Yay! One of my favorite guys building another one of my favorite guy's antennas. I'm stoked. I have the kit sitting in a bag waiting for my lazy keester to get her done...
Comme toujours une belle vidéo, pour souder les cms, je dispose, une goutte de cynao (prendre une cyano non instantanée) à l'emplacement du composant (avec la pointe d'une aiguille), je le colle, puis soudure etain, c'est plus facile !
Gil, I always enjoy your channel, and thanks for sharing your build of my kit! Yes, it's a bit on the extreme side of "small," but it's tailored for my super light SOTA activations. I have found that 49 to 1 or slightly less (3 to 20 turns ratio) is ideal with this toroid and build for a 40 m and up EFHW. 64 to 1 may work better for an 80 m antenna. Hope the matching unit works well for you. If you find SWR is high, check the resistive impedance with a NanoVNA or antenna analyzer. If it's below 50 ohms at resonance, consider removing a couple of turns from the secondary and testing again. TU ES 73 DE K6ARK
Just built mine last weekend. I thought I would have a problem with soldering the cap or winding the torrid. But no. Hardest part for me ? Getting the capacitor out of the little pack. lol After watching a few build vid's on this I actually did it a little differently. I found it was easier for me to solder the bnc jack first then solder the 3 connections of the toroid. I had plenty of room since one of the ground legs on the bnc connector was cracked and broke off on me.
I really like the K6ARK kit, and have built a few of them. I believe the heat shrink tubing you used was supposed to go on the optional inductor. The small section of shrink tubing is for the toroid. I have always made the kits 49:1 (for EFHW), and I used 26ga antenna wire. I look forward to seeing your results using 64:1. 73 - AA4K
Yep, this is correct. The small loading coil placed about 2m from the feed point helps optimize SWR on resonant multiple frequencies (i.e. 20m and 15m on a 40m EFHW wire).
Boy Sold OUT! thinking of this and a little qcx 20m kit. Good project for the girls. Also liking a book called "War Diaries: A radio Amateur in Kyiv". One of OH8STN subscribers pointed it out.
Yeah, that capacitor can be a challenge. I used the same technique you used...blue masking tape. I've built three of these kits that Adam (K6ARK) sells. The 9:1 is easier....no capacitor used. The kit you built is the 5 watt version. He also sells a 20 watt version. It has the original FT50-43 toroid and includes an FT82-43 toroid. The FT 50 is placed inside the FT82 and the two are wound as one toroid. I think you might be pleasantly surprised, as I was, how well they seem to work. Superb for minimal size unun. If you build one with the male BNC and wound as a 9:1, it can attach directly to the radio output Just some thoughts. 73 Karl K0TBT
I think when paired with a tr(u)SDR it will make a really good HF EDC radio kit so small and quite practical. Like you I built my own using larger a much bigger toroid but I want to be able to run up to 100W and so it's needed. I'm still thinking to have one of these for backup though. I think K6ARK used epoxy on his, whoch is what I thought you were going to do! 😀 Hot glue is just as good here I think.
Thanks for the review, Gil. I love everything EFHW, but this is just a little too fiddly for me. If I remember correctly the coax feeder to your radio works well as a counterpoise, anyway. 73 Marcus EA5HQ
I've since switched to 500v caps in the kits. This gives cushion for folks who briefly decide QRP means 50w when they're trying to eek out a contact. 😆 Realistically for QRP, 100v is enough.
@@K6ARK You have to be defensive. When I made up a 49:1 for an EFHW I used a silver mica cap, because I like tipping my hat to the old school ways! Do you use any particular dielectric?
@@Paul_VK3HN perhaps my reply didn't read the way I intended. There was no defensiveness in that comment back. My apologies. Truth be told, I've pushed 50 watts through my 20w kit trying to make a difficult contact work. And I know I've put more than 5 watts through my QRP kit in brief stints. I do these things too... In the end, all ceramic capacitors that size are similarly priced and it doesn't make much difference to me from a cost perspective so I went the conservative route. Silver mica caps are great for applications where you need consistent, reliable capacitance in a finely tuned circuit like a trap. If you got 'em, by all means use 'em.
@@K6ARK Ok Adam, maybe my comment wasn't clear, I meant to say that when you are offering up a kit that people are going to buy, build, use and occasionally abuse, you have to make conservative choices on some component ratings. All good. Looking forward to seeing your Pico Pixie progress!
13:57 I thought you were going to say “Epoxy!!” 😝😝😀 BTW, Giles, do you think (theoretically) that you may hear me with me transmitting from south of Toulouse on a ss990 radio on the (around 27,305 mhz) USB, through an inverted V antenna with 5m50cm each beam, linearly oriented axis some 25 degrees to the north? Also, where are the “French CB-stes ”??? I’m here since two decades now, as way back as 10 years ago, every night at around 7pm there were people on the CB arguing and insulting eachother. Nowadays there is no one, silence!! There are a few radioamateurs on the higher frequencies repeaters, also very stiff and selfimportant, but that’s all. Looking at how folks treat each other in UK for example, where does this trait come from (generalization, not all of course, not you! Though you have lived in the US) in the French psyche to insult one another, to hate one another, to despise, to envy, to be condescending, to try to act superior (while feeling utterly full of shame and complexes…), to act like a “petit caporal coincé”, where does this crap come from in people who otherwise have good hearts, but covered with this social mask thing?? I’m very curious and unable to find the root of this.
