Thread: What exactly is radio
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Old May 3rd 10, 06:03 PM posted to rec.radio.amateur.antenna
Richard Clark Richard Clark is offline
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Default What exactly is radio
On Mon, 3 May 2010 10:30:26 -0500, (Richard
Harrison) wrote:

"To the OP, heat is not electromagnetic radiation."

Physics books disagree with Pat.

Hi Richard,

The discussion of heat is more a metaphysical concept because it is
confused by our senses.

Entropy demands that everything inexorably cools by dissipating its
energy (heat) into the void of cold space. Hence, everything radiates
(and yet we spend very little time writing about it, except for Art).
A good deal of this entropic radiation is like waiting an infinite
time for a circuit with infinite-1 Q to stop ringing.

The sun burns bright in the cosmos, but the greater part of the cosmos
is unheated by the sun even though all of the cosmos is illuminated
(radiated) by the sun.

Direct observation 1: Put two plates out in the noon sun but
undisturbed by the motion of air. One plate of metal, the other of
glass. Which gets hotter? Same amount of radiation from a known heat
source, but clearly different results in heat.

Direct observation 2: Shine (radiate) an IR LED onto the back of your
hand, or onto your forehead (an excellent heat detector). What do you
feel? At some IR wavelengths, your head is as translucent as an
architectural glass brick.

73's
Richard Clark, KB7QHC
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