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Re: Once again: Realistic BBQ Dish Gain with OriginalDipole Feed, an



 I've had a BBQ dish up since day one. After the last round of BBQ dish vs
bigger solid dish war's, I broke down and setup a 36" x 39" offset PrimeStar
dish. I then constructed a Helix and a patch feed for it. Yes my d/l went
from an S-5 to an S-9 +, yes I can hear myself with 1 watt input (11 watts =
ERP of a 100), but the wind loading is definitely a big problem. We had a
very windy spring here on the east coast, gust's to 60 MPH on several day's.
This caused me alot of grief with rotor re-alignment on several occasion's.
I was outside watching my antennas (which are just 17' off of the ground and
observed a wind gust cause the rotor to turn without any power applied. It
made sort of a whirring noise. I'm sure this is very hard on the gears. I
went into my shack , turned on the rotor box and observed a 20 degree or so
azimuth change from my normal park position. Another problem is with my 5
year old fiberglass boom. The mounting point's at the dish are digging into
the fiberglass and causing the dish to change it's mounting position. This
is another case for using a metal boom, even if there is a slight loss of
signal. Anyway it might be a better idea to simply cover the BBQ dish with
screen , convert it to a circular feed via the Helix or patch feed. K5OE
converted a BBQ shaped dish to a round one then covered it with screen, see
his web site. I know this wind loading issue (solid same as screen covered)
has been discussed here before but I had my BBQ dish up with screen on it
and observed much less wind loading. None of the afore mentioned problem's
I'm having with the PrimeStar occurred.
 I, myself am going to experiment some more with the screen covered BBQ dish
with circular feed's. Also looking for a 8 foot plus dish to ground mount. I
would give the wind loading issue alot of thought......

 > 1.) Windloading - the BBQ has a LOT less windload than a solid dish.
> Jon
> NA9D

See you at Dayton.....
73 Jeff kb2m


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