On Feb 22, 3:52 pm, "K7ITM" wrote:
With regard just to your last question, atmospheric (mainly from
lightening around the world), galactic, and typical man-made noise are
all much higher--40dB or more, usually--at 1MHz than at 100MHz. You
need signals above the noise for practical communications.
(Bandwidths also enter into the picture, but I believe the noise is
the key issue.)

Cheers,
Tom

Thanks, Tom! I did not know about this noise factor in this lower
frequency range. In a way, if I were operating at 100MHz using AM,
then I should be able to work with lower field strength values?