I use 502 insulators which are easy to find used and wind up being as cheap
as thimbles. Mechanically they produce no chafing as thimbles might from
rubbing against each other.
This also works quite well with Polyrod.
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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