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Old July 23rd 05, 03:02 AM
Roy Lewallen
 
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Richard Fry wrote:
"Roy Lewallen" wrote:

As I'm sure you know, AM broadcast antennas intentionally radiate
very little sky wave, and that's what amateurs need for communication
beyond a few miles. Some care must be used in comparing MW
broadcasting requirements and characteristics with amateur
HF communications.


__________________

AM broadcast station verticals have very significant energy at elevation
angles that can be propagated by skywaves. As I'm sure you know, Class
A AM broadcast stations have an extended geographic service area served
exclusively by their nighttime skywave--many times more area than is
served by their surface wave, in fact.

Richard Clark's statement did not limit his conclusion to amateur HF
communications.

RF


I'm sorry, I stand corrected. Extended coverage AM stations do indeed
produce significant sky wave as you've pointed out. I was thinking only
of suppression of high angle sky wave radiation to avoid fading.

And you're also correct about Richard Clark's statement. Perhaps he is
indeed attempting to do some MF broadcasting to his local area -- I just
assumed he wasn't.

Roy Lewallen, W7EL