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Re: Topband: Inverted L height vs. length.

To: Yuri Blanarovich <k3bu@optimum.net>
Subject: Re: Topband: Inverted L height vs. length.
From: <ve9aa@nbnet.nb.ca>
Date: Mon, 2 Mar 2015 12:03:39 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Hi & Thanks Yuri.  That's good info to know.  I had wondered about that 
actually...

I may be able to get the hz portion over to a far away tree, just slightly 
lower than the 35' peak of the first tree, instead of sloping it back to earth. 
 I am limited in what I can do, hi !

Appreciate the input.

Mike VE9AA
---- Yuri Blanarovich <k3bu@optimum.net> wrote: 
> Hi Mike,
> 
> from your description, I think you would be best off not to fold back 
> the top wire, but try to "go away" horizontally as much as possible. 
> Folding back in "U" manner makes the current/radiation from the top half 
> cancel portion from the fed portion.
> 
> If you want to enhance vertical polarization and lower angles, try to 
> use "T" loading, that cancels most of the high angle horizontal 
> radiation.
> 
> You might be more efficient to use loading coil (and make it work on 80m 
> as a trap) at the top and shorten the loading end of wire.
> 
> I have great results with my Inverted Vee in a Tree, top at abt 40 ft, 
> with ends drooping down and going horizontal at about 10 ft. I have high 
> water table. I am surprised how well it works, suspect that ends are 
> acting as "radials" to the sloppy top fed vertical, no stinkin baluns, 
> perfect 1:1 50 ohm match.
>  
> 73 Yuri, VE3BMV, K3BU.us
>  
>  
>  
>  On Sat, Feb 28, 2015 at 01:39 PM, Mike & Coreen Smith VE9AA wrote:
>  
>  > de VE9AA
> >
> >
> > I know inverted L's have been hashed out quite a few times on this 
> > list, and
> > I have gleaned some knowledge.  At my previous QTH I had a 5/16th WL 
> > one
> > which seemed to work tons better than my current one, even though I 
> > was not
> > up over 40' high.
> >
> >
> > As it happens, on my current property I don't have any towers, nor 
> > tall
> > trees so I have a general question.
> >
> >
> > As far as a 127' inverted L goes, do I have anything to gain by 
> > sloping the
> > "vertical" portion of the wire slightly up to a short treetop, vs. 
> > going
> > nearly vertical, then the rest horizontal?
> >
> >
> > Example:
> >
> > I have a 35-40' tree nearish to where my coax exits the ground from an
> > underground run.  I slope it "up" so essentially I have likely close 
> > to 50'
> > of "vertical" then the remainder meanders through some shorter 
> > treetops and
> > comes back to ground rather quickly (unfortunately it's more an 
> > inverted U
> > than L).  I have a few thousand feet of radials mostly in the southern
> > portion of the field under  the "horizontal section". A 800pf Cap is 
> > at the
> > base and my SWR is around 50-60Kcs at the 2.1:1 pts.  I seem to do 
> > quite
> > well into w1,2,3,4,8 and at times western EU/Carib.  Anything outside 
> > that
> > sucks.  That tells me I probably have gobs of high angle radiation.
> >
> >
> > Have I anything to gain by putting the coax directly under the tree, 
> > going
> > perfectly vertical for 37-ish feet, then, sadly, pretty much "down to 
> > the
> > ground" for the "horizontal" section same as the original?
> >
> >
> > (hope this ascii art works)
> >
> >
> > Ie:  This is what I am doing now (wire is around 65*-70* vertical or 
> > so_)
> >
> >    ___
> >
> >  /        \
> >
> > /            \
> >
> > /               \
> >
> >
> >
> > but I wonder of this is any better
> >
> >
> > __ _
> > |        \
> >
> > |          \
> >
> > |            \
> >
> >
> >
> >
> > Lastly, I could go farther away from the tree and try to get 80-90' of
> > sloping wire (likely closer to 45*) and then have the remainder droop 
> > itself
> > back to Earth.
> >
> >
> >    _  _ _ _
> >            /             \
> >
> >         /                 \
> >     /                      \
> >
> > /
> >
> >
> > Anyone have a skyhook for sale?
> >
> >
> >
> > Thanks for any insight.
> >
> >
> > Mike VE9AA FN66na @ 660' ASL.rocky ridgetop.
> >
> >
> > Mike, Coreen & Corey
> >
> > Keswick Ridge, NB
> >
> >
> > _________________
> > Topband Reflector Archives - http://www.contesting.com/_topband
> >

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