This EFHW will DOMINATE the End Fed Antenna Market!

K6ARK took tiny and made it big, but still portable!
I was honored to receive a sample of a concept Adam is working on. In the future, I will be providing a build video for both this and the 20w EFHW kit from K6ARK.
This kit was easy to build and uses the same concepts as his other EFHW kits available at Amazon.com - amzn.to/39NmUbS (All links provided through Amazon.com are affiliate links)
For this build, I used a T140-43 torroid: amzn.to/3OmcQFF (7.99) or www.jpmsupply.... (2.69 plus shipping) or
JPM on ebay - www.ebay.com/i... (2.89 plus 4.70 shipping)
and a 3KV 100PF SMD capacitor or a regular 1KV-3KV capacitor will work if you do not want to fuss with SMD - .
Cool Banana Plugs shown in the video - amzn.to/3OqXznm
The antenna wire used was BNTECH GO 26AWG . I used around 65 feet for my EFHW.- amzn.to/3QHrYzb
Finally, the magnet wire I used was BNTECH GO 20AWG - amzn.to/3xLIxkY
Testing this on SSB, I did not have any issues operating at 100W . The type of contacts I was making were quick POTA style contacts.
What do you think of this potential product by K6ARK?
NOTES:
I spoke with Adam after testing: he mentioned the possibility of adding a compensation coil:
""Get it resonant on 40m with extra wire folded back on itself, then check 20, 15, 10. If 20, 15 and 10 are above the bands, a coil at about 6ft from the feed point will help. 10-12 turns on a 3/4 inch form (I use black plastic drip tubing in my kits). You'll have to lengthen the wire slightly to get it back into resonance on 40m, but then 20, 15, and 10 should have the dip right in the bands"
This was a fun kit to build and I will be excited to see where K6ARK takes this.
#hamradio #efhw #antenna

[@jeremytanzer279]

Even if Adam just produced the board and gave a bill of materials/instructions... Yeah. I'm in line.

[@laszlokovacs8827]

This right here. I have plenty of toroids, magnet wire, heat shrink and 239's. That would take some of the pressure off of Adam assembling the whole kit.

[@NimblyJimbly]

Agreed. I would buy it in either a kit form, fully assembled, or just a board with a BOM. 🤘🏼

[@coltendoc]

Id buy it.

[@scottgarvy]

Me too. Even just the board for SO-239.

[@sandhill9313]

Having to mail out just the PCB's might make the whole process so much easier on him that it would be doable. Please 😀

[@Cardassiaprime]

Loved Adam’s original design But I’m up for just the PCB being available, for the compactability ( I’m being told that’s not a word) it is now. Cheers guys You both have great channels.

[@K5azz]

Great Video, I'm glad Adam mentioned the Compensation coil. Lots of great info about this from Steve Ellington's video's on the EFHW. I would definitely buy a kit from Adam if he made it available. His PCB is a great innovation.

[@FITFO]

This would be a go to, if i would come to market. Something that still fits in the pocket and can be used for QRP but also if i want to bring the ft 891 along

[@scottb7007]

Just want to say… Your videos and content are a joy to watch. Keep them coming

[@HAMRADIODUDE]

Thank you very much!

[@HOAHamRadio]

Thanks for sharing this. All I have to say is "take my money!" I'd buy multiples of this if it comes to market.

[@radiotests]

Sure like to șee do a build on the for 3 and 10 😁

[@d3w4yn3]

Your call reminds me of an old war movie every time I hear it, and I don't know why! Tora! Tora! Tora! Also, great video, I'm doing a lot of EFHW antenna exploration and am really interested in the K6ARK, and if he releases this version, I WILL BUY IT!!!

[@HAMRADIODUDE]

Awesome to hear you're interested in building antennas / efhws. The kit has come for sale a few times now and sells out fairly quick. Next time I see it, I'll make a community post. Thanks and good luck!

[@eldavis1332]

Yes I would buy kit, or any iteration of a kit, even if it was just the PCB board and a list of other materials to buy. I've already bought six of Adams 5 Watt and 20 watt kids and have built both nfed halfway and in-fed random wire. They've all worked beautifully!

