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About 15 years ago I built something like this using a Heathkit =
weather station. (This was the same project that used the Hoffman =
equipment boxes I mentioned in another post.)
The Heathkit unit provided digital outputs of windwpeed, direction, =
temp, pressure; third-party sensors provided relative humidity. I =
(actually, engineering students working for me) wrote machine code for =
Apple II's (!!!) to read the met data and record it; BASIC was too slow.
For tower control today, one could use a similar system sold by =
folks like Peet Bros. as advertised in 73. (www.peetbros.com). Bring =
the wind speed and direction from the serial port into a PC. Use peak =
speed or average speed over some user-selected time interval to trigger =
rotator, via PC, to turn mast into wind. If peak exceeds another higher =
threshhold, bring the (crank-up) tower down to a safer level. Mount =
the anemometer (wind-speed indicator) near the tower top; it won't do =
the mast much good to know how blustery it is on top of the garage. Use =
opto-isolators to connect the PC to the rotator controller if you're =
home-brewing this thing. =20
I would caution against using this system as an excuse to overload =
a tower. This ought to be used only to protect a properly designed and =
installed antenna system from damage in the event of unexpectedly high =
sustained winds. Also, don't assume the PC (and power grid) will be =
operating during hurricane/tornado weather. =20
Something to think about.
-Gene Smar AD3F
=20
-----Original Message-----
From: DavidC <davidc@bit-net.com>
To: Kurt Andress <ni6w@yagistress.minden.nv.us>; Roger Cox
Cc: towertalk <towertalk@contesting.com>
To: <towertalk@contesting.com>
Date: Tuesday, August 18, 1998 4:37 PM
Subject: Re: [TowerTalk] Projected area of Hy-Gain beams
>
>> Another thought about Roger's listing for the Hygain antennas. Think =
what
>you
>> could put on the tower if you always kept the smaller area pointed at =
the
>wind.
>> The differences are pretty dramatic for everything except the 10M & =
6M
>> antennas! 73, Kurt
>
>Now here is an interesting idea. What about a wind
>direction--sensor/limiter that would provide an indicator of =
directional
>wind stress, or actual rotor control in high wind conditions to prevent
>overstressing a tower?
>
>Would this not allow one to load heavier and only be directionally =
limited
>as high winds dictated? It would allow larger antennas on lighter-duty
>towers, would it not?
>
>Sounds like a new rotor control option, especially for areas plagued by
>high winds.
>
>Hmmm, the gearloose inventor in me seems to have broken loose of the
>restraints!
>:-) DavidC AA1FA
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