[Antennas] spencer dipole from Mccoy's book

[Pastor-KC1DI]

snip
> OKnow please tell me the difference between window line and open ladder
> line.   I have wondered about what the rain would do to the line.  So it
> makes the line "lossyer"?
> Chris opr VE7HCB

Hi Chris,

The only difference in Window line and true ladder line is the method that
is use to separate the two conductors.  Window line is manufactured by
embedding the two parallel conductors in PVC or Some other plastic and then
cutting windows in the insulation to reduce the detuning effect of rain or
wet conditions and it also make the line less prone to wind loading.

True open wire line usually has the conductors held apart by some type of
spacer such as wood, plastic I've even used clothespins before.. the
impedance of the Line is a result of wire size and spacing distance.  300
ohm line is usually encased in solid poly  or pvc. it is ok when dry but
maybe as lossy coax when wet..
hope this is of some help to you
73, Dave

P.S. as someone has already mentioned keep the line about 3 times the
distance between conductors away from conducting surfaces and you should be
all set..




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