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[KE8UWU]

Looking at purchasing a 133 ft all-band 80-10M EFHW antenna. I've seen other posts and articles on this topic but hoping I can get a "plain english" answer with me being a new General.

Like most, I like in a neighborhood (no HOA), but do have limited space. I have a tree that's probably 30' tall that I have access to in my yard but I don't have a lot of length.

If I made an inverted "L", and I put bends in the L, will that cause an issue or limit the antenna in any way?

Example: Transformer and feed-point will start at 5' off the ground, wire goes up to 15' off the ground then horizontal out 41', takes a turn, then out another 41', and then makes one final turn to finish out the final 41'. Basically the entire 123' would be horizontally polarized and would almost make a square (3 sides out of 4 sides). Will that be ok? Ideally I could toss this 30' in a tree and slope it all the way down but I have a square shaped lot that I can use as best I can. I do have a 6' privacy fence that closes in my yard so I'm looking to use that fence line as a way to extend the wire.

Forgive me if my terminology isn't perfect. I'm learning and greatly appreciate any insight. Really enjoying my radio and my current EFHW which is 10-40 is working great. Inverted V configuration and is getting out very well. Now I'm just wanted to expand into 80M and also pick up 4 bands. My current antenna is resonant on 4 bands currently. Thank you again for any insight and help.

Shane (KE8UWU)
Swr0018@gmail.com

[WB6BYU]

There is nothing inherently wrong with that configuration -
it should support reasonable local coverage on 80m and
40m, and longer distances on the higher bands.

One issue, however, is that a wire with bends in it requires
more wire for the same resonant frequency than one
that is straight.  And the effect varies with where the
bends are positioned relative to the current distribution
on the wire, so won’t be the same on each band.

The end result is that you might need to lengthen the
wire slightly, and the SWR dips might not line up
across different bands as well as they would otherwise.

But it should still work - just might need a bit of
help from a tuner on some bands.


Not a bad place to start, at any rate...

[W1VT]

My approach is to build antennas with separate radiating elements and feedlines for 80 and 160 meters.
The lower bands are hard enough I think it is worthwhile to optimize radiators for both bands top work DX.  I work the radiators against four short elevated radials.
I have a top loaded vertical for 80 that works really well for DX.  Last night I worked some Europeans and nobody else seemed to be getting across the pond at that time.
Mine is just 40 ft tall.  I don't care about working locals so I don't need to work short skip on 80.
But in the past week I've worked 5R8, K8H (American Samoa), VK3, JH7, JH1, HB9, ZL1, G3, and VK6 on 80.  VK6 is about as far as I can go.  11640km
My backyard is 70x100 ft and I can walk to  McDonalds in ten minutes.  On 160 I have  bent Inverted-L that goes up 36 ft.  DX is a lot harder on 160 but I do have 150 confirmed.
Zak W1VT

[K9RJ]

Zak, You are getting impressive results with your 80 meter vertical. Do you have loading coils in your short elevated radials to get them to be resonant? Having lived and operated in VK6 for 7 years (2001-2008), I am impressed.
Harris K9RJ (ex VK6AV, VK4CWT)

[K9ARM]

My situation is somewhat similar - EFHW 130ft +/-, feedpoint at 7ft on shed, up to 30ft on tree, 80ft to tree, the 90 deg 40 ft to another tree. It's tuned for 3600, the rest of the bands fall into place, but need tuner from 3800 up on 75 mtrs. Works great, pretty stealthy. Yours may be more of a cloud burner being mounted lower, especially on the lower bands. Try it, it will probably be fine. Using XMFR from My Antennas, I supplied wire.

BTW, I travel for work and make it into MI and Lansing fairly often. I'm active on Midcars 7258 and tune around a lot in the mobile. Have V/U also, but mostly on HF.

Andy K9ARM

[W1VT]

Hi Harris,

Thanks for the compliment.  No loading coils.  I use symmetry to get the current to divide equally between the radials.
They are five feet off the ground.  I'm short and the only one who uses my back yard so that works for me.

