Interesting topic
Rick
To your comment regarding close in signals on 160, have some thoughts here:
Agree on the 40 and 80 stuff. I use a low inverted Vee for local contacts.
Typically I can barely hear the locals on my vertical system (80). Very
dramatic difference in signal level.
On 160, I have also have a low inverted Vee (65 ft) and a 4 square of inverted
L elements. It is very apparent the inverted L array does carry horizontal
(high angle) polarization as it works well with both low and high angle stuff.
I still find the close by stations are sometimes better on the inverted Vee
(100 miles) but vertical system is not too far behind.
My conclusion is the same effect we see on 80 (vertical vs. horizontal) is
nearly the same as 160 except because my vertical system still has some high
angle takeoff, the difference is not as pronounced. Certainly confirms the top
L portion generates a fair amount of high angle. It’s the best I can do at
this place.
Just one man’s story.
Regards,
Mark, K1RX
603-231-8965
> On Mar 2, 2020, at 12:13 AM, Richard (Rick) Karlquist <richard@karlquist.com>
> wrote:
>
>
>
>> On 3/1/2020 7:44 PM, Don Kirk wrote:
>> 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)
>
> OK, Don, that's a fair argument.
>
> I should be able to do some simple tests on the BCB
> comparing my car radio with a whip to a pocket radio
> with a ferrite rod antenna. The ferrite rod antenna
> is omnidirectional wrt to elevation on account of
> symmetry. At sunset, the SF Bay Area stations reduce
> power and become hard to hear 70 miles away here in
> Sacramento county on the car radio. My Sangean radio
> should pull these in a lot better. I will do some A/B'ing.
>
> I completely agree that for 80 and 40 meter contests,
> vertical miss out on all the close in stations. I
> have 80 and 40 meter cloud warmers for SS, etc.
> I'm just not so sure that this happens on 160 meters.
>
> Rick N6RK
>
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