[@HAMRADIODUDE]

They do great. Adam made some changes which i just tested. The changes show he puts a lot of thought into the designs. Check back next week for part two! I think Adam will discuss it being a kit or parts list... Thanks!

[@johnwilson9303]

Would love to see you deployment of the antenna for portable operation and tweaking the length and utilization of the banana plugs. Great video, thank you!

[@Rolfunther]

I need another EFHW like I need another hole in my head....but I'd buy/build one of these in a heartbeat for the form factor alone. I've built Adam's 20W version and it's value for me is in its intelligent design. Great video on your part, by the way.

[@HAMRADIODUDE]

Thanks! I enjoyed it. I have a part two coming out next week. A few modifications/upgrades, a conversation with Adam, etc. I appreciate it!

[@OVCArchion]

I would absolutely jump on this, even just the PCB and a BOM. It's perfect for my needs.

[@HAMRADIODUDE]

Awesome. Adam was telling me he's thinking he'll release both kits and just the board with a BOM.

[@HisWayHomestead]

Make sure Adam knows that I would love to have this antenna kit!!!

[@POTA-QRP]

I would love to have this antenna in my kit!! I could use it on a fly in Canadian fishing and POTA trip this summer!!!

[@jmount1200]

Adam's EFRW and 3 element yagi have helped me with plenty of contacts. For some reason I have trouble tuning the EFHW but I will buy all the parts in anticipation of a 100W EFHW.

[@thormusique]

OMG, this is awesome! And thanks for sharing. I would definitely buy the 100W version; I do hope Adam decides to offer it. Cheers!

[@HAMRADIODUDE]

He's going to! I have the latest version which I need to assemble this week. Keep an eye out

[@thormusique]

@@HAMRADIODUDE Excellent! Thanks so much for the heads up!

[@Dusty_Ham]

This looks amazing! Great design by Adam, and great build by you Sean.

[@K3JRZOnTheAir]

I’ll be keeping my eye out for this. Thanks for sharing! 73!

[@barrykery1175]

Nice antenna. Nice video. Since the center pin of the SO 239 comes apart with heat, before soldering, attach a PL 259 to it for a heat sink. Barry, KU3X

[@HAMRADIODUDE]

Whoa! You just gave me some great knowledge. I'll pass that on! Thank you so much!

[@carolannefisher1516]

I built Adam’s 20/30/40 meter ultralight before he released his kit. Love it! Now for a 100W version! I’d much rather build it from a kit from Adam! I already bought two of the QRP kits….

[@GeorgeAdams]

I was just building out an HF go kit and thought about picking up his 20W kit. This bigger version would fit perfectly in a little pocket I have earmarked for the antenna.

[@froto1369]

Love the Tom Hanks reference. LOL Haven't seen that movie since I was a kid.

[@HAMRADIODUDE]

Thanks LOL. I take some enjoyment in making these videos with a little bit of a twist. There is an actual zoltar machine near my house, but I didn't have time unfortunately. I'm glad somebody got the reference! 😎

[@froto1369]

@@HAMRADIODUDE is the zoltar at the volo auto museum?

[@HAMRADIODUDE]

It is!

[@froto1369]

Now I have to go. LOL and I can activate the bog at the same time.

[@HAMRADIODUDE]

@@froto1369 yeah totally! It's like 4 minutes away. Let me know if/ when you go and I'll meet you at the bog

[@guykovacs9334]

Would love to see this on amazon as a kit to shoot down all the expensive antennas, I don't need nothing more than 100 watts even for my base station at home, Thanks video dude, great design Adam

[@HAMRADIODUDE]

I agree. Adam does amazing work. Thanks!

[@SteveH-TN]

Indeed a great way to wind EFHW. Despite being from Chicago I always preferred ketchup on my Vienna Hot Dogs when at Wrigley Field & in lunch room at Lane Tech especially during Taft - Lane Football game at Lane Stadium too 🤪😎

[@CommanderBacon64]

I just bought the kit and need to get off the couch and build it!!!

[@haroldskinner1783]

absolutely would buy one if it were to come available. Great video - thanks for sharing

[@HAMRADIODUDE]

Thanks for watching! I'll have a new video on this antenna and some updates, next week.

[@marktorigian5647]

I would buy right now . Good work Adam

[@swenner64]

I love his Qrp antenna, I would buy the 100w for sure!!!

