Ham Radio experiment - End fed half wave antenna sloper vs flat horizontal orientation.
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- เผยแพร่เมื่อ 25 มิ.ย. 2024
- I'm not an antenna expert, I'm just sharing my observations and my own speculation. Learning more about the end fed half wave antenna with an experiment.
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Cool comparison. I love how quiet your location is - you're the envy of everyone here!!
A noise floor of zero - amazing! Even if I turn off my main breakers and run on batteries at night (like I often do), I still have an S3 to S5 noise floor.
Neighbors... :-)
Kevin, this is great! I so appreciate your experimental mindset, your transparency with the good and bad, and your plain-language explanation of how/why things are working! Thank you. 73
i have watched this a couple times over past year and it has helped me better understand and config my flat horizontal end-fed. thanks Kevin
Thank you for the informative content. I built one of these last night and was pleased with the results.
Interesting results Kevin, thanks for sharing.
Excellent video, well done Kevin... brand new Ham here putting up my first EFHW.... appreciate all the tips! KK7TPQ 73
Yes, that was some good stuff. I have an end fed that I have not put up yet, so this helps out. Thanks Kevin.
Hi Kevin. I am running a home made 3 Band EFHW since 2 days now as a portable setup. I was using it as a sloper configuration, worked well so far. Never tried it as a vertical setup before but I want to try this on another day may be.. Nice to have a look at your experiences. Keep up good work. 73's de Uncle Günter
Another great efhw vid 🙌
Thanks for the video. This is an interesting test to see. I use both dipoles, and end-feds, normally my thought process is, if I am able to suspend a center with coax, then I hang a dipole, if not I use an end-fed. So after seeing this video, I have another option.
Hi Kevin,
Nice that WSPR showed a definite pattern change with the antenna orientation. Would not have expected the upward change in resonate point. Good info. I have all the aluminum tubing needed for a vertical 40m EFHW. Just waiting for warmer weather and softer ground to pound in the galvanized support pipe. Stay safe. WJ3U
Thanks Kevin! I built my own 80m EFHW and have been moving it around horizontally and vertically. It's pretty versatile!
what which sounds better?
Interesting video and a hell of great info. Thank you Kevin!
Look at that noise floor! I ran an errand yesterday and mine was only S9! Thanks for the post.
Nice informative video OM Kevin. I am also experimenting with a 8010 EFHW .
Interesting. I recently have become interested in EFHW antennas for portable use. Al of your discovery makes sense just surprising to see the theory is correct. Haha. I hope you are doing well and are enjoying life down in the desert. Oh we have started looking at RV’s and I use your setup as an example for a rolling ham shack. All the best!
Interesting test Kevin making for a good video 👍👏👏
I have two end fed have wave multi band antennas. My first one was the 8010 set up as a sloper. Transformer mounted about 4ft and allowing upward to scout 40ft. It did pretty good. Now I have it on a push-up mast at 20ft sloping across and up to 35ft. Pointed NE/Sw. also have a 4010 mounted at 40ft at both ends pointed NW/SE. works much better. SWR is much lower , I am now able to pick up the weaker stations much better, much better for DX.
Great video. I have 2 10-80 EFHW in flat top configuration. They are oriented N-S and E-W and set by a antenna switch to my transceivers. I haven’t noticed that much directionality as expect, especially on 40 and 80 meters de WA9SWW
Thanks for the video, I will have to try it with my end fed.
Interesting comparison. Thanks for your work. 73 from DL
Excellent! Thanks for the tutorial.
Very informative video!
Very cool information. Thank you
Very interesting! Thank you and I'm going to do that with my 20m End Fed homebrew atenna as soon as it stops raining! 73 de N4CVX
I am pretty sure Steve Ellington did this comparison too, as well as testing all manner of grounding and counterpoise configurations. I think he determined deploying the antenna in a sloping manner performed the worst of all tested configurations (which is to say worse for the EFHW), and if I recall correctly, the inverted L performed the best. I have the Steve Ellington "special" deployed south to north at 30' at the feedpoint, but since my back yard drops off significantly, the majority of the 134' wire is at about 50' in height. My Reverse Beacon Network testing and contacts show results just like yours. Contacts due south and north are rare.
