Thank you!
Ed
> On Sep 23, 2018, at 6:22 AM, <chris@profile-technology.com>
> <chris@profile-technology.com> wrote:
>
> 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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>>
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