I built and tested a bunch of different EFHW couplers and yours ticks all the boxes for minimalistic QRP in outdoors. Your previous RU-vid video, in which you built the 1:81 transformer was really innovative, that's why I linked to it in my EFHW document. This kit makes it even easier to built this kind of versatile antenna and still allows to play with different radiator designs. Well done!
Very well done design improvement, Adam. This will make the build a lot easier than the old kits. You're an excellent teacher, Adam. Your explanations are very clear. 73 de AG7TX
Thank you for posting this video and sharing it with all of us! A few questions please: 1. Is there a place we can buy a fully assembled unit? 2. Do you have a variation where you have built SO239 instead of BNC? 3. Which specific wire would you use if you were building an 80 meter EFHW? That wire is long and I'm wondering if folks have a preferred wire that doesn't tangle and is easy to manage? 4. if you were going to have a multiband EFHW, would you use a 9:1 and a random wire? Or a 49:1 or 64:1 and a half wave wire? When going multiband with 80 m as the lowest band, which of those would be the better choice? Thanks in advance and I am of course subscribed with notifications turned on and thumbs up! 73 W3GUY
Hi Adam. Cool kit and nice video. Pleas make that tuning video. I have no problem building these things, but the tuning is always different than what I see on RU-vid. #73 - OZ4HJ
Everybody should buy and make one of these. Adam's channel has been a great inspiration to me. He is a great teacher and very innovative. I have made several items based on his videos and been very successful in the QRP arena. Amateur radio operators need to support people in our hobby like Adam. Thanks for this video and I just placed my order. Well done! KJ7PRS
So hypothetically speaking if someone were building this matching unit and their three year old walked off with the magnet wire and that someone searched the entire house for it but couldn't find it, what would you recommend as a replacement, would any magnet wire work, specific gauge, enamel type, etc? Thanks for any info, it would be helpful if this hypothetical situation were to happen. You mentioned Remington industries in your live stream with HRCC, but they have quite the assortment.
@@K6ARK Awesome thanks! Will do I also noticed that the affiliate links in this video description show as unavailable but there is a kit with your name on it with the female connector available on amazon is that just a new link of your or a copy cat. I will send the links I have found in the email
@@nehem11e yeah, it's a long story, but basically Amazon let someone else hijack my original listings because I didn't have a registered "brand". I had to create new ones.
I screwed something up. I cant tell what. Maybe I'll start over with a new one. The only thing I noticed is that I bridged the CP to GND pad when soldering the coax connector on.
Charles, the most common failure is not removing enough enamel from the magnet wire. Check for continuity between the BNC center pin, the antenna wire, and the BNC ground. Three should be close to 0 Ohms Resistance between them. If that's not the issue, feel free to send me an email with some close up photos of your build. Remove the external heat shrink if you installed it already. Try to get a few different angles so I can see which windings are connected to which pads. I'm always happy to send some spare parts if you do end up needing to rebuild.
HNY everyone. Thanks Adam for sharing and making your design available for everyone who wants to have a go at making an antenna. Hope to hear some dx cool waves from summits in 2022 as bands pick up. Regards Ian vk5cz ..
Nice Kit. Looks like Type 43 toroid which worked well for me with 49:1 transformer EFHW. Type 2 (Red) toroid was better for me as I got better performance with 9:1 UnUn, specifically 10m and 6m on NET Nights which I do portable at times ; ) Anyway a must have in my portable setup . How much power will it handle? Thank You. . . Mostly I use T200 Type 2 (RED Toroid) 9:1 UnUn, Type 43 RF Choke, 29ft wire and 17ft counterpoise (EARCHI Antenna)
Yes, it's a -43 mix which works well in all 3 build options. I generally recommend a maximum of 10 watts for lighter duty-cycle modes and 5 watts for modes like FT8.
Yes! I have more kits inbound to Amazon tomorrow. Feel free to email me (QRZ address is good) and I can likely get what you need sent direct as I plan to make a post office visit tomorrow as well.
I just built the EFHW version with female BNC, ready to tune the wire but don't see your video you mentioned (to tune the antenna length) at the last of this one. I guess I can experiment, someone below said 61 feet but I'll start with 68 or so. I did test it out (using the internal tuner and about 50 feet of wire) and got a weak signal report on 7.255 with my G90 on five watts. What is the max power recommended with the EFHW?
Start with a bit more than half a wavelength on the desired frequency of operation and fold back the end of trim to resonance using an analyzer, or trim to minimize SWR if you don't have an analyzer. The standard build is good for 5w on heavy duty cycle modes and 10w of lighter duty cycle like typical SSB.
Yes, it's possible to build as a 4:1 for an OCF dipole. I've done it, and others have too. You don't need a common mode choke, but it can help reduce noise if you're in a high noise environment (uncommon when you're out portable).