Great video - very interesting!!
Good video, very interesting!
I have also wondered about this. I have also wondered about the foot print of my current EFHW thats horizontal but about half way down the wire it makes a 90 deg turn at my property line.
Very good video thanks for your time nice job well done from Gary 73.
Interesting you mentioned a nearby inverter. I found my Mitshubishi mini split inverter a noise source . Power line filtering has eliminated most but not all the noise.
Add HVAC INVERTER SYSTEMS to the list of usuall suspects.
Thanks!
Well done 👏 ✔️
I'm a full-time RVer and lucky to be able to put up an HF antenna in RV parks...some parks worse than HOA's ..... by the way, I also have a buddistick vertical with 5 ground radials and many times it does better than my endfed dipole 73/k6sdw
I'm a full-time RVer too, parked north of Phoenix AZ. My main solution is a 2m mag-loop, but I just wish I had a noise floor as low as Kevin's.
thanks. very good.
great video, thanks for sharing, 73 from Chile CE4UGI
Enjoyed the video Kevin. Can you let us know if in either configuration, sloper or flat-top if you grounded the shield side at the feedpoint? Thank you & 73 //KK0DJ
Always run EFHW's as inverted V's QRP. Was wondering what happened to them as horizontals. Thanks for the video. 73's
Great video man.
I'm jealous of your noise floor man.
Keep on keeping on
🤣 ROTFLMFAO... Dude you are hilarious, no doubt about it.
You are also 100% correct, the figure 8 is the best and most efficient way to wind your EFHW. Keep up the great work/content 73
My end fed half wave has the transformer end at about 25' and the distant end at 10-12' in a straight line east-west. It's a MyAntennas 8010. I put it up without tuning at all and had acceptable SWR using a tuner in places. Just recently I folded back about 15" off the distant end to get resonance on 80 meters at 3.56 MHz or so. SWR on 20 meters is pretty well flat across the band. Still checking out the performance, but it seems to do the job for me. I have been working FT8 and having lots of fun doing it. Thanks for sharing your experimentations.
Hi Kev and William.. Sorry if this is a ‘silly’ question with an obvious answer, but when you fold back the end of (say) an EFHW, does that have the same effect on the SWR as completely removing the folded back length? Hope that makes sense🤔
Thank you..
@@johnrees44..G4EIJ I replied, but it has not shown up yet and then I realized I didn't really answer your question. I would say that cutting the antenna and folding the antenna wire back on itself would be very close to the same as far as performance goes. The difference would be pretty minor, but it would take some accurate measurements to determine.
@@billpowell5931 Thank you..It would be useful if the amount of cable folded back to tune the antenna was equal to the amount I would need trim from the cable to achieve resonance.. I always worry about trimming too much😩..
Time for an experiment, maybe😊..73
Whoa, William Powell your one of my favorite actors! ;)
Why is a narrow dip on the swr more efficient than a wider curve you spoke about?
Thanks
Hi!) What about putting antenna's wire down from hight? Must be not a best idea?)
Looks like you got a lot more gain with the second set-up. Question. Have you already used or looked at using an Inverted L antenna? I'm a nubby so I'm looking for some advice on that configuration also. Thank You in advance.
An inverted L will give you some of the advantage of a vertical and some of the advantages of a horizontal antenna, but not the 'best' of either.
It's a really popular configuration and it does work pretty well.
When you raised the feedpoint up did you drape the counterpoise on your roof??
I'm in Pahrump Nevada. Where are you located? Thanks for sharing 🍸. Love the channel.
In SW Arizona at the moment. Thanks!
Excellent video, Kevin. I just got an x6100, which is perfect because I always work hundreds of miles from home, and now I'll be able to play. If I use an EFHW with a wire cut for 40 meters, will it resonate on 20 and 10 too?
