Depending on the antenna, you do NOT need a thrust bearing with your system.
A lightweight antenna like an A-3 simply needs something to keep it aligned
in the "cone top hole" if you are using a skinny mast. However, if you are
using one almost the diameter of the hole and have a low square footage
antenna, mount the rotor, mount the antenna and don't worry about the
A good "hole aligner" can be made from a piece of hard wood bolted to a
shelf, or take two 2-inch toilet flanges to make a "sandwich" around the
A small piece of 2-inch PVC hold them together and they will make a pretty
good t-bearing for small antennas.
I've used this method for ten years on small tribanders, and 6 element 10
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