[@HAMRADIODUDE]

Check back next week for part two! I think Adam will discuss it being a kit or parts list... Thanks!

[@JhKnife-OZ4HJ-Jimmi]

Cool, I got the same idea. I have just build a 9:1 just like it for a random wire antenna…👍🏼 It’s nice when the unun/transformer fits in your hand…😄

[@johnemmons9087]

How about winding the aerial in a chalk line case? I think it’s a very viable, compact, and very protective way to keep the aerial in good shape. Thanx for the vid!

[@HAMRADIODUDE]

Working on a chalk line antenna like the one I recently reviewed. .. It never occurred to me to use Adams board, I'll see what I can do

[@dwaynehoffmann8538]

I'll take one! I would love to buy it as a kit, and build it myself. Ty

[@donaldsmith3048]

That may be good. I just got the EFHW kit from ARRL. It much larger and heavier. But I don't do SOTA, so it doesn't matter that much to me. At 75 I don't think I will start SOTA. But I will send this video to some younger friends that this should be something that they may like. That would be good for POTA and ARES.

[@DonzLockz]

Great little kit, I'm sure it would be very popular if it was released.🍻🤓

[@KC9RXP]

Love the Big reference. Lol

[@RMJ01]

Yes bring it to market

[@cschmittie3284]

Yup! I would buy one! Keep us posted! W0AP

[@tglenn3121]

Yeah, for sure I'd buy one of these for 100 watt use.

[@9999plato]

I'm buying 2. I might try multiple different windings.

[@PortableRadio]

Thanks for the video, dude! If you want to have better efficiency on the lower bands, use 3 instead of 2 primary windings. Owen Duffy has a handy calculator for this and much more. If you're interested in more resonant bands, I wrote a document that shows a solution for a 20m long 7-band EFHW with one switchable coil. Have fun while experimenting, 73 de HB9EAJ, Stephan

[@HAMRADIODUDE]

You're the switch guy! I lost the Article for whatever reason. I wanted to thank you for it.! I'm going to try it and make a video! Than you so much!!

[@m0aze611]

Downloaded the document a few days ago and I have nothing but praise. I've used EFHW for many years both at home and out in the field and there are many variables to making and setting up and I guess you have to decide what's best for your operating. In general I use a 10 meter mast and mount vertically, however some recommend as Stephen does, mounting the UNUN at least ½ meter above ground. I agree, but that makes it a little impractical for my own personal field use for 20 meters and above using single wire resonant lengths. My challenge is to make something practical for 40 and above out in the field. The great thing about our hobby is that every day is a learning day and grateful to hams such as Stephen in producing such a useful article. 73 de M0AZE Mike

[@russellwatkinson]

I’m looking forward to seeing this :-)

[@pauljameson1]

With the price point that he operates at, I’d most likely buy one! It would be nice to stray away from the KM4ACK EFHW size and power limits.

[@HAMRADIODUDE]

Check back next week for part two! I think Adam will discuss it being a kit or parts list... Additionally, I test in depth, this EFHW at 100w on multiple bands for an extended time.

[@aldewitt9]

I would buy it. Absolutely.

[@CPLBSS88]

Uhh hell yes!!! Id buy several...

[@charleshall7378]

Great antenna. I’m sure it will sell like hotcakes. I would buy them. Chuck

[@HAMRADIODUDE]

Awesome. He already sold a few batches. I think he has plans for another batch soon.

[@frankbrown6419]

We need it

[@HAMRADIODUDE]

Check back next week for part two! I think Adam will discuss it being a kit or parts list... Thanks!

[@weasleyoc]

KN6RHV - I would definitely be interested.

[@HisWayHomestead]

A pcb only option would work for me too!!! Please Adam!!!

[@RLKD8DNS]

Hell yes I would buy one.

[@HAMRADIODUDE]

Check back next week for part two! I think Adam will discuss it being a kit or parts list... Thanks!

[@wildlandoutdoors51]

Id buy one for sure if Adam made the kit or even just the board with a parts list.

[@CapeCodCNC]

I would buy one for sure!

