Hi Rick,
My first example is why NVIS can be useful. I often can't hear stations
150 miles away on 160 meters using my TX vertical, but they are booming in
on my pennant that has a much better response to higher angle signals (I
could definitely generate more points in a 160 meter contest if I had the
option to switch to an NVIS TX antenna at times). We can deal with fading,
phase cancellation at times, etc. in our hobby, but in the AM broadcast
industry they want to preserve signal and audio quality as much as possible
all of the time so it's really a different situation.
73,
Don (wd8dsb)
On Sun, Mar 1, 2020 at 10:26 PM Richard (Rick) Karlquist <
richard@karlquist.com> wrote:
>
>
> On 3/1/2020 6:47 PM, Don Kirk wrote:
> > Hi Rick,
> >
> > One more comment. I believe AM broadcast stations try to avoid phase
> > cancellation between skywave and ground wave, and therefore they try and
> > avoid antennas that have a high angle lobe. I'm pretty sure that's why
> > the AM broadcast stations that tried such things as a 5/8 wave length
> > radiator determined that this caused phase cancellation problems between
>
> I think you have just made my argument for me. NVIS antennas don't
> work for BCB stations. What is different about ham stations such
> that NVIS should work on 160 meters?
>
> Rick N6RK
>
>
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