I agree that the enamel could just be left on with no ill effects, but:
> 1. The only reason bare wire is specified for AM BC stations is that
> it is cheaper than enamel wire.
The main reason is bare wire is easier to work with, when soldering
hundreds of connections. The cost of the wire is insignificant when
compared to the labor and other expenses in the system.
2. The reason to bury of a radial
> system is so that you can mow the law to keep the XYL happy. An ideal
> system would be on short posts insulated from the earth. (Ground rods
> at the tower take care of lightning ground.)
When a sufficient number of radials are used, it makes absolutely
no difference whether the system has or does not have direct soil
contact for RF. It is only when a sparse, poorly efficient system
with a few radials is used that insulating radials by spacing them
above earth helps.
Insulation on a wire makes no difference at all for a wire in contact
with earth for RF performance, any increase in efficiency comes
from physical separation from earth and that is important only when
the radial system is small. At about 15-20 radials, it makes no
difference at all if the radials are slightly buried or elevated several
feet so far as system efficiency is concerned. With more radials,
all elevating the radials does is hurt the overall system by reducing
effective height.
It is the physical distance the wire is from earth compared to the
wavelength that matters. A spacing of .005 inches from a layer of
insulation is meaningless on any frequency, except near direct-
current.
73, Tom W8JI
W8JI@contesting.com
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