No idea where it came from, but I do not like it. My biggest gripe is people doing the cop's work for them, delation... Just remember, it's mostly unhappy people being assholes...
@@RadioPrepper Thank you enormously, you’d be surprised but this little word of advise brings a relief that humanity and old style “savoir vivre” still exist!
@@iw2epe if you go dowload the build instructions and read through them you will find your answer. Adam suggests 24 turns for an anyenna optimised towards the 40 and 80m bands and 19 turns for an optimized antenna towards the 20 and 10m bands (along with the optional inductor), and it does word really well. I use my k6ark efhw for sota activations and every time I activate I get chasers from Europe in my logs with only a 20w radio.
Hi, you can make any combination of impedance match, if you follow what was done, in this case 3 primary, with total 24, 24/3 = 8 8x8 = 64 to get 64:1 same with 49:1 using same principle 7 squared is 49 with 21 turns, hope this clarifies, n yes Gil has built dozens of hwef transformers
Mine works great. Got some crappy weak wire made in China, bought on eBay. But so far I haven’t broken it. So this antenna was tuned kinda droopy but works great. Made me a believer in end fed half waves! de n5vwn
Looks like a good piece of kit for those ultra small QRP radios.
Yay! One of my favorite guys building another one of my favorite guy's antennas. I'm stoked. I have the kit sitting in a bag waiting for my lazy keester to get her done...
Mine sat in a bag for months ;-)
Thank you. A learning opportunity. Phil - Suffolk. U.K.
Comme toujours une belle vidéo, pour souder les cms, je dispose, une goutte de cynao (prendre une cyano non instantanée) à l'emplacement du composant (avec la pointe d'une aiguille), je le colle, puis soudure etain, c'est plus facile !
Thank you for showing it. I just bought one a few weeks ago, and haven't had time for assembling yet.
Gil, I always enjoy your channel, and thanks for sharing your build of my kit! Yes, it's a bit on the extreme side of "small," but it's tailored for my super light SOTA activations.
I have found that 49 to 1 or slightly less (3 to 20 turns ratio) is ideal with this toroid and build for a 40 m and up EFHW. 64 to 1 may work better for an 80 m antenna.
Hope the matching unit works well for you. If you find SWR is high, check the resistive impedance with a NanoVNA or antenna analyzer. If it's below 50 ohms at resonance, consider removing a couple of turns from the secondary and testing again.
TU ES 73 DE K6ARK
Thank you Adam :-)
Hi Gil, nice to see another build video, BTW I recently recieved yr 64:1
Good to see you back. Thanks.
Just built mine last weekend. I thought I would have a problem with soldering the cap or winding the torrid. But no. Hardest part for me ? Getting the capacitor out of the little pack. lol After watching a few build vid's on this I actually did it a little differently. I found it was easier for me to solder the bnc jack first then solder the 3 connections of the toroid. I had plenty of room since one of the ground legs on the bnc connector was cracked and broke off on me.
Wow that thing is tiny. Thanks for sharing !
I really like the K6ARK kit, and have built a few of them. I believe the heat shrink tubing you used was supposed to go on the optional inductor. The small section of shrink tubing is for the toroid. I have always made the kits 49:1 (for EFHW), and I used 26ga antenna wire. I look forward to seeing your results using 64:1.
73 - AA4K
Yep, this is correct. The small loading coil placed about 2m from the feed point helps optimize SWR on resonant multiple frequencies (i.e. 20m and 15m on a 40m EFHW wire).
Wow, that's tiny. Great job!
Always great videos and I lost my cap and had to modify mine. 73 KV5P
Bult all the Unun's so far great video as usual good brother
Boy Sold OUT! thinking of this and a little qcx 20m kit. Good project for the girls.
Also liking a book called "War Diaries: A radio Amateur in Kyiv".
One of OH8STN subscribers pointed it out.
I'll check it out, thanks!
Looking forward to follow up on the end fed 1/2 wave kit.
Try not to burn your fingers ..
73
Yeah, that capacitor can be a challenge. I used the same technique you used...blue masking tape. I've built three of these kits that Adam (K6ARK) sells. The 9:1 is easier....no capacitor used. The kit you built is the 5 watt version. He also sells a 20 watt version. It has the original FT50-43 toroid and includes an FT82-43 toroid. The FT 50 is placed inside the FT82 and the two are wound as one toroid. I think you might be pleasantly surprised, as I was, how well they seem to work. Superb for minimal size unun. If you build one with the male BNC and wound as a 9:1, it can attach directly to the radio output Just some thoughts.
73
Karl K0TBT
Epic Gil, and great to see you back in the yacht
The surface mount cap seems a bit unnecessary. How much space would a standard cap of that size take up/weigh? A nice compact solution overall though.