The answer is yes, but it does depend on where it is cut for 40 m. If you have it resonating at 7.2 megahertz, then it will resonate at 14.4, which is double and above the 20 m band, and it will resonate at 28.8. so you might want to resonate it at 7.1 so it will then be resonant at 14.2 and 28.4. It's all about the harmonics
t would be nice to see how a sloper off of the ground works. just add another 22ft to one end. I'm building a vertical sloping co-phase with directors and reflectors for 10-12M, so, 6 vertical elements in total on magnetic mounts around 27ft apart these on a large tin roof with 11 to 12 degrees pitch facing mostly west from Europe. Last week i reached Sao Paulo in Brazil on 100W with just one mag mount on this roof, i will swap for 6x adjustable whips, there are some nice extendable antenna available that extend to over 5M long there is also a cheaper option that extends to 2.5M which might serve for the directors and possibly the driven elements if i add a little to the tops but i imagine the larger version will be able to handle slightly more power.
Couldn't tell how tall those trees were nearby, but if they are taller than your masts you might get a light line up with your mini and a downrigger clip. There are lots of videos on using the mini to carry fishing lines out that would work with similar application. Gonna try it with mine soon.
The trees here rarely get over 15 feet. I plan on experimenting with the drone if I get to northern AZ this summer with big pine trees.
Good morning Hoosier. .. ... ..
Thanks Kevin, Out of curiosity, what if you fed the sloper from the top instead of the bottom? I believe it would change your take off angle, but would it change the reception?
Anything that changes the angle of the strongest lobe during transmission should also change the sensitivity in the same way, I think. I'm pretty sure an antennas pattern of sensitivity for RX is going to mirror it's pattern of radiation during TX.
Always wanted to know what the result would be if the feed end was mounted at the high end. A sloper with the feed end high. They say a quarter wave sloper with the feed high had the current max near the ground therefore not so good, however, a half wave should perform ok. Hmmmm?🤔
I live in HOA so I can't have an antenna so I decided to make an inverted V and use the peak of my house and put a balun up there and it did not work because I couldn't get it away from my house far enough, it wants to be in free space. So I just made a sloper from the peak of my house heading West. it's 14 ft high at the top, Center fed and 27 in. off the ground at the bottom of the slope and that is pointing west. Andy2 cb set to 1.75 watts to a RM kl 203p . Our best contacts from Hawaii, Bahamas... I'm in south Nevada , we're getting skip from Tennessee, Florida, Georgia,Illinois ,DC, Michigan, Alabama. Best part is I cover most of my town ground contacts. Works great for dx and local. I'll never go back.
Now can you do the L vs the V? I noted the 2hr time difference between switching which allowed Grey line to move in changing things. I’ve had great luck with these antennas H. Higher bands seemed to play better than it being in the L form. Maybe something with my ground ? I test for about 3-7 days per config. I know the maximum current of these antennas is smack in the middle. I wonder if that affected the antenna on say 10-20m in the L config. I do seem to notice better results with it sloping at a 45. But overall the flat top has impressed me the most. Mostly Nvis with some dx per the usual dipole below 65 ft agl. Thanks for posting your results. I’m curious as how the inv V fits into this as well as the L in the desert. 73
There's a way to test both at exactly the same time. Maybe Kevin will do a video on that.
Thank you very much for the interesting video.
It would be interesting to test what would be the influence on the direction if you would put it much closer to the floor.
73 de Roman, HB9XBK
If you get it lower than 1/4 wavelength and keep it flat, it will begin to push more of the energy upwards, decreasing skip distance. Becoming more NVIS.
Hey Kevin, hope all is well in your world
Jeff de WD8JM
I wonder what you would get if you set upon a flat horizontal L covering all sides. Bend the wire 90 degrees at the center. You could even run the wire out to 203 feet and use more coax before the choke. Inquiring minds want to know. I might try this experiment based on your results.
I have an end-fed that I have running in a kinda inverted-v shape, except it's horizontal. Seems to work well in all directions
I've got an 80m EFHW that is up 25 feet and about midway there is a support ring dropped down from an over hanging high branch, I raised that midpoint up a bit. Curious, what is the angle of your inverted v?