[@tomnapier3910]

I'd greatly appreciate it if/when his kit becomes available

[@davidshermanlittle919]

I’ll purchase more than one. AF5U 73 Dave😊

[@DonzLockz]

I will be asleep for the live show. Here is a #1 to enter just in case you do a giveaway!.🤞😜👍#TeamReplay FTW :)

[@Brighamdoc]

It would be a great antenna for my operating - I would buy one but I’m sure I’d be waiting in a long queue

[@Cunneyworth]

I really want this.

[@Jake_WY7JMS]

I’d like to see just the PCB for it, or a place to possibly get the PCB from. I’m all about frugality and his projects appeal to me. I hope that he makes this possible.

[@revbikerbigd8664]

Where can we order just the circuit board from? A link ?

[@garylanders1470]

You list websites for all components except the board, is it available? Thank you kindly

[@raithjames860]

Question is 26 awg wire sufficient for 100watts? Not sure that's why I am asking.

[@HAMRADIODUDE]

I haven't had any issues, more testing will resume shortly, but I believe it's fine for ssb use.

[@jlday70]

Please tell Adam to bring this to market. Love the concept, and would love to have a portable EFHW that can handle 100w+. Dumb question though, where did you get the small gold connectors?

[@HAMRADIODUDE]

amzn.to/3OqXznm

[@jlday70]

Thank you sir.

[@KeepEvery1Guessing]

Certainly if Adam offers it, I would go for it. A board and a BOM would also be interesting. But I would also consider going from scratch if Adam isn't into it. I'm guessing that cooling is better than the plastic box versions most of us already have, but I don't know what the R value of shrink wrap is (I'd probably go with white).

[@HAMRADIODUDE]

Check back next week for part two! I think adam will discuss it being a kit or parts list... Thanks!

[@mikesmithg0rfd356]

thank you

[@Fireguy-]

Adam, make the kit and I'll buy it. I already built the QRP version. :)

[@rogerweiss9573]

I would buy one for my radio go kit.

[@HAMRADIODUDE]

Thanks for watching! I'll have a new video on this antenna and some updates, next week. Information about the kit may be provided.

[@skater4169]

Thanks for the video and I have looked on Amazon but it’s saying that the product is currently unavailable.

[@HAMRADIODUDE]

Yeah unfortunately I don't know which product you're talking about, but also if it's a k6 a r k products, you might want to ask him. This larger kit isn't available yet

[@stevek5smh318]

Would probably purchase the kit if he made it availble. Using the smaller (BNC) one now, works great.

[@radiotests]

hey neighbor! You trying to kill Adam with work? He has a setup for your HT that is amazing!

[@durk182182]

Where did u get those banana plugs? Thanks KO4ACA

[@HAMRADIODUDE]

amzn.to/3OqXznm (affiliate link). I forgot that in the description. Thanks!

[@spencerhochstetler]

Thanks! Can you please post a link to your "high quality" SO239 connector?

[@HAMRADIODUDE]

Maybe. Did I say that my connector was high quality

[@mareksp9tkw908]

I'm concern about 100W on FT140-43 especially with 14:2 turns. I made such transformer and its efficiency was around 70-75% at best. 21:3 turns efficiency is about 85-90%. Have you done some more extensive testing @100W and checked temperature of the core?

[@HAMRADIODUDE]

I have not yet. I'm waiting for some updated boards to arrive and then will test the efficiency and extensively test it. I plan on having longer conversations and running ft8 to get a better idea of the maximum power before reaching saturation. It will probably be about a week or two. During the time, I'm planning on winding two up, one with 3 turns on the primary and one with two, to get a better idea, understanding. I'll definitely keep you posted. Thank you for asking

[@corradoQC]

Packetenna EFHW antennas are rated 100w and the core looks smaller than a 140, I push 45watts on FT8 through 30 feets of RG58 and I don't have any Issues. I'm probably at the limit. It might not be a 43 core on the Packtenna, it might be something more efficient.

[@K6ARK]

Without much testing other than Field Day operating, I would suggest that 100w is fine for lower duty cycle operation (25% or less TX) and 50w should be reasonable for 50% duty cycle modes like FT8. Another option for 100w operation would be to stack a couple of FT140-43 toroids.

[@joeyperez8581]

I'll buy a half dozen of them to give to my friends

[@carlhumphrey4155]

I want one!

