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Re: todays math problem



w7lrd@juno.com wrote:

> Hello
> Bob has two dishes, dish 1 is 1959 square inches. Dish 2 is 791 square
> inches.  So dish 1 is about 2.5 times larger than dish 2.  Bob thinks
> dish 1 should be 7.5 db better than dish 2, that's 2.5X3db, or maybe a
> little over one S unit. Is Bob right?

Nope!

I have not dug out the calculator (and I'm not awake enough to do it without
it), but dish 1 is about 50 inches in diameter and dish 2 is about 32 inches
in diameter.  With all else being equal, doubling the diameter results in 6
dB, so going from 32 to 50 inches diameter will be something less than 6 dB.

73
-----------------------
Jim Walls - K6CCC
k6ccc@amsat.org
http://home.earthlink.net/~k6ccc/
626-302-8515    FAX  626-302-7501
AMSAT member 32537 / WSWSS member 395
To send me PGP encrypted E-Mail, use:
http://home.earthlink.net/~k6ccc/PublicKey.html


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