I'm running east/ west to cover the east coast region and located in Raleigh NC
Kevin, have you tried vertical to 40+ feet then flat for remainder of the wire? My EFHW is an 80m-10m, 163 feet of wire, that goes vertical up to 43 feet then horizontal (oriented east to west) for the remainder of the wire still up at 40 feet.
That would be what they call an inverted L antenna. Not uncommon, and I've used it previously. Works pretty well.
These sorts of questions are why I'm learning to use EZNEC. I'm hoping it will be easier and more dispositive than endless experimentation of configurations (not that there's anything wrong with that).
That would certainly save time. I just like fiddling with stuff physically.
I love your videos!
What would the result be if you ran flat top with right angle bend in the middle 1/2 & 1/2?
Assuming you're talking about that right angle being a bend in the vertical direction, that's pretty much an 'Inverted L' antenna. And yes, it would act both like a vertical and horizontally polarized antenna.
@@loughkb actually I was wondering about a bend horizontally to make it fit in my Lot. flat horizontally with a right angle bend. or slight slope from center
@@MYtimeNspace The less of a bend the better, but you're ok up to 90 degrees. You just need to make sure the antenna doesn't bend back on itself at all.
Ah hah and I was cautioned I have a certain vertical fan dipole mounted on my deck that's why even after careful measuring of the elements the tune is not spot on the elevation though not that great does change the tune
Wondering if running the endfed as an inverted V with the apex up at about 30 ft would have similar results as the sloper.
It should probably be very similar. Not as omni-directional as a vertical, but much more-so than a flat dipole.
MMANA-GAL is your (free!) friend for answering exactly that question.
Just a question, what would happen if you were to put this antenna 6' above the ground in a square or Octagon configuration?
Not a lot, except maybe some disgruntled worms.
Would this test be relevant for random wire 9:1s as well?
I suspect so.
My QTH is S9 floor. So my random wire is relatively useless. City dwelling sucks for ham!
Try a different specific length antenna. I'm running an EFHW 132' with a 49:1 transformer and it works great. 50' up in a horizontal configuration. These can be noisy antennas. have to take care of rf on the shield by grounding shield before entering the house. I'm in the city also.
100 Watts into a Vacuum variable capacitor Mag loop with digi modes or CW.
Lucky to get 5 watts ERP, on 40 meters. Making QSOs, 5000 miles out.
Ham station on a tiny city balcony.
I have the same issue on my endfed. I plan to put up a closed loop since those seem more immune noise.
Thankyou Kevin! As HAM radio newbie I started building a loop antenna. Based on your loop antenna! The MLA works great and now a try Theo Oskam replace the DC gear mottbh a stepper motor and auto tune the MLA.
Kevin, in this yt you are using AN nanovna, whatsapp brand is this equipment?
Thx. Theo 73
PA0HTY
I'm also building a magnetic loop antenna with auto tuner, so I'm interested in your project. How's your build going so far?
It's a blue VNA. Search my channel for that, you'll find the video I did on it.
I live in the NE null, no stations, on internet.
What antenna analyzer do you use?
I have a BlueVNA
So close to a doublet but getting feed point high up is good. Think open spaced feed line would help sum 😉KC3ONO hope to hear you try to check in to the Toad Harbor Net 1.930
The 49:1 match is designed to work with 50 ohm feeder and required to feed the resonant wire at the end where it's characteristic impedance is just shy of 2.5K ohms. This makes an End Fed Half Wave (EFHW) wire antenna.
Anything else would be a different antenna. :-)
Smacked a couple degenerate posts for you..
So daylight is bringing the tees n jeans .. nice to hear. Keep up the good reports,
I just killed three of those comments with garbled links to adult crap. I report them. But like cutting a head off the Hydra, they just keep making more fake accounts and spamming on. They're peppering just about every new video now.
My flat EFHW is great for NVIS, not much more. Inverted L much better longer distances and omni. Best "counterpoise" is about 20' of coax with a CMC then on to shack.
Inverted L will radiates omnidirectional from vertical part and like dipol from horizontal part. My best setup for EFHW. Oh, plus 0.05wl of counterpoise
Looks like his testing with WSPR as a flat top proves it's not just good for NVIS to reach the central and eastern US as opposed to NVIS with normal prop just a few hundred miles.