[@HAMRADIODUDE]

New episode coming soon.

[@yakovdavidovich7943]

One turn on the primary is nuts, though. That's only 78 ohms of inductive reactance in the winding on 20m, which is way less than the 5x rule of thumb. You should be targeting at least 250 ohms on the lowest band. That's 3T on an FT140-43. You'll suffer worse coupling and reduced efficiency with only 1T. When I made my most recent one, I actually built it on a BN-43-3312 binocular toroid. One turn on that is 312 ohms at 40m -- by using that low primary turn count, I was able to avoid the need for any compensating capacitor due to far lower leakage inductance. I wonder if a BN-43-7051 would have sufficient thermal properties for 100W?

[@HAMRADIODUDE]

I'm sorry, maybe there was confusion.... I used a 2 to 14 turn ratio which reduces to 1:7 ... 7X7 = 49. I'm definitely not using one turn.

[@casevideo9880]

Please do this new kit with a SO-239 kit…

[@rodgermckeon]

I'd buy that!

[@bradenglettkd8zm69]

How is this any better, more durable or more compact than the Spark Plug 64:1 EFHW?

[@HAMRADIODUDE]

Since being a prototype,a larger core was added. I tested it on ft8 for two hours at 85-90w (I believe, I have that information somewhere), and the core wasn't warm. But yes, the original version in this video had a t140-43. Thanks for watching

[@MrLittlmike22]

ghreat video 2 quick questions if I may how long is cabel originally (at your preferencess - when you measurewd with analyzer)? also when the antenna was in a sloper configuration did you run a coax to the transformer? or simply had it at radio (like the smaller version)? great video

[@HAMRADIODUDE]

Both great questions. Just about 65 ft on the antenna wire. And I used a 35 ft piece of coax. No counterpoise, but if I use shorter coax, I would

[@stytzagatha]

let me know when and where to buy...i'll get one!

[@HAMRADIODUDE]

Check back next week for part two! I think Adam will discuss it being a kit or parts list... Thanks!

[@Machria23]

What radio is that, yaseu 897?

[@HAMRADIODUDE]

That is the Yaesu FT891. Nice and compact for portable use. I love ! Check back next week for part two! I think Adam will discuss it being a kit or parts list... Thanks!

[@brianumbrell4049]

Would buy one if offered.

[@rollandmason5596]

I would buy this or at least the unique board so I could build one. Looks very good. Thanks. KJ6DQ

[@johnwest7993]

Is saying 'dot' instead of 'point' for a decimal point a software programmers thing? Just curious.

[@stevensullivan3121]

I'm a retired ATC, we used point on air and Dot in the shop where things were built. Fair winds and following seas.

[@gerrykavanagh]

I say “dot” when its’s a separator, like in versioning, and “point” when its’s a decimal point.

[@radiotests]

Sure like to șee do a build on the for 3 and 10 😁

[@the_mad_swimbaiter455]

I'd buy a few

[@jamespurser357]

Count me in for one

[@mikemiles3068]

Good evening. KV5P

[@HAMRADIODUDE]

Good evening!

[@amnchode]

I shied away from his original kits, not because their quality (I want one... badly), I just DO NOT trust 'my' soldering skills, at least not that small. But this one, I might actually be able to build it.... So yeah, you could put me on the list

[@ronrico2620]

If he would ever start making kits again. Even pass the work off to someone else and work a deal. But I got tired of a waiting I got a box torroids, copper wire and the 3d printer running. If he can't sell a kit anymore I'll make my own antenna

[@HAMRADIODUDE]

You should be able to shoot Adam an email and ask him.. @K6ARK (i doubt that will tag him on here, but worth a shot LOL)

[@NgakpaW]

Sign me up.

[@HAMRADIODUDE]

Check back next week for part two! I think Adam will discuss it being a kit or parts list... Thanks!

[@ai5dd]

😂

[@berndkonemann5049]

Yop, would buy this right away. Well designed and indeed very compact. VA2VFF

[@HAMRADIODUDE]

Check back next week for part two! I think Adam will discuss it being a kit or parts list... Thanks!

[@daveswitzer1727]

100% will buy this. KO4UZU

[@zhenxinghan3611]

I’d like to buy one if Adam makes it available. DE N6HAN