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Old October 21st 09, 01:39 AM posted to rec.radio.amateur.homebrew
brian whatcott brian whatcott is offline
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First recorded activity by RadioBanter: Jul 2009
Posts: 48
Default The dish problem

raypsi wrote:

Hey OM

If I look at the node of a source of 20mW and connect 10 wires to that
node with equal loads, I will have 2mW going down each wire. No matter
how I try and add them up I can't get more than 20 mW.


Correct.

Now I take a 20 mW isotropic emitter, now you're saying I feed a dish
with that 20mW emitter through a feed horn and now all of a sudden I
have gain, I have more than 20 mW?


Not exactly, I am saying you have a gain in power DENSITY
i.e watts per sq meter. In a desired direction only, naturally.

Like when you use a magnifying glass to collect the Sun's power into a
small spot.

73 OM
de n8zu