One pointers are great for experimentation

Flint peak (w6/ct-225) is an easy 1 pointer here in LA I’ve avoided for years, but I hit it this morning with some experimental gear in tow.


Decided to try out my 20m 1/4 λ vert again (just a wire on a pole folks). New to the field this time is my homebrew parachute deployed radial field. There are 24x1/8 λ (for 14 mhz) radials. Sets up in a hurry, no tangled radials, no tuning required to drive with the MTR3b. I wouldn’t want to use the chute in wind, but the light breeze today (5-10 kts) was no match for the hunks of quartz I layed on it. The radials also worked pretty well against a 1/4 λ 40m inverted L. Great results! 21 qsos all together, the second qso being with F4WBN. The RBN showed decent snrs across the continent on 20 and 40.

Also new to the field today was my 3d printed homebrew key (Plas-Ti-Key). It performed pretty great (op skill could have been better.) I managed to use both the iambic and straight key functionality.

STL file is over here:
https://www.thingiverse.com/thing:4579188

73 KB9ENS

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Good work testing out the kit, it’s a great pass time for me. I do many tests in my back yard with kit by chasing SOTA or VKFF [parks] ops out in the field. I figure if you can make Yard to Summit or Park QSO’s with your SOTA kit it should work ok from a Summit. Like your key too it looks like a couple options there.
Regards
Ian vk5cz …

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Do you think that chain-link fence behind you affected performance? I assume that was on the easterly side of your antenna.
Regards,
Mike, WB2FUV

It might’ve had some effect I have my doubts as to whether any portion of it was resonant with HF. Fence was to my West side. There is also an antenna farm pumping out RF on all kinds of frequencies I am unaware of right behind the fence. shrugs

My model assumed an adiabatic isentropic frictionless superconducting fence. All models are wrong, some are useful. /end joke

Hooray for field testing.

Sorry I missed you, Tom. I was just getting out of bed while you were wrapping up.
Flint Peak is only 3 miles away; I could have worked you without an antenna, hi.
Kudos for the radial deployment method! The paddle looks good, too.
Flint has a marvelous drop off from west to southeast which provides signal enhancement.
I’ve operated some contests from up there, hence the need for a table.

73,
David N6AN

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That is a fine business music stand setup there David!

Well, you had a good signal on 40 this morning !
Wonder if that antenna setup works on 60M ? That band works
real good for “local” QSOs during the day. (Local being CA, NV, AZ, OR, etc.).
73
John, K6YK

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John,

An inverted L for 60 would probably work fine over the radials. Just a matter of cutting wire to the right length for the “L”. The value, to me, of the “vert over lots of radials” design is that it should pull more energy down to lower angles (hello dx). If the objective is “local” … having low angle radiation isn’t really what you’re after. Could probably just do the “L” with a single radial and get a more spherical pattern. Probably worth modeling in MMANA or some such to see what the predicted patterns are given the vert/horiz pieces of what you might be able to throw up.

The way I support the vertical portion of my “L” is limited by the height of my pole and so would provide me with quite a substantial horizontal element on 60. It all depends on the orientation of the wire where the RF currents are “high”. There’s nothing saying that you couldn’t throw it over a higher limb or fly it from a kite or something if you want to get that 60m DX though, but then of course a 5/8 wave would be best to really crush the pattern.

I really like having 60 when I have my KX2 and random wire combo for the same “local” work purpose, alas my MTR3b is only set up for 20/30/40. In driveway testing I did try to just add a tapped coil and some permiability tuning to the base of the vert (pictured below), and it worked fine with one radial, I could shift resonance all over the place, but with the whole field of 24 radials I didn’t have much success. I suspect if I had some ground tuning in circuit I could make it work, but man… the whole point was to be simple and not require tuning so I suspended that line of experimentation.

73
Tom, KB9ENS

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