Topband: Base Insulators for Verticals
Jon Zaimes AA1K
jz73 at verizon.net
Sun Sep 10 08:40:37 EDT 2006
> Using three separate insulators, one in each leg of a
>> guyed tower, is about
>> the WORST possible approach.
I have several towers using 6-8 inch diameter power line ceramic insulators at the base. Any one of these would support the tower, but using three meant I could use one under each leg rather than having to reinforce the standard steel plate on a BPC-25G or BPC-55G.
The bottom of the insulators is attached to a second steel plate that sits on a pier pin, so that gives some "flex" to the system and allows for rotation of the tower in high winds. My 160-meter tower has been in service more than 8 years, through some 60-80 mph windstorms. No sign of cracking or deteroriation of the insulators.
To test the original insulators, I took a spare, cracked one and put it between a couple of boards, then drove over it with my Jeep a few times.
Some pix of these at www.aa1k.us under "towers"
YMMV but this works for me.
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