[TowerTalk] re Antenna in wet soil

[Rob Atkinson, K5UJ]

Wet ground improves ground conductivity but not so much that you can get by 
with a limited radial system.    so you still need to put down a lot of 
radials if you want a good antenna, but you don't necessarily need to bury 
them unless you have some other reason for doing that apart from antenna 
performance.  the antenna will work the same whether they are laid on the 
surface of the ground or submerged a few inches and if the ground is wet all 
the time they will probably disappear into it soon anyway if laid on top 
where there is grass.

If your vertical base is going to be regularly sprayed, I'd get your 
feedline connections, i.e. any point out there where you can have moisture 
migrate into the feed, such as a barrel connector splice or the feedpoint, 
and waterproof them.   Instead of using coax seal or silicone which is 
messy, i simply place such vulnerable points as mentioned inside plastic 
sleeves.  you can use the type newspapers are delivered in and arrange them 
loosely so the water rolls off and doesn't flow into them but there is still 
air circulation in and out of them.   This plastic usually fails because of 
uv damage after around 12 months, but because your feedline and feedpoint 
are at ground level these are easy to change.   this has been working for me 
and i have never had a problem with any water getting into any feedline.  Of 
course for hard to get places such as up on a tower you would want some 
other method.   i'd take a look at the exposed antenna hardware from time to 
time during the first 12 months to see if the composition of the spray is 
more corrosive than regular rain water.

73,
rob / k5uj

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