On 10/24/01 8:32 AM, Tom Rauch at w8ji@akorn.net wrote:
>RCA spent a fortune on studying this, and they concluded 50-60
>1/4 wl radials acted like a solid plate. The key is to not let the open
>spaces exceed about .025 wl between wires. That even works with
>a screen reflector antenna!
I don't mean to disagree with Tom, whom I have the highest respect for,
but the math doesn't quite work out.
If you have 1/4 wl radials, you create a circle or radius 1/4 wl, with a
perimeter of pi/2 wl. (eg 2 pi r )
Now, pi/2 wl divided by 50 is pi/100 -- which is 0.0314159..., and pi/2
wl divided by 60 is pi/120 -- which is 0.02618. Close, but not quite
0.025.
That would tend to indicate you can have ultimate spacing a bit larger
than 0.025 wavelength -- perhaps as much as 0.030.
Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@arrl.net
Quote: "Not within a thousand years will man ever fly!"
-- Wilbur Wright, 1901
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