Hi Guy and Ed
STEALTH 80 METER ANTENNA
Just read your emails ref antenna wires in trees which I found interesting.
For some 14 years I was able to use an overhanging branch in a Scots pine in
the land behind my garden (yard) to support both 160 meter and 80 meter
systems at some 80 feet. When the land was sold recently the situation
changed and I m now using a 50 foot Holly tree to provide for an 80 meter
vertical.
My method has been to use a 40 foot fibre glass pole (mine is from from
'Spiderbeams' but any would work), I run a 66 foot wire into the pole with
the remainder trailing from the larger end. I use a pulley system
comprising thin marine line, pulleys and a small winch (driven by golf cart
battery) relay controlled from the shack to raise the pole THROUGH the Holly
tree so as to be a full quarter wave 80 meter vertical. The antenna is only
raised to full height when required i.e. mainly from just before sunset to
just after so covering grey line and night periods. I also use a FCP system
as I have found this much more effective and easy to resonate than a
mediocre radial system.
Even though the main radiating portion is within the tree this set up out
performs, on DX, a low level sloped loop and works reasonably without being
raised to full height.
I have found over some 45 years of holding a transmitting license that all
you can do is your best and as Guy says 'muse and invent'.
Hope this note provides some ideas.
Best regards to you both and the Reflector group.
Chris G4BGM
-----Original Message-----
From: Guy Olinger K2AV
Sent: Sunday, September 23, 2018 11:06 AM
To: navydude1962@yahoo.com
Cc: TopBand List
Subject: Re: Topband: Inv L in Tree
Hi, Ed,
Taking the vertical wire up next to the tree trunk will be fairly lossy.
That usually also means that some part of the horizontal wire is going
through the tree canopy, which will be further lossy. See k2av.com . Click
on the green index button "Place an Inverted L". Also read "Design an
Inverted L", "Place an FCP" and "The Loss List". Note the issue with not
having trees (or parts of them) "inside the bend" of the L. Read them all
with an eye to understanding the loss issues.
There certainly are situations where a variety of local constraints will
make the most efficient method otherwise inadvisable, e.g. wire in
neighbor's tree not being seen. :>)) Oh, what an enormous advantage are
great relations with the neighbors!
But, while you are the only one who really knows what you can and can't get
away with, if you know what causes RF loss in an antenna, then you are also
the only one who can muse on the problem for a while and invent a variation
in the arrangement that stays within your local restraints **and** avoids
most or all of the loss.
Let me know off-reflector if you want to discuss this over the phone. That
is sometimes a lot more direct and far less time consuming than email.
In any event, good luck with it & 73,
Guy K2AV
On Sun, Sep 23, 2018 at 1:39 AM Edward via Topband <topband@contesting.com>
wrote:
Has anybody snaked a wire up a tall tree trunk to make an Inv L?
Any interaction? Success?? Has to be stealthy because the tree os my
neighbor's :-)
Thanks,
Ed NI6S
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