My first response to this topic was direct to Joe, W2BHK,
and not on reflector.
I didn't find that my t8 @ 60' was particularly noisy...
although the SteppIR seemed a bit quieter, when it went up.
Some peculiarities of my LPDA installation:
* An R7000 vertical was above it.
* Based on w8ji observations, I added a clip-on choke to
the coax, where it came off the boom. (12x 1", type 73 ferrites.)
* I grounded the coax shield to the tower, using bulkhead fittings to
break out the shield, at both top and bottom of tower.
* Feedline was taped inside the tower leg.
* Rohn 45G was grounded with rods & short radials.
* The vertical's feedline was similarly treated, and taped inside
a different tower leg.
The reason for this exercise was to decouple the vertical's feeder
from the lpda's, not noise reduction. But reduced precip static may
have been an unintended consequence.
If Corona is the mechanism, then the topside vertical would have
provided a better discharge path. I never observed noise differences
between the vert & LP...which doesn't mean they weren't there. May be
I simply didn't look at the right time.
In general, the system didn't strike me as particularly noisy. When it
WAS, was during Vermont snowstorms, and everything was noisy, including
insulated dipoles and vertical GP's hung from trees.
n2ea
jimjarvis@ieee.org
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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