I built one similar to the K6ARK design before he made his and put a small (non-surface mount) 2kv capacitor in the middle of the toroid.
I think when paired with a tr(u)SDR it will make a really good HF EDC radio kit so small and quite practical. Like you I built my own using larger a much bigger toroid but I want to be able to run up to 100W and so it's needed. I'm still thinking to have one of these for backup though. I think K6ARK used epoxy on his, whoch is what I thought you were going to do! 😀 Hot glue is just as good here I think.
Do not use epoxy. I potted two ununs in epoxy and they did not work, lost them both!
Thanks for the review, Gil. I love everything EFHW, but this is just a little too fiddly for me. If I remember correctly the coax feeder to your radio works well as a counterpoise, anyway. 73 Marcus EA5HQ
LOL. I wish I had a dime for every time I soldered something backwards or forgot to put something on a wire before soldering.
Why 1kV? What's a realistic RF peak voltage at the primary, assuming 5 watts?
I've since switched to 500v caps in the kits. This gives cushion for folks who briefly decide QRP means 50w when they're trying to eek out a contact. 😆
Realistically for QRP, 100v is enough.
@@K6ARK You have to be defensive. When I made up a 49:1 for an EFHW I used a silver mica cap, because I like tipping my hat to the old school ways! Do you use any particular dielectric?
@@Paul_VK3HN perhaps my reply didn't read the way I intended. There was no defensiveness in that comment back. My apologies.
Truth be told, I've pushed 50 watts through my 20w kit trying to make a difficult contact work. And I know I've put more than 5 watts through my QRP kit in brief stints. I do these things too...
In the end, all ceramic capacitors that size are similarly priced and it doesn't make much difference to me from a cost perspective so I went the conservative route. Silver mica caps are great for applications where you need consistent, reliable capacitance in a finely tuned circuit like a trap. If you got 'em, by all means use 'em.
@@K6ARK Ok Adam, maybe my comment wasn't clear, I meant to say that when you are offering up a kit that people are going to buy, build, use and occasionally abuse, you have to make conservative choices on some component ratings. All good. Looking forward to seeing your Pico Pixie progress!
@@Paul_VK3HN lol, no worries, I thought I had given the wrong impression in my response. Must be the language barrier 😉. 😆
Yes, I lost the capacitor! Does anyone have a product code number for a replacement, Thanks
Just use a 100pf 3KV.
13:57 I thought you were going to say “Epoxy!!” 😝😝😀
BTW, Giles, do you think (theoretically) that you may hear me with me transmitting from south of Toulouse on a ss990 radio on the (around 27,305 mhz) USB, through an inverted V antenna with 5m50cm each beam, linearly oriented axis some 25 degrees to the north?
Also, where are the “French CB-stes ”??? I’m here since two decades now, as way back as 10 years ago, every night at around 7pm there were people on the CB arguing and insulting eachother. Nowadays there is no one, silence!! There are a few radioamateurs on the higher frequencies repeaters, also very stiff and selfimportant, but that’s all. Looking at how folks treat each other in UK for example, where does this trait come from (generalization, not all of course, not you! Though you have lived in the US) in the French psyche to insult one another, to hate one another, to despise, to envy, to be condescending, to try to act superior (while feeling utterly full of shame and complexes…), to act like a “petit caporal coincé”, where does this crap come from in people who otherwise have good hearts, but covered with this social mask thing?? I’m very curious and unable to find the root of this.
No idea where it came from, but I do not like it. My biggest gripe is people doing the cop's work for them, delation... Just remember, it's mostly unhappy people being assholes...
@@RadioPrepper Thank you enormously, you’d be surprised but this little word of advise brings a relief that humanity and old style “savoir vivre” still exist!
You have the potential to be the next great Charles de Gaulle
You do know that a HALF WAVE end fed antenna is only a half wave on one frequency, right?
Of course!
You said 24 wraps, but the diagram shows 21 wraps.
21 is for a 49:1, 24 for a 64:1.
@@RadioPrepper Okay, but then you're not following the kit instructions. Let us know how it will work.
Right, but I've built dozens...
@@iw2epe if you go dowload the build instructions and read through them you will find your answer. Adam suggests 24 turns for an anyenna optimised towards the 40 and 80m bands and 19 turns for an optimized antenna towards the 20 and 10m bands (along with the optional inductor), and it does word really well. I use my k6ark efhw for sota activations and every time I activate I get chasers from Europe in my logs with only a 20w radio.
Hi, you can make any combination of impedance match, if you follow what was done, in this case 3 primary, with total 24, 24/3 = 8 8x8 = 64 to get 64:1 same with 49:1 using same principle 7 squared is 49 with 21 turns, hope this clarifies, n yes Gil has built dozens of hwef transformers
I can barely see pcb 🤣
Mine works great. Got some crappy weak wire made in China, bought on eBay. But so far I haven’t broken it. So this antenna was tuned kinda droopy but works great. Made me a believer in end fed half waves! de n5vwn