Vitor, it has been challenging to keep up with demand, but I have more inbound to Amazon as of today, including male and female QRP kits, and new 20w kits with an additional, larger toroid, longer magnet wire, and larger heat shrink. They should be in stock again soon!
Nice kit, mine is on the way. I might suggest putting in one or two extra spare capacitors. Those SMD caps are about 10-12 cents purchased in 100 quantity or greater. People are definitely going to lose the cap, burn it with the soldering iron, etc during installation, and it would be a bummer to ruin the whole kit over that one part. I say this completely acknowledging that you've made it as easy as possible with the nice little custom PCB. Nice work.
Good call, maybe worth it. I am also happy to send a spare (they're so small they fit in a regular mailing envelope) if someone damages or loses the one in the kit. Just reach out to me and I'll be happy to help.
Hello Adam, quick question regarding the mini microphone kit for the truSDX. Are you still producing them? Can’t find them on Amazon. Thanks Roger W8RLP
I produce kits when I have time. I work a lot at a day job and volunteer for SAR among other things, so my free time is limited. I try to balance it across preparing antenna kits, mic kits, and winders, and then of course doing an occasional fun thing for myself like a SOTA activation or backpacking trip. You can always build your own from the files on Printables and the bill of materials posted there. Link to it from K6ARK.com
I BUILT up mine this afternoon. Wonderful. It really works. Endx halfwave antennas are great. I have experiences with Fuchs antennas. You only need a short counter poise ore even none. That's the advantage of these kind of antennas. I like that antennas.
Hi Adam, impressed by the size and simplicity of the design. Even for me it seems to be feasible to build the kit. Unfortunately it seems to be sold out. Do you have an idea by when this will become available again (in Europe)? 73 ON3STG Gert
There's nothing wrong with that at all. You can always just cut off the stub if you never use it. Be sure to follow the written instructions. They are a little different than the board that I was using in the video.
My favorite portable antenna wire is Poly Stealth. I like 26 ga for the smaller kits, and although 26 ga will also work with 100w, I like 22 ga for the nicer handling characteristics.
This may seem like a dumb question but should there be a closed circuit between the BNC center conductor and the four lugs? I guess there's a DC circuit though the secondary winding. It's ok at RF?
Ok I got one. Hot dang, it works! I screwed up and tried to save money buying Chinese wire instead of ‘wireman’ silky wire. So I tuned it to be droopy so as not to stress out the cheap wire. Still works! Added a piece of 20’ coax. Still good on 20 and 40 meters. This is great!
Adam would love to see a short video on wrapping the 9:1, i have read your instructions over several times, but would still love to see it done, being from Missouri, Show me 😊
Just finished my EFHF Build. Total finished length 61.5'. Flat 1:1 SWR across 40, 20, 15 and a good chunk of 10. No Coax - direct to radio. My tip: I placed a loop of paracord thru the small loading coil and use that as my lash point on the radio end.... the 6' of wire between that and the BNC are then 'loose' for connection to the radio. Thanks Adam!
Not at this point, but I will likely put together a ~35 w max version targeted at KX3 and G-90 users. I'll think about design options for a 100 w option, but it will require some significant design changes including a much larger toroid.
Hi! I've been trying to figureout what's the specs of these thin wires you use for the antennas. I saw this in your amazon sotre: "YXQ Yellow PVC Coated Tin Plated Copper Wrapping Wire Wrap 305M 30AWG Cable Reel" Is that the wire you use for EFHW, etc?
That 30 ga wrapping wire is super cheap stuff that's nice to have around for experiments, and I've even used it for some UL portable antennas that I have used for years, but it's not what I'd recommend for a solid build. The BEST portable antenna wire, IMHO, is Poly Stealth 26 ga wire from Davis RF. It's copper clad steel with a nylon jacket. It's strong and small. But it's also not particularly cheap at 29 cents/foot, plus shipping. So I have been using a PTFE insulated stranded copper wire in 26 and 28 ga that I buy in bulk from China. It's cheap and works well, but it's still not poly stealth. If you want to try some out, email me (good on QRZ) and I'll get some sent your way for a reasonable price. Hope that helps!
Yes, they do. If you damage more than one lug, let me know and I'll get you a new BNC and updated PCB that fits better. Or, if you just want the PCB before building the kit so you don't have to bend them, I'll be happy to send one. All future kits will have the updated PCB specifically designed to fit the female BNC rather than the generic male one.
