Topband: 8 element antenna - Amplifier placement

Gary Smith Gary at
Mon Sep 19 13:41:53 EDT 2016

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

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. 

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 

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,


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