around 1:1 SWR across all bands. I used a yellow core (+-4cm in diameter) from an old PC power supply. It does work well from 80m to 10m. The materials seems to be "#6".

@RadioPrepper 4 года назад

Not the 9:1. The 9:1 needs to be tested with a resistor in the 400-600 Ohms range. A 49:1 or 64:1 however is tested with a 2500 to 4700 Ohm resistor. See: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-0zF7bDoqkG4.html

@radioastronomy2001 4 года назад

@@RadioPrepper Normally you can not buy 450Ohm resistor but 470Ohm seems to be close enough where 400-600Ohms seem to be too far. I agree for 49:1 transformer you would need something like 2450Ohm but again you can not buy one exactly like it. Most likely you would have to combine 2.2kOhm with something else (330Ohm) or use 2.7kOhm. So I still think 470 Ohm is a good approximation when testing 9:1 unun. 470 Ohms / 9 = 52.2 Ohms. Where 400/9=44.4 (my "." is yours ",")

@ricktafied Год назад

@@radioastronomy2001 Use a pot and set it to 2450 ohms?

@radioastronomy2001 Год назад

@@ricktafied Good idea. Thanks.

@joecraft4409 2 года назад

Hey Gil, today I heard that it is not recommended that one use a RED toroid to make unun. I have to go back and read the article for understanding.

@RadioPrepper 2 года назад

Well, it's not recommended but it works better so...

@captainmarvel6031 4 года назад

Thanks for the video! One question, do you know what guage wire to use for it to handle 100 watts, or would I need a different toroid also?

@RadioPrepper 4 года назад

It should take 100W, 1mm wire.

@barrykery1175 2 года назад

@@RadioPrepper The wire can easily handle 100 plus watts. The heating of the core is the limiting factor. Depending on what UnUn or balun you make, I've already run 1500 watts using an FT 140-43. Yet a 64 to 1 UnUn for a HWEF won't handle more than 50 watts without getting hot. Barry, KU3X

@RadioPrepper 2 года назад

And risking permanent damage...

@MrLittlmike22 4 года назад

great video as always - it woudl be greta to move up to 1:49 too!

@RadioPrepper 4 года назад

I definitely do prefer 49:1 with a half-wave wire..

@flipster7285 2 года назад

I love watching your videos. I am learning quite a lot and I am now starting to build a few things to play around with. I do have a few questions though, maybe you could help me get some clarity. 1) what would the max power be that I can put through this FT140 9:1 unun? If I want to go up to a max of 500w, would I be better off with a FT240-43 or perhaps 2 stacked FT240's? Unfortunately toroid cores useful for RF are not easily available in South Africa and they are fairly expensive when we do get them so I do not want to buy loads of cores that will not get used. 2) when it comes to winding...... Adam (K6ARK) built a small 9:1 on an Ft50-61 but he does not use 3 seperate wires, he winds that with a single continuous wire. (I built that qrp antenna and it works really well). Would that same technique work for bigger unun's or would it be better to use the seperate wires and solder them together after winding? Looking forward to more quality lessons from Master Gil!

@RadioPrepper 2 года назад

All right: 1. You don't build a 9:1 UNUN, which is for random wires with a 43 material core. Those are for 49:1 or 64:1 and half-wave wires. Watch the following video:

@RadioPrepper 2 года назад

ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-0zF7bDoqkG4.html

@RadioPrepper 2 года назад

If you want to build a 49:1 or 64:1 for a half-wave wire, you will need to stack three FT-240-43 cores. I do not recommend using a 9:1 with a random wire for high power.

@RadioPrepper 2 года назад

2. Yes, but need to test... 3. 500W is useless. Anything above 30W is a waste of electricity and not needed a vast majority of the time. Invest in antenna building materials and knowledge instead of an amp.

@robthomas8680 2 года назад

um - step drills - $12 on Amazon or your locate hardware - don't leave home without 'em! :)

@AndrewBryantPianoTuner Год назад

When you twisted the 2 wires together did you remove the insulation ?

@daveduffy2292 3 года назад

In some vlogs I noticed that they use insulated wire. Does it make a difference

@RadioPrepper 3 года назад

Not with material 43. Note that enameled wire like I use is insulated.

@AndrewBryantPianoTuner Год назад

When you twisted the 2 wires together did you remove the insulation or do you leave it in place ?

@RadioPrepper Год назад

I left it.

@StephenFarthing 4 года назад

You will find it easier, and safer, if you use a step drill bit rather than the ones you have. I've probably a spare one if you want it.

