Mike,
The procedure described by Wes below is exactly the approach I would
take. If you do this, I'm betting that you are left with #1 below,
since you said you previously had your antennas over "soggy ground."
Rocky and soggy are significantly different.
Good luck with your gremlin chasing.
73,
Ken - K4XL
Wes Attaway (N5WA) wrote:
> Mike:
>
> 1. Maybe the type of rocky ground is the reason.
> 2. Take down all the other wires and check the L (or T) by itself, still
> using switchbox.
> 3. Take out the switchbox and just feed the antenna directly (still by
> itself, no other wires)
> 4. If things are still bad then the problem probably has something to do
> with your location.
>
>
> ------------------ Wes Attaway (N5WA) ------------------
> 1138 Waters Edge Circle - Shreveport, LA 71106
> 318-797-4972 (office) - 318-393-3289 (cell)
> Computer Consulting and Forensics
> -------------- EnCase Certified Examiner ---------------
>
>
> -----Original Message-----
> From: topband-bounces@contesting.com [mailto:topband-bounces@contesting.com]
> On Behalf Of Mike & Coreen Smith
> Sent: Saturday, November 07, 2009 6:44 AM
> To: topband@contesting.com
> Subject: Topband: Low Alpha Delta DX-A twin sloper BEST antenna here -
> howcan that be?
>
> Sorry for the long and rambling post. . . .
>
> OK gang, I know antennas "fairly" well, but this has me stumped...really
> REALLY stumped. I've beat myself up over this for 2 yrs. straight. I just
> can't get it. I am (almost) ready to rip everything down and start from
> scratch)
>
> I posed a ~similar~ question last year and have tried some different things,
>
> but I'm losing my patience with the wire here (hi)
>
> BACKGROUND:
> At my old QTH, I ran an inverted L...5/16thWL and fed with a 800pF cap in
> series. A dozen to two dozen 1/4wl radials(depending on how many got broken
>
> in the summer)over soggy ground. It meandered up 50-ish or so feet with the
>
> remaining 117' up/down/over/under trees --even the tip sloped back towards
> the ground 20' or more.....and it ROCKED....I mean, I wasn't any VE1ZZ or
> anything but I felt I was upper middle crust of the W1/VE1 pileup. I also
> had the exact same tower and exact same Alpha Delta DX-A twin sloper up (for
>
> reference) and it s*cked...really bad. Easily several S units below
> anything else on 40-80-160m
>
> NOWADAYS:
> Fast forward to new QTH...same 48' DElhi self supporting tower set in
> concrete....same 2 long 6m yagis on tower (48/64')....same lil' sloper
> mounted @ 24' off side of tower....
> I have tried 2 iterations of a plain inverted L.....currently it's a "T"
> antenna. Sloping 55' or so up and 2 T's @ 55' or so each sloping @ aprox 45º
>
> to the ground....loads nicely with a few uH @ the base. Seems quieter than
> the A-D twin.
> I have tried shunt -and- series feeding my 48' tower (no problem to do).
> They have all loaded well and I got a good SWR match with a usually narrow
> window 50Kcs maybe of 2.1:1 SWR of which to operate in. I have 25 or so
> 1/8wl to 1/4wl radials - 1" below the grass. Ground is rocky shale? sort of
>
> stuff. My QTH is on a nice high ridge and I do quite well on VHF and other
> HF bands.
>
> My signal is pitiful on **all** the 160m antennas I've tried....with the
> exception of the 1/4WL Dx-A twin sloper @ 24' !!! (it's best but it barely
> works)
>
> The little/low twin sloper off the side of the towe is ALWAYS the loudest on
>
> the band....by usually 6dB or more........I know this can't be right.
>
> How can this be? I am using a 4-1 antenna switchbox (Ameritron I think) @
> the base of the tower which the antennas all share. Many years back I
> modified it so all antennas "floated" (instead of being grounded) when not
> selected as I was using this as a K8UR sloper system switchbox at one time.
> I am pretty sure (but not 100%) that I even ran a separate chunk of coax
> right out to an inverted L last fall in desperation. I do lots of antenna
> experimenting, so it's sometimes hard to remember the 45th iteration of a
> trial I had a couple years ago, hi.
>
> I *DO* notice significant SWR curve changes on the lil' wee sloper if I make
>
> any mods to any of the other "REAL" 160m antennas.
>
> I either have interactions in the switchbox, or proximity between antennas
> or something that I am totally missing. All 160m antennas are quite close
> (less than 20-30' away).
>
> Logic tells me there is no way in heck the very low Alpha-Delta DX-A twin
> sloper can __always__ be the best antenna to transmit and receive on. YET
> is is !!? From what I see on the cluster, web and hear on the air, I can
> hear quite well, but DX stations normally have to be 559-579 before I even
> get a QRZ.....I am currently running ~750W.........
>
> I'm cracking up.....too much listening to QRN.......sorry for the long post.
>
> Thanks for any insight. I am ready to put a Webster Bandspanner on my
> mobile and go sit out in the yard and DX.
> <hi>
>
> VE9AA Mike
>
> Mike, Coreen & Corey Smith
> 699 Rte 616 Keswick Ridge
> NB
> Canada
> E6L 1T1
> _______________________________________________
> 160 meters is a serious band, it should be treated with respect. - TF4M
>
> _______________________________________________
> 160 meters is a serious band, it should be treated with respect. - TF4M
> ------------------------------------------------------------------------
>
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>
--
Ken K4XL
k4xl@arrl.net
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160 meters is a serious band, it should be treated with respect. - TF4M
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