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
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