Hello Gary,
Spray painting the elements is no problem. As far as mounting the amps to
the elements I would not recommend that. It likely could compromise
performance. It would be much better if you could take a steel post like a
piece of rebar and provide a second place for the amps to mount with just the
wires reaching the element and ground. If you have to lengthen the leads to the
amp do not lengthen the ground lead any more than absolutely necessary.
Lengthening the element wires will have to be done exactly the same length and
dressed as closely the same way as possible on each element/amp.
Lee K7TJR
Subject: Topband: 8 element antenna - Amplifier placement
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
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