In a message dated 97-11-04 08:30:00 EST, AB5XPwrites:
<< For the 160 meter Contest in December we install a 1/4 wave balloon
vertical on a ridge in southern MS. We feed it with open wire line. A run
of about 700-800 feet. >>
Mike,
I have used balloon 1/4 wave vertical (WA7UQV kits) both at my house and at
field location. I use elevated radials ( 2 or 4 of them) at 30 or 40 ft.
using PVC pipe mast, or rooftop of the house. Radials (1/4 wave) are sloping
down to about 5 ft off the ground. Antenna has impedance of or close to 50
ohms, no need to feed it with anything but coax. The only problem I found
especially for contest is the F$%^& wind. I realized that this could be only
secondary antenna if WX is nice to me in the contest. Otherwise you are on
the mercy of wind, makes for very nervous operating in the contest. (Lost one
balloon and had to roll the second balloon down in CQ 160 m contest from Cape
Henlopen DE, ended up using two radials as 40 ft high inverted Vee. Hi Enough
of that.
Why are you feeding 50 ohm antenna with open wire feeder anyway? Use coax,
even 800 ft would have low loss on 160 if you need to go that far. It is
better to be close to TX antenna and use long coaxes for beverages if you use
them.
GL Yuri VE3BMV, K3BU
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