Hi,
In the past, there have been a lot of comments about not using water
pipe as a mast. I don't want to be unnecessarily argumentative, but those
comments do not agree with my experience. So, since the general subject has
come up again, perhaps those of you with this knowledge can inform me as to
why the apparent discrepancy between what I hear and what I've experienced.
Tower #1: 2 element Cushcraft 40 meter yagi at top of tower
4 element Cushcraft 20 meter yagi 7 feet above it
mast is 2" schedule 80 water pipe
tower height (without antennas) is 99 feet
Tower #2: 5 element HyGain 10 meter yagi at top of tower
5 element HyGain 15 meter yagi 7 feet above it
mast is 2" schedule 80 water pipe
tower height (without antennas) is 83 feet
Both of these towers have survived Hurricane Gloria, where 100 MPH winds were
actually recorded about 10 miles away, and Hurricane Bob which I would guess
actually hit my location with 70 or 80 MPH winds. The guesswork with BOB is
partly done by use of weather reports, and partly by personal observation.
I remember how far the 75 foot high pine trees bent in 100 MPH winds (and I
hope I don't have to experience that again!). We also experienced a
particularly bad Northeaster about 1993, during which we had several hours of
100 MPH winds, which remained in one direction (as opposed to Gloria, from
which we were hit twice from opposite directions due to the eye passing over
us).
I am located about 10 miles air distance from Plymouth Harbor in
Massachusetts. (Perhaps you could tell me the wind figures for this area
Steve K7LXC?)
There has never been any damage to any of my masts during these and
numerous lesser storms of 40 or 50 MPH. Any ideas as to why not?
73, Dave Clemons K1VUT
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