> Are there any issues with running 450 ohm ladderline in PVC pipe
> underground? True open wire line would probably be best (like W7FGs), but
> I'm not sure how to "discretely" bring it back to the shack.
There are problems with that. A few years ago, I measured the loss
in ladder line in buried PVC pipe. I don't have that data handy, but
the loss increase is very substantial.
As I recall, placing the line inside PVC and then burying the pipe
for ten feet caused loss to exceed that of even very small coaxial
cables. There is substantial energy outside the area of the
conductors in a balanced line, and unless you can suspend the
line several conductor spacings (several inches) away from dirt you
will likely find you have a nice load resistor.
Of course the attenuation depends on the distance the line is
buried, what the soil is like, and the spacing from the soil to the
line...but I could even measure additional loss just from the PVC
pipe with the line and pipe in air!
Unless you can put a tuner at the antenna and bring coax into the
house, you may not have made a good bargain.
73, Tom W8JI
W8JI@contesting.com
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