1. Don't even THINK of using anything less than 3" PVC (or whatever
material) and 4"" is better. Three coax runs will look very lonely in a
3" or 4" pipe, but you will be happy you used a larger pipe when the day
comes to pull more cable through it. It costs little to do it now and will
save considerable frustration later.
2. Spend some time determining where the low point(s) are and provide holes
and drainage area under these points. No matter what you do, water will be
present in the pipe; some from condensation.
I had to dig up a run of 2" PVC and redo it (with 4" and better drainage)
not long ago. I had standing water in the pipe and could not change cables
in the old conduit.
Bill - W2WO
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