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Scrap the Traps 80-Meter EFHW Experiment

Created by N2RRA on 2020-03-26

LOL, so here we go. I know how some articles will and can potentially turn into a circus of critiques, comments and opinions, but this is too encourage and remove doubt in the minds of hams with restricted living arrangements that didn’t think it was possible also even maybe defying all the antenna computer modeled information. Keep in mind that I’m so dumb I can’t peel a banana so if I can make this happen so can anyone. I need too mention that I never thought of an End Fed Dipole as an antenna that would work well. I’ve built many of all variety’s of antennas, but never an end fed and never a balun. This also was my very first balun ever built.

 

We all read and are told certain antennas will only work effectively if installed over true earth ground and oriented a certain way. We are told of R.F. patterns depending on orientation and the directivity we are too expect. So we then begin to envision our home surroundings and how can we install an antenna that most can not install as in a 80m half wave antenna the likes of 131 feet in length for example the way it should be installed. Then we tell ourselves, it’s not gonna work cause it won’t be over true earth ground to take advantage of deflection, low loss’s, the direction we want, or metal objects like fences and sheds also that may become a problem or other. What happens? Those people are discouraged to even try. They don’t try cause they think only inside the box by what they have read, or were told. Even though technically all the R.F. data may be accurate it may not be all that correct on what some have mentioned in the past on what will work, or not work well. Here’s my experience hoping it gives motivation for those who didn’t think it was possible.

 

Below is a photo of my QTH. As you can see I fit a full sized 80m EFHW (End Fed half wave) antenna measured at 130ft. with the general thinking of getting as much sloped at a straight angle.

 

(18ga. Antenna wire in red. Balun and counterpoise in green. Wire does hit and lay on edge of garage roof before laying on house pitched roof.)

IMG_2016.jpeg

 

Unfortunately, that short length of approximately 7 feet sloped into the tree was too keep high enough to clear walking around it before slopping into the air, allow the 7ft. Length of elevated counterpoise to be ran straight out and in the clear of objects, because had I placed the end closets to the corner of the property it would be surrounded by another home, that pine tree and metal shed courtesy of my neighbor. Where it starts is the best chance at being in the clear and taking advantage of true earth ground. Maybe I would’ve been better off running it through the tree and taking chances at lost R.F. into surrounding objects, but I’m good with it. If some are wondering why not run a dipole between the trees East and West it’s because there’s only 88ft of space. I have ran an 88ft. dipole and a design that resembles a half square 66ft. long for 40meters, but I think the 80m EFHW is much better than any of those so far.

 

So here’s the run down at the type of end fed. It is all home brewed. A home brewed 49:1 balun made of duel core (2) FT-240-43 terroids wound with 14ga. solid enamel wire, 100pf 15kv capacitors, 18ga. stranded bell wire for stealth into a home brewed electrical housing vented to keep the cores cooled when I wanna run a Kilowatt mounted on a PVC pole 7 feet above the ground. The 7ft. Elevated counterpoise (green in photo) is also 7 feet off the ground horizontally. This was my first time in 30 years at building a balun. Built many antennas of all kinds, but never a balun, or an end fed. Below is a photo.

IMG_2121.jpeg

IMG_2122.jpeg

 

Results on my MFJ Analyzer weren’t what I hoped for and with time and experience I will get the results I want, but it worked out and I’ll tell you why. I did not want an end fed for 20m to 10m. I have the yagi for that mounted on a 8ft. roof tower. I found best results for lowest SWR and 50 ohm values using the capacitors I used for 160m thru 30m. Had I wanted it resonant on 20m too 10m I know which and how many capacitors in series that will give me the results I want as I had experimented with in building this balun. When it’s time to play with 160m this balun will play nicely.

 

To truly test this antenna I participated in the CQWW CW contest. I normally run HIGH POWER with my contest station that’ll give K5TR and K3LR a run for their money. I figured I’d run not my IC7600, but my brand new purchased 2 weeks prior IC735, with FL63A 250hz filter with a kick ass 5 watts QRP. Yes, my HIGH POWERED 5 watts. I mod’ed the IC735 for 1-100 watts from its factory 10-100 watts. End results was 151 QSO’s @ 5 watts with a scattered 16hrs of effort out of 48hrs through the weekend where most of my activity was on 80m and 40 meters. Was too busy all weekend with priority’s so played in the event when I could mostly at night in and out of the contest. Only was able too take advantage of the yagi Sunday afternoon around 2:30pm between 20 and 15 meters till band closed then bounced around on 40m. During the CQWW SSB contest I used an FT817 and mostly was able too work during the day mostly on 15m and 20m with a lousy 10 QSO’s on 40m only. This time was different. Here is just an idea of the DX that I was able too work running 5 watts and this end fed installation.

Image.jpeg

 

After the contest I decided to put some fire through the wire by QRP standards running 100 watts through the end fed. Results were as I had anticipated after experiencing how well 5 watts had performed. I will say the patterns seemed too have good lobes about a 340 degree radius. Looking at my logging list and what I’ve seen so far there seems too be a narrow null around 60 degrees north east. Could just be conditions, because I have made EU contacts in that direction. Just not as strong and did not receive as well as in all other directions in comparison.