@RadioPrepper 4 года назад

Worst thing is... I have one! Thanks though :-)

@carlossilva.k2wc.542 Месяц назад

First, thank you much for sharing your videos with all us, I have a quick question, How much power can this core hold in digital modes (FT8)? Is 30 or 40 watts okay?, Thank you in Advance,73 de K2WC

@RadioPrepper Месяц назад

Hi, 30 should be OK, though with FT8 5W is enough. BTW 43 material isn't good for a 9:1. Check my other videos. Use a #2 red core.

@carlossilva.k2wc.542 Месяц назад

@@RadioPrepper Thank you for your prompt answer, your are talking about the T200-2 toroid?

@RadioPrepper Месяц назад

Yes, or T130-2. I don't remember which one I used, it's in a video..

@calvinlong1265 Год назад

Do you know if you can safely use an unun on a dipole?

@RadioPrepper Год назад

You would not use an UNUN on a dipole, as it makes no sense to do so..

@Pauldeva 4 года назад

What are dimension of the box pls, '73 de YO2MMJ

@RadioPrepper 4 года назад

50x80x26mm.

@tackanderson4270 2 года назад

How can you use a multi-meter to test "short" when all your wires are touching and already shorted"? Unless the "lacquer" wire coating is enough to separate them and keep them from shorting out?

@RadioPrepper 2 года назад

The enamel does insulate the wires but the circuit itself is such that everything is a DC short, so a multimeter is useless. It is however not a short for AC at the intended frequencies.

@tackanderson4270 2 года назад

@@RadioPrepper Assuming those frequencies are isolated (in bandwidth). I'm assuming this is what you meant as "intended frequencies". However, once ground is introduced to A/C, a short results, even an isolated ground (not sure of a radiated or ground plane). So this means under operation, those wire must be isolated? Testing however, must be done with an O scope. I do think you said that the multi M would be useless, so point understood.

@RadioPrepper 2 года назад

Actually I should have said "the turns are insulated," it really is only one wire... See my construction videos...

@tackanderson4270 2 года назад

@@RadioPrepper Sounds great....

@thierryruiz9205 4 года назад

Bonjour Gil, très bonne vidéo sur la fabrication de transformateur, aurais tu la possibilité de joindre les liens pour l'achat des toroïdes, merci d'avance, 73 F1RJC

@RadioPrepper 4 года назад

Sur Ebay, fais une recherche, il y en a plein...

@thierryruiz9205 4 года назад

Bonjour Gil, je viens de le faire, j'ai trouvé mon bonheur, merci Thierry

@technicmasters7936 2 года назад

Does this work with FT14-43 toroid or would i need to have a different number of turns? And if so, how many?

@RadioPrepper 2 года назад

No, a 9:1 does not work well with an FT-140-43. Use a T130-6.

@technicmasters7936 2 года назад

@@RadioPrepper Probably just a typo, i meant FT14-43, i think i have a T130-6, ill give it a try, thanks

@RadioPrepper 2 года назад

I never heard of an FT14-43... See the EARCHI (Hawai Radio Club) pdf file on the matter...

@technicmasters7936 2 года назад

@@RadioPrepper oh, sorry FT114-43

@technicmasters7936 2 года назад

@@RadioPrepper Would FT114-43 work?

@laurentboussuge7368 4 года назад

Bonjour merci pour vos vidéos pouvez-vous la faire en français ?

@RadioPrepper 4 года назад

La seconde sera aussi en Français!

@laurentboussuge7368 4 года назад

@@RadioPrepper merci

@svtelos4726 3 года назад

Its possible to punch holes in thin plastic, with an ordinary hand hole punch. A single, not the triple for notebooks. Or, for thicker plastic, a leather hole punch. much cleaner and less scarier than watching Gil and a drill press.... :) !!

@RadioPrepper 3 года назад

Not that kind of plastic but those work very well on Altoid cans!

@svtelos4726 3 года назад

@@RadioPrepper Then, we should put a nice small drill press vice on your Amazon Wish List for Xmas! Thanks for your videos. I just got my General License and am looking forward to hearing you on the radio. Alas, Im in San Diego. Your vids are both entertaining and very instructive. Thanks. :)

@RadioPrepper 3 года назад

Thanks! I have one but it's up North at my parent's...

@HKey_Root 2 года назад

Actually could someone explain why this isn't a balun? Still learning.