My SOTA activity (and video production) has taken a back seat to other projects including putting together antenna kits for all of you. I've also been more busy with SAR training lately. I'll get back to it all for sure. Got a couple of activations in last weekend. 🤘😁👍
@@K6ARK I'll have to checkout the antennas. Cool that you got some activations, I need to get out and do that also once I get radio issues resolved. Lots of respect on the SAR! Cheers KJ7SHW
@@K6ARK Adam, I ordered one of your kits, looking to make a segmented version covering 80/40/20. Could you let me know what extra parts I will need please, or if it's even doable, lol. Cheers, and thanks again for your videos. K1AMT (new vanity call sign approved :-))
I don't have a video on tuning, but there is some basic info in the instructions that should help. Beyond that, the tuning process is typical/standard for an EFHW.
Hi Adam, great kit and great video. I recommend one additional step before soldering the BNC: Do a continuity test to check that the enamel has actually burned off. Desoldering and resoldering the toroid after the BNC is in place is a real bear-I learned the hard way, 😂
Thank you for providing the kit! I just ordered one! I never got around to buying the components myself to try and build it back when you had your video of how to build them. So glad you put this kit together. Juddie - WD8WV
I built the 9:1 version today. Messed up the toroid winding! But found 3 colors of same sized wire and wound 3 separate windings. Colors made connecting them easy. With 29 ft element and 17 ft counterpoise tuned nicely and had 3 POTA hunter QSOs on 40, 30 and 20 at 5 watts CW. Got good reports. Thanks for good kit!
Hi There! Greetings from UK. Great video and really happy to learn you came up with a way to make your design available to purchase. First time I saw you build one I said to myself I will struggle with the tiny capacitor directly to the BNC. This KIT makes everything easier. Thanks.
@K6ARK Portable Radio i bought a kit after watching the HRCC build stream, looking forward to putting it together. I was looking for any info on tuning for EFHW build, I don't see any specific titles, can you point me in the right direction?
Your best bet right now is to review the text instructions. It briefly describes multiple ways to finish the antenna. If you have specific questions after that, fire me an email at k6arkportableradio@gmail.com
I did the 9:1 build but used some cheap 26awg it's a big difference compared to the polystealth that comes with the kit... My question is can just use 14awg stranded wire I have plenty of that
I ordered before even starting the video. Built the original version for 20m and gave it to a friend for their QCX. Will build this one for 17m for my QCXmini. Congrats on the kit release. I’ve missed your videos.
Are these coming back in stock soon? I'd really like to get one. If not, I have the pcb-mount bnc, the toroids, capacitors, and everything else, just don't have the PCB. Not opposed to making my own if you'd be so kind as to share the PCB design, or if you have another PCB lying around you could ship me so I can finish this antenna. Attempting my first SOTA this Spring, and would really love to take this along, and promote you as well.
Yes, I just dropped off another batch at the post office, however, if you already have all the other parts, I'd be happy to just send you a few PCBs. Email me direct with an address and I'll drop a few in the mail for you.
I see they are back in stock. I just bought two as a way of saying thanks for all your help. I going to build some from scratch as well. Were do you source your antenna winders? Appreciate your work.
Hi Adam - thank you so much for your channel which is full of great information! Do you have any plans to "recharge" Amazon (or any other outlet) with these little kits? Thanks!
Yes, I restock as often as I'm able. I am sending another batch of QRP kits tomorrow but they'll sell out fast. Sorry for the delays - the antenna kits are not my day job and my family, regular work, and SAR volunteer work takes priority. Lately, they have been consuming almost all of my free time. Thanks for your patience, and check back on Amazon over the next few days if you're looking for a QRP kit. More 100w kits after I get back from Dayton...
Hey Adam, great video! Curious if you have a recommendation for a multimeter? I don't have one yet and seem to run into more and more uses for one. There are a ton out there and $ to $$$. Thanks!
I generally recommend 10 watts Max for lower duty cycle modes, and 5 Watts Max for heavy duty cycle applications like ft8. I would expect typical CW operation at 10 watts to be just fine.
You can see if Amazon will allow you to order and ship to the UK. If not, you can contact me and I can ship direct, but a batch order is likely necessary to make it worth it. Shipping starts at around $18-20 US but is the same for up to 4 or 5 kits because they're relatively small and light.
Is it bad to run the ant wire through the middle of the torroid for the EFHW config? Also, is the other heat shrink that is included in this kit just for fun?
It's fine to send the wire out the center of the toroid. The extra heat shrink and plastic tube is to make a loading coil to help with tuning on the higher bands as explained in the instructions.
Nicely done Adam, IMHO this is one of your best build videos. I built a version of this antenna based on your previous vidios and couldn't be happier with it. It bagged me my first SOTA DX in to Guadalajara Mexico. Keep up the great work/content Adam. 73
Please follow the written directions as the build process has been modified a bit. The updated toroid winding method is a little easier and the boards were updated to accommodate for additional build options.
