Dennis Schaefer wrote:
> "Schedule 40, etc" did not seem to be acceptable, and was sometimes
> referred to as "water pipe".
For years I have used Schedule 40 1.5" (1.900" OD) galvanized water pipe
for masts. I think there cannot be a problem if the antenna is within a
couple of feet of the top of the tower.
If I am stacking antennas such as my little Cushcraft 2 Element 40 which
is about 10-12 Ft above a 4 Element 20, I'll telescope a Schedule 40
1.00" galvanized water pipe inside the 1.5" one and drill and pin them
near the top with 1/2 inch bolt. This makes for a VERY heavy mast that
I think (no basis other than 30 years of no problems) will stand a lot
of wind/flex. The last time I checked I couldn't find Schedule 80 that
was galvanized. Besides the 1" inside the 1.5" appears to be stronger.
I would not put a very large antenna very far above the top of the tower
regardless of what mast I was using and I definitely wouldn't have an
installation that required that I worry about which way the wind was
blowing relative to the direction of the antenna...
Stan K5GO (Harrison, AR)
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