@RadioPrepper 2 года назад

BALUN is balanced-to-unbalanced. UNUN is unbalanced to unbalanced. Example: An end-fed wire is unbalanced, coax is unbalanced, so you use an UNUN. A dipole is balanced, coax is unbalanced, so you use a BALUN.

@HKey_Root 2 года назад

@@RadioPrepper Of course it is. My bad. So twin flex from say a homemade Magloop would need a balun? 9:1?

@RadioPrepper 2 года назад

What is twin flex? Are you sure you mean a magnetic loop, not a regular loop? Mag loops don't need impedance matching other than the big capacitor in the loop...

@HKey_Root 2 года назад

@@RadioPrepper We're now talking at cross purposes. Thanks for your input.

@oobihdahboobeeboppah 4 года назад

The Fairite type 43 is not the best material for the lower bands on HF. If you look up the specs at Palomar Engineers you will see that type 43 is better from 20m up possibly as high as 6 m. Type 31 is a better material covering 160 meters to 6 meters. Type 41 will work but not as well.

@RadioPrepper 4 года назад

In theory yes, but in practice, everything I have ever found that works points to 43, 52 and 61 for 80 to 6m, with 31 used for chokes. Maybe the choke vs transformer is the difference...

@oobihdahboobeeboppah 4 года назад

In recent months, I built 9:1 ununs using both. Afterwards, I used a 50Ω dummy load at the output of the unun, and my analyzer at the input. What I found was that in both units, the response curves almost paralleled the Fairite specs exactly. I've used both for QRP, and both work, though the 31 works better: Louder signals on receive and better signal reports on transmit. I'll have more time to test with the warmer weather. Ahhhh, the fun of Amateur Radio!

@Steve-GM0HUU 4 года назад

@@oobihdahboobeeboppah just wondered please - on which bands did you find the 31 was better?

@mortimersnerd801 2 года назад

@@RadioPrepper Your correct Gil...and Palomar sell 31 material specifically for common current and noise chokes... other than 160 and maybe 80, meters... 31 material is not recommended for the high bands.. took in their seminar at the Yuma hamfest. in how they explained this.

@rickmckee6698 2 года назад

An FT140-61 core works much better 10 thru 80 meters.

@expert244 4 года назад

Now I want to make an UNUN.......

@RadioPrepper 4 года назад

Make a 49:1 transformer rather..

@jamesgeorge1709 Год назад

Get yourself some step bits you'll never go back to metal boring bits.

@Ryo_Saeba 4 года назад

Bonjour, je vous ai entendu au col de coursegoule alors que vous étiez au col de vence. Vous avez donné l'adresse de votre chaine, je me suis donc permis de vous écrire pour vous dire le bien que je pense de votre chaine et que la liaison avec un petit talkie était sans fioriture

@RadioPrepper 4 года назад

Super merci! Je suis de temps en temps à l'écoute sur le relais du Mont Agel et Vial..

@warplanner8852 Год назад

Gil, French don't say "merde" anymore? 😅 For the bigger holes, use the a reamer, Gil. A little more work bit minimizes the chance of shattering. 72/73 de William, k6whp dit dit

@corbeijersbergen9999 4 года назад

Gil, don't blame the cheap plastic box, blame the wrong type of drill..

@RadioPrepper 4 года назад

Or myself.. ;-)

@M0RMY 4 года назад

Gil Brilliant as usual. I really enjoyed this. I have emailed you a message about a project you may be interested in conjunction with Callum DX Commander. Tom M0RMY

@RadioPrepper 4 года назад

I'll check that address thanks!

@Subgunman Месяц назад

Old joke about thread lockers, "Cross threading works better than locktite". NOT! I found that buying and using the longer and narrower step bits will not destroy plastic cases, the fatter and shorter step bits will cause cracking of cases, steps too large.

@kennethschultz6465 4 года назад

Hot glue ain't water tight .. you truly want ppl to fail

@RadioPrepper 4 года назад

It doesn't need to be watertight. This is for temporary portable operations. Even for a permanent installation, these boxes should be vented to avoid condensation.

@kennethschultz6465 4 года назад

So you are a Fan !! Well I'LL never be !! I tryed 5 difrent designs Not one of Them worked in any satisfictory way !! It's a crappy antenna !! In any way.. waste of time

@RadioPrepper 4 года назад

Fan of hal-wave end-fed antennas, not random-wire antennas with a 9:1 UNUN... What kind did you try and how?

@warplanner8852 3 года назад

Gil, I am told that you can TWIST the wires with no adverse effect. I am going to build a one and I will report back. de k6whp