 

So, in the end for a first time builder of the infamous end fed and 49:1 balun and persistent ham operator that doesn’t listen too those that say “Life’s Too Short For QRP”, or those that would say an end fed oriented in this fashion wouldn’t work well I say this. Guess you were wrong. Don’t be afraid to build and don’t ever doubt Mother Nature propagation extraordinaire.

 

73,

N2RRA / - -.-    .-.   .- - .

N2RRA2020-05-29
Re: Scrap the Traps 80-Meter EFHW Experiment
You guys are very welcome. That’s for the positivity and good luck getting your 75/80m.
Reply to a comment by : KF5KWO on 2020-04-28

This is what I'm trying to do now as well! Thanks for the great article. My intention is to have an EFHW for 75/80. I already have my 40-10m situation taken care of, just want to add 75/80. Thanks again! 73 de Jeff, KF5KWO, San Antonio, TX
KF5KWO2020-04-28
Scrap the Traps 80-Meter EFHW Experiment
This is what I'm trying to do now as well! Thanks for the great article. My intention is to have an EFHW for 75/80. I already have my 40-10m situation taken care of, just want to add 75/80. Thanks again! 73 de Jeff, KF5KWO, San Antonio, TX
VE7KKQ2020-04-20
Scrap the Traps 80-Meter EFHW Experiment
WOW, I'm shocked... where are all the negative Nellies?
Has eHam developed some sort of filter?

Great article and how refreshing to read positive and encouraging comments, well done all.
N2RRA2020-04-19
Scrap the Traps 80-Meter EFHW Experiment
Thanks guys for all your positive comments.
N2RRA2020-04-19
Re: Scrap the Traps 80-Meter EFHW Experiment
Well said
Reply to a comment by : AF5CC on 2020-04-05

"Getting all perfectionistic about antennas just keeps people off the air" Isn't that the truth! The poorest antenna that you can put up is going to make more QSOs than a radio hooked to no antenna! Back in the 90s I worked DXCC using an indoor dipole while in graduate school. Not ideal, but better than QRT. 73 John W5TD
Reply to a comment by : AC7CW on 2020-04-05

Getting all perfectionistic about antennas just keeps people off the air
Reply to a comment by : K0UA on 2020-03-26

Good article, good writeup. Tnx 73 James K0UA
AF5CC2020-04-05
Re: Scrap the Traps 80-Meter EFHW Experiment
"Getting all perfectionistic about antennas just keeps people off the air"

Isn't that the truth! The poorest antenna that you can put up is going to make more QSOs than a radio hooked to no antenna!

Back in the 90s I worked DXCC using an indoor dipole while in graduate school. Not ideal, but better than QRT.

73 John W5TD
Reply to a comment by : AC7CW on 2020-04-05

Getting all perfectionistic about antennas just keeps people off the air
Reply to a comment by : K0UA on 2020-03-26

Good article, good writeup. Tnx 73 James K0UA
AC7CW2020-04-05
Re: Scrap the Traps 80-Meter EFHW Experiment
Getting all perfectionistic about antennas just keeps people off the air
Reply to a comment by : K0UA on 2020-03-26

Good article, good writeup. Tnx 73 James K0UA
N8NK2020-04-04
Scrap the Traps 80-Meter EFHW Experiment
Wonderful article! I love reading stuff like this. I'ts very fun and exciting just seeing what you can do with less. I wound my multi-tap UNUN, threw about 125' of wire over a branch up ~40', and have been working all over the U.S. and lots of DX as well.. using 5 watts. Get this - lately I've worked the Czech Republic on 40, using an EFHW and my multi-tap UNUN - with the wire at 2.5' high on bamboo sticks. lol. It's all on YT if anyone wants to look. 73 OM
W0FAA2020-04-01
Scrap the Traps 80-Meter EFHW Experiment
Path loss due to changes in the ionosphere, i.e. band open or not, makes antenna gain almost irrelevant except for DXing or cracking a pileup. Put another way, if the band is open you can work *someone* with almost any wire in the air. If it's not, your stacked array isn't going to help much. Good job on making the most of what you have!
KE4LJH2020-03-31
Re: Scrap the Traps 80-Meter EFHW Experiment
This is an absolutley fine testament of just get out there and put some wire in the air.

Thanks for the story.

The mark of brilliance, can be measured with,
"THE NUMBER OF WAVELEGTHS PER ACRE!"
Reply to a comment by : K0UA on 2020-03-26

Good article, good writeup. Tnx 73 James K0UA
WA2AM2020-03-31
Scrap the Traps 80-Meter EFHW Experiment
I enjoyed this article thoroughly.

Two years ago I moved into a condo, which obviously imposes very strict antenna regulations. (Basically you can't have one!) I bought a 9:1 UNUN and set up a meandering end-fed that is very well hidden. The highest point is only 30' off the ground. I can work 160 through 10 with it, with not-so-bad results. Adding a 600W Ameritron to the mix helped too - adding a couple of dB can make all the difference sometimes.

Would I rather have full-size dipoles and a yagi 100' up? Sure. But I can't. So I play the cards I'm dealt.

73, Craig
KJ4DGE2020-03-30
Scrap the Traps 80-Meter EFHW Experiment
Excellent article and great words to live by. Building something that works even when others say it will not is a really good feeling. More people should try it.

Thanks again

KJ4DGE
K0UA2020-03-26
Scrap the Traps 80-Meter EFHW Experiment
Good article, good writeup. Tnx 73 James K0UA