Homebrew 3 Element Yagi for 6m

[Crawdad]

One of my favorite aspects of this hobby is building antennas. Up to now it's only been wire antennas such as Inverted V's for HF and a wire 2 element Moxon for 6m. Since I have a guyed fiberglass push-up mast that will do 30ft, I decided I wanted to try homebrewing a lightweight, 3 element Yagi for 6m. After a short Google search I found a design I liked: https://www.n5dux.com/ham/files/pdf/Build the Featherweight 6m Yagi.pdf

The K1BQT design uses 5/16" OD 6061 aluminum tubing for the elements, but I couldn't find a supplier near me that stocked it or was willing to order it in. After a bit more searching I found a place in town that stocked 1/4" OD x 144" 6061 solid rod at a reasonable price and the length I needed, without any shipping costs. The difference in weight was negligible. Adding in a 1"x1"x10' piece of square tube for the boom brought the aluminum cost to under $50.

I did a lot of EZNEC modeling (and learning) of the antenna using the K1BQT dimensions for element length and spacing, then adjusted the Director spacing from the reflector from 72" to 83-1/4"to increase the gain while staying within the boom length and weight limits I wanted.

The parasitic elements run thru the boom. The Driven element mounts to a piece of WalMart plastic cutting board.



The Hairpin/Beta match was made with the drops from cutting the elements. I chose to make it adjustable for easy tuning. A couple strips of aluminum flashing connected the mobile antenna SO239 to the Driven element.


Since the antenna is on a push-up mast I was able to tune it at the 30ft final position that it was modeled at.
The initial sweep wasn't bad:


After a few adjustments of the Hairpin:


I'm happy with those numbers. Seems to work well, a couple of nice signal reports from stations 80 and 100 mi out, was told signal stronger than before with the Moxon I used. 6 meters being 6 meters the band hasn't opened up for any real DXing yet, but I'm patient. Would love to reach Europe or Africa with this antenna and 100w.


Thanks to K1BQT for publishing his design, I borrowed heavily from it and it seems like a good one for a super light 3el Yagi, weighing in at around 5lbs. Could easily be 4 elements with a stouter mast or tower. It was an easy and enjoyable build and could be designed and built for a featherweight 2 meter Yagi for not a lot of $. Time will tell on its DX performance, need Mother Nature to cooperate.

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[w9cll]

Nice! Building antennas is the best part of the hobby for me.

 

[Crawdad]

Nice! Building antennas is the best part of the hobby for me.

Thanks. That makes two of us. Thoroughly enjoyed building this one.

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[fourstringburn]

Nicely done!

Looks like it's about 36ft up in the air. Should work very well when 6m is open. I see your analyzer shows a full Mhz of bandwidth under 2.1 and the phone portion is the sweet spot.

I recently added a 6m dipole element that sits on top of my Mosley 5 band beam. I just copied the MFJ design used to add 6m to their rotatable dipole. Works OK on local ground wave, haven't got any DX yet.

Are you able to strong arm rotate it or just have it in a ideal fixed position?

 

[Crawdad]

Thank you sir,

like it's about 36ft up in the air

It's almost exactly 30ft from the base of the mast but the ground slopes downward on the east side and rises slightly on the west side.

I see your analyzer shows a full Mhz of bandwidth under 2.1 and the phone portion is the sweet spot.

I purposely designed and tuned it for the SSB portion of the band, basically from 50.100 to 50.200, I don't do any other modes on 6m.

I recently added a 6m dipole element that sits on top of my Mosley 5 band beam. I just copied the MFJ design used to add 6m to their rotatable dipole. Works OK on local ground wave, haven't got any DX yet.

That's a good idea making it rotatable, I started out on 6m with a fixed 1/2 wave flattop, it didn't work very well. Quickly went to an armstrong Moxon with much better results.

Are you able to strong arm rotate it or just have it in a ideal fixed position?

It's easily rotatable via the armstrong rotator
A small tv rotator may/could be added at some point.

Maybe we can meet on the air someday. 6m SSB needs traffic.........

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