Topband
[Top] [All Lists]

Re: Topband: 8 element antenna - Amplifier placement

To: topband@contesting.com
Subject: Re: Topband: 8 element antenna - Amplifier placement
From: Bob K6UJ <k6uj@pacbell.net>
Date: Mon, 19 Sep 2016 12:03:12 -0700
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Gary,

The Hi-Z's are said to be great receive ants.  Let us know how
yours performs.
I cant offer anything on the preamp enclosure but I can
offer some info on the paint.
I used Krylons Camo spray paint on two verticals and it worked
very well.  No RF issues.

Here is the stuff:
https://www.amazon.com/Krylon-K04293000-Camouflage-Technology-11-Ounce/dp/B00176UX26/ref=sr_1_1?ie=UTF8&qid=1474310890&sr=8-1&keywords=krylon+camo+spray+paint

Bob
K6UJ



On 9/19/16 10:41 AM, Gary Smith wrote:
I'm so close to being done with putting
this together. I have all 8 antennas made
@ 23' each the tip section is .5" and the
base is .850" I'm using a 3/4" fiberglass
rod as an insulator

doctorgary.net/Hi-Z-8-Pro-1.jpg
doctorgary.net/Hi-Z-8-Pro-2.jpg

I am having a conundrum with the placement
of the enclosure for the preamp mounted at
each antenna and need some advice. The
problem is I am at sea level and the
antennas will be mounted in a location
that will possibly get a storm surge
during a Hurricane, it ruined my remote
coax switch during Sandy from this very
reason. The preamp does have a silicone
gasket but if the amp gets submerged in
salt water, I'm sure it will get past the
terminals and ruin the amp. I have no
alternate choice, this is the location
where I have to put the array.

Seeing the photo of the end cap on the PVC
tubing with the zip tie holding the amp in
place (to protect from rain & Snow), gave
me an idea for the solution; At the top of
the PVC tube, make two opposing holes, run
a loose loop of thin wire through and
twist together. Run the coax up & over the
wire to hold the amp elevated inside the
tube, all the way to the top. Use a rubber
cap with radiator clamp to secure the top
and make it truly airtight. Now if the
tide water from a storm surge encroaches,
there will be a pocket of air inside and
will be unable to push high enough to
reach the amplifier. I tried this with a
Mason jar and the water did not get very
high in the upside down jar.

doctorgary.net/Hi-Z-8-Pro-3.jpg

So here's the dilemma: As a further hedge
against water damage assuming there are
strong winds making waves (they would not
be breakers, just waves in the marsh) at
this time, I'd like to raise the placement
of the amplifier so it would be another
foot higher than standard placement which
is on the base below the insulator. This
would require me to clamp the PVC on the
antenna instead of the base. Can anyone
see how this might be a problem with
operation?

Also, I'd like to spray camo paint on the
elements so they don't stand out. When the
leaves come down, I'd prefer the neighbors
not see the elements, they're nosy enough
as it is. I think I remember reading a
layer of paint on the element shouldn't
cause a problem, is this correct?

Thanks & 73,

Gary
KA1J



_________________
Topband Reflector Archives - http://www.contesting.com/_topband


_________________
Topband Reflector Archives - http://www.contesting.com/_topband

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