Instead, I adjust the top loading wires for resonance.  Now in the CW portion of the band, but I have moved it temporarily to the Phone portion for a SSB contest.
I also have a 50:25 ohm transformer at the feedpoint so I can run the antenna without a tuner.

When I first put it up ten years ago I had a blast getting my 80M DXCC in three months running 100 watts.  I was getting new ones confirmed in the mail every other day!
That was before digital became popular.  I also worked a lot of old timers who never did LoTW so I sent out paper cards.

Zak  W1VT

[W1JPP]

Hi Shane - over the years I've tried many antennas...beams, dipoles, loops (delta and horizontal), off center fed, and end feds...

Right now my only two antennas are my 80m end fed (fed with 49:1 transformer, and its cut for 80m with a capacitor in the center, so its resonant on 75 phone and the higher up bands). I also have a 160m (length) dipole fed with open wire...

I really like the simplicity of the end fed..I tend to try an antenna and if I dont see great improvement with a/b tests over what I have over a several week period I'll take it down...over time, the end fed has stayed and is used most of the time...

I would not worry about the configuration...get the 80m band wire up however you can...mine is fed at 15' and goes at a 70 degree angle up about 40' and then horizontal the rest of the way...

Also, think about what you are interested in...in my case I wanted to be able to carry long distances on 20m, 17m etc all the way to more local comms on 80 and 160...I was on 80 earlier and having qso's with people as close as 100 miles from me (in rhode island) down to people in florida who were 20 over 9...but I'm not real interested in 80 and 160 dx....I like being able to cover the various distances with different antennas and bands...

Once while living in maine I had a 450' horizontal loop at 70' - I loved it...Used to have qso's with the same guy in slovenia each day, so I knew my typical signal (tx and rx)....one day after a qso with him, same signal reports as always...strong...I came out of my shack, only to see my loop had fallen during the night and was laying on the ground, around my house...

Now, I would never suggest a loop on the ground would work well....but I also realized that if conditions are decent, you cant get too caught up in modeling...things that would never work on paper may work fine, relatively speaking...

yesterday, I wanted to build another portable setup...so what did I do, I built a 49:1 transformer...meaning of the options available, I chose to do another end fed for my portable setup...just easy to deploy with relatively good performance...

You'll like 80m...I find most nights now, I spend my time on 80m, with some 160m mixed in...

[N4UFO]

Have not read entire thread but wanted to address one question...

Transformer and feed-point will start at 5' off the ground, wire goes up to 15' off the ground

Go with 1.5 feet above ground. Others have done it, I did it, seems to work out well. Mine is mounted on a metal stake and the transformer is grounded to it to help with static discharge. (make little to no difference with SWR and tuning) Then I put a common mode choke (coax wound through toroids) at a non-resonant distance from feedpoint to choke. Mine is made for 160m through 40m and have worked the world with it. See pics on my QRZ page (scroll down):   https://www.qrz.com/db/n4ufo

As for the bending, direction, etc... it may change the tuning a bit and cause you to need a different length. Mine takes a sharp turn back towards another tree and as a result, my wire is resonant (where I want it) at 269' instead of the expected 260'. As always, your mileage may vary.

73 & GL, Kevin N4UFO

[KE8UWU]

Thank you everyone for the feedback and notes. I'm reading through each one of them and figuring out how I can make it work. This helps a lot!

[RFRY]

... If I made an inverted "L", and I put bends in the L, will that cause an issue or limit the antenna in any way?

Example: Transformer and feed-point will start at 5' off the ground, (etc) ... Thank you again for any insight and help.

Below is a NEC4.2 study of what the performance of the antenna system will be for the conditions shown there — which are based on your OP.

The load match for a 50 Ω coax feedline connected to the EFHW input transformer will depend on how closely the transformer can match the R and j(X) impedances to the coax, across the various bands in the top graph at the right-hand side of the graphic.

EFHW antenna configurations may have higher peak gain(s), but more lobes in their radiation patterns on the higher bands than on the lower bands.

[KE6VG]

Those 12m Spiderbeam poles make a great center support for EFHW antennas. And you can put them up in trees, against the house etc.