I have seen .005 wavelength as a length for the counterpoise.
You have one 0 extra after the decimal point.
That’s .05. Or 1/20th as I heard a math challenged man say.
From trial and error that seems to work very well.
Lots of people think Asia is "west" and Europe is "east", because the Mercator projection lies! Hams with omni-directional antenna patterns don't care, that's understandable.
When you get directional, it sure matters.
What continent is at bearing 090? What continent is at 270? It's interesting to look up (and print) a customized Equidistant Azimuthal map (or simply use that option in PSKReporter).
(Answers: Africa and Australia, respectively... for me in the northern Rockies. YMMV).
Anyone know why this TH-cam Video doesn't play after I clicked the Normal notifications it opens TH-cam App and just shows a Black Screen with the message, This Can't be played in the background.?
There's nothing unique about this video. It's in the same format as all the others.
By counterpoise, do you mean a length of wire mounted to the ground lug?
The ground side of the transformer, where the coax shield connects to it.
@@loughkb I have a store bought end fed. It had a ground lug/screw on it. I’ve never opened it so I wouldn’t know what the grounds side of it would be. It doesn’t open, it’s sealed.
That screw is almost certainly connected to the shield side of the coax connector and would be where you'd connect your counterpoise.
How high was your wire when horizontal?
I think I remember that it was 25 ft. I thought I mentioned that in the video.
@@loughkb you may have and I just missed it. Thanks
Kevin - Please make your scope output oscillographic
Very interesting. Excuse me while I go move my end fed around..........KD9PDE
What about an end fed in an inverted V or inverted L configuration? Maybe a top-fed sloper? 🤔
It'll behave similar to a center fed dipole in those configurations.
@@loughkb oooh, so it would be more directional than a sloper configuration?
@@MuffintopBikini Both the inverted L and the inverted V are more omni-directional, closer to a vertical in the pattern.
A dipole antenna is a dipole antenna no matter how it is or where it is fed The pattern does not change. Ron W4BIN
Except for ONE major advantage of an end-fed half-wave: The second harmonic is available and usable. Ref: The numerous 80-10 end-fed half-wave antenna designs.
Personal request for inverted V test! =)
It would be more omni-directional, that's about it.
@@loughkb I was wondering more about close in contacts, since it appeared you had a large skip zone around your QTH?
@@YZFoFittie An inverted V will provide a sort of middle ground between a flat top and a vertical. You'll get a bit of NVIS effect and a bit of lower take off angle. It kind of splits the difference, some of each but not as good as each.
Good explanation and very informative. Thank You. 73 vu3tbu
The Canadian phone band starts at 14.110. it's super annoying when it gets loaded with CW or digital modes. I guess no one checks the band plans for neighbouring countries.
You using a 16:1 UNUN.
No, the common 49:1 design, as I mentioned.
Radio waves come down from the sky, the end point on a dipole antenna is irrevelant to how the antenna hears because radio signals are coming down from the sky. Your theory only applies to ground waves.
Radio waves come in from all angles depending on the layer of the ionosphere they bounce off and how far away the station is. We're on the surface of a rough sphere. Draw a straight line that touches the edge of a sphere and now look closely at the 1-2 degree arc where the line intersects the edge of the sphere. As you move through that section, the angle of the line relative to the surface of the sphere will change over the area.
@@loughkb could you please say that again in simple english so I can understand, I don't know what a sphere is and can't quite visualize what your trying to say. Make a video using a chalk board and visually explain your theory and I will watch it.
@@hamradiolife9854 A sphere is a ball shape. Our planet is a big ball. Signals come down from the sky at all angles, depending on where they are transmitted from.
@@loughkb Ok 👌I see what your trying to explain, but for a radio wave to come down from the sky at what ever angle and only barely excite the very end point on the tip my dipole antenna the radio wave would have to be more like a lazer beam than an actual ocillating radio wave. Your theory would only be correct if the radio wave was at a frequency so high that the radio wave itself had a wave length of miniscule porportions resembling a lazer beam.
Thanks