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Old April 30th 10, 03:00 PM posted to rec.radio.amateur.antenna
[email protected] greenpjs@neo.rr.com is offline
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First recorded activity by RadioBanter: Jun 2009
Posts: 18
Default What exactly is radio

On Fri, 30 Apr 2010 05:12:38 -0700 (PDT), Cecil Moore
wrote:

On Apr 30, 4:14*am, "Peter" wrote:
I know this group has some expertise on this subject and would appreciate
any constructive comment and suggestions regarding the attached article.


The two-dimensional Fig. 2-2 graph is confusing in that it could be
inferred that the E and H fields are 90 degrees out of phase in time
and are never zero at the same time. The E and H fields are in phase
in time as demonstrated by Fig. 2-4.

Hmmm. I'm no expert, but I thought they were 90 degrees out of phase.
It's the rapidly changing H field that creates the E field and vica
versa. If you look closely, Fig 2-4 also shows them 90 degrees out of
phase.

To the OP, heat is not electromagnetic radiation. Light and x-rays
are. You can heat something by pointing em radiation at it and
something that is hot gives off infra-red em radiation, but heat
itself is not em radiation.

Pat