http://www.solarcycle24.com/pictures/spots5.jpg

dave wrote:
http://www.solarcycle24.com/pictures/spots5.jpg



Thank you... and that's quite a photograph.

I dispute the generally-held opinion that higher sunspot numbers
mean "better propagation," though.

While the higher bands, say 7 MHz and above, improve -- the lower
frequencies tend to get shorter and absorption gets higher. This
bodes ill for 160 meters, for example, and 75 meters during the day
goes almost silent (though it may be better at night for short to
medium skip). And dramatic DX on longwave and mediumwave becomes
less frequent.

No matter what, though, it's interesting, and the clouds we cannot
see bring magic.


With my best,



Kevin, WB4AIO.
--
http://kevinalfredstrom.com/

Kevin Alfred Strom wrote:
dave wrote:
http://www.solarcycle24.com/pictures/spots5.jpg



Thank you... and that's quite a photograph.

I dispute the generally-held opinion that higher sunspot numbers mean
"better propagation," though.

While the higher bands, say 7 MHz and above, improve -- the lower
frequencies tend to get shorter and absorption gets higher. This bodes
ill for 160 meters, for example, and 75 meters during the day goes
almost silent (though it may be better at night for short to medium
skip). And dramatic DX on longwave and mediumwave becomes less frequent.

No matter what, though, it's interesting, and the clouds we cannot see
bring magic.


With my best,



Kevin, WB4AIO.

You need UV radiation to energize the upper atmosphere. Sunspots are
where the UV rays come from. It's in your Extra Class test.

dave wrote:
[...]

You need UV radiation to energize the upper atmosphere. Sunspots are
where the UV rays come from. It's in your Extra Class test.



Yes, I know about the ionosphere. But what I am trying to say is
that more radiation is not always "better." And there's always some,
even at sunspot minima.

For example, during the bottom of the solar cycle, 75 meters is
alive during the day, with stations heard many hundreds of miles
away with good signals. Near the top of the cycle, the absorption is
so high, you can hardly hear any stations at all daytimes on 75.


With all good wishes,


Kevin, WB4AIO.
--
http://kevinalfredstrom.com/

On Thu, 15 Jul 2010 11:41:53 +0000 (UTC), Kevin Alfred Strom
wrote:

dave wrote:
[...]

You need UV radiation to energize the upper atmosphere. Sunspots are
where the UV rays come from. It's in your Extra Class test.



Yes, I know about the ionosphere. But what I am trying to say is
that more radiation is not always "better." And there's always some,
even at sunspot minima.

For example, during the bottom of the solar cycle, 75 meters is
alive during the day, with stations heard many hundreds of miles
away with good signals. Near the top of the cycle, the absorption is
so high, you can hardly hear any stations at all daytimes on 75.


With all good wishes,


Kevin, WB4AIO.

I think that corona holes and the resulting solar windstream are the
biggest disruption to propagation. At least here in the higher
latitudes. We had an impact last night and the bands are in noticeably
poorer condition today even though the K index is back to 2 (5 last
night).

http://www.swpc.noaa.gov/rt_plots/kp_3d.html

Jim

On Thu, 15 Jul 2010 14:40:27 -0800, dave wrote:

wrote:


I think that corona holes and the resulting solar windstream are the
biggest disruption to propagation. At least here in the higher
latitudes. We had an impact last night and the bands are in noticeably
poorer condition today even though the K index is back to 2 (5 last
night).

http://www.swpc.noaa.gov/rt_plots/kp_3d.html

Jim

I can hear lots of noise very few stations on 20, not wall to wall
traces as would be normal this time of day. Seems to be slowly getting
stronger.

Seems to take about 2 days for things to get back to normal after
particle impact. I look at that "current auroral oval" map at:

http://www.spaceweather.com/index.html

If there is a white mist covering the midwest, its usually bad news
(like today).

Jim

wrote:


I think that corona holes and the resulting solar windstream are the
biggest disruption to propagation. At least here in the higher
latitudes. We had an impact last night and the bands are in noticeably
poorer condition today even though the K index is back to 2 (5 last
night).

http://www.swpc.noaa.gov/rt_plots/kp_3d.html

Jim

I can hear lots of noise very few stations on 20, not wall to wall
traces as would be normal this time of day. Seems to be slowly getting
stronger.