On 6/26/2012 5:30 PM, Rick Kiessig wrote:
> Is it a good idea to create a coil of coax in or near the base of the
> tower,run through ferrite toroids?
At a minimum there should be multi-turn ferrite chokes right at the
antenna feedpoint, using my Choke Cookbook as a guide for winding them.
As Roger has suggested, an additional choke further down the feedline
can break up the common mode circuit, acting like an "egg insulator"
does on a guy wire. I would start with the first one at the feedpoint
and add others if needed.
Roger has also given you good advice on bonding the shield at top and
bottom, and on the coax. It's worth "doing the sums" to compute feedline
loss with various options, but also to consider how well various cable
types hold up over time.
73, Jim K9YC
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