Thread: Light,Lazers and HF
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Old September 11th 08, 04:16 AM posted to rec.radio.amateur.antenna
Roy Lewallen Roy Lewallen is offline
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Default Light,Lazers and HF
wrote:

Of course.

Everyone knows the gain of a parabola is directly proportional to
the size in wavelengths, or:

G=10*log k(pi*D/L)^2

Where G= gain in DB over an isotropic, k ~ .55 for most real parabolas,
D is the diameter, and L is the wavelength (wavelength and diameter
in the same units.

So a 2,000 foot parabola on 20m would have just about 58db gain.


Hm. I get 47.

Roy Lewallen, W7EL
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