Topband
[Top] [All Lists]

Re: Topband: Low Alpha Delta DX-A twin sloper BEST antenna here - how ca

To: "Guy Olinger K2AV" <olinger@bellsouth.net>
Subject: Re: Topband: Low Alpha Delta DX-A twin sloper BEST antenna here - how can that be?
From: "Mike & Coreen Smith" <ve9aa@nbnet.nb.ca>
Reply-to: Mike & Coreen Smith <ve9aa@nbnet.nb.ca>
Date: Sat, 7 Nov 2009 11:15:37 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Guy & All,   Thanks for the comments and questions related so far.

Both installations are pretty much identical. (except for ** See below)
Tower and inverted L are always close. (10-20') perhaps
A-D twin sloper attaches to tower @ the 24' mark. (pretty gosh darn low for 
160m for sure)

**But here:

  a..  I am using a common switchbox now (with non selected antennas left 
floating).
 and
  a..  the ground is very poor.  Shale I think it's called. Rocky layers and 
some big rocks/small boulders like slate, but a much lighter tan colour. 
Can be broken up with a steel rod if you pound on it.  A very thin layer of 
rich but rocky soil on top.  It was pasture land for perhaps up to 100 
years.  I am at one of the highest points in a 20-30 mile radius....IE: I am 
running my internet on a 2.5GHz system to a tower 21kms/14 miles away !! Old 
QTH was wet, cedar swampy, near a lake/river also.

The only reason I have not removed the A-D twin sloper is because I would 
have nothing to compare my Inverted L (or T in its current form) to !

Maybe I should just remove it and judge over time how well I am doing? (hard 
to beat the ol' A/B comparison though, hi)

ve9aa


Mike, Coreen & Corey Smith
699 Rte 616 Keswick Ridge
NB
Canada
E6L 1T1
  ----- Original Message ----- 
  From: Guy Olinger K2AV
  To: Mike & Coreen Smith
  Cc: topband@contesting.com
  Sent: Saturday, November 07, 2009 10:45 AM
  Subject: Re: Topband: Low Alpha Delta DX-A twin sloper BEST antenna here - 
how can that be?


  Can you supply some details about how you had the inv L suspended 
originally (supended from tower? distance from tower? etc) and same info for 
the new setup?

  73, Guy.


  On Sat, Nov 7, 2009 at 7:44 AM, Mike & Coreen Smith <ve9aa@nbnet.nb.ca> 
wrote:

    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





------------------------------------------------------------------------------



  No virus found in this incoming message.
  Checked by AVG - www.avg.com
  Version: 8.5.425 / Virus Database: 270.14.52/2485 - Release Date: 11/06/09 
19:39:00
_______________________________________________
160 meters is a serious band, it should be treated with respect. - TF4M

<Prev in Thread] Current Thread [Next in Thread>