calle.jonsson@sverige.nu wrote:
> This evening condx into ZL/VK were amazing. VK3AMZ peaked 599, VK3ZL
> nearly the same etc. ZL3IX had a better signal than ever.Best VK evening
> in many years! The A index was very high. During my years on 160 I have
> never been able to figure out the relation between condx and A-index. Is
> there a relation at all?
> 73 Carl/SM6CPY
>
>
>
Hi Carl,
I am an engineer, not a physicist, so I do not understand the complex
algorithms that govern ionospheric propagation. I have read many
theories from other people though. I have come to the conclusion that
mankind has not yet mastered the art of predicting when condx will be
good or bad on Topband. The person who comes the closest is probably
Bob NM7M, who is a physicist.
One thing I have noticed from my own experience, is that the A index
does not seem to make much difference unless there is an accompanying
auroral disturbance, when propagation across polar regions
deteriorates. Living in SM, you will have noticed that. If the signals
between you and me were following a skewed path yesterday, the aurora
may not have had its usual effect.
I have also noticed that solar flux values in the 80-90 region seem to
give better propagation than when they are at 70 and below. Yesterday
the flux value was 85, and I'm sure that contributed to the improved
condx. I am told that the flux needs to be at least around 90 for the
E-F duct mode to be supported.
All experienced Topbanders just know that you have to try as often as
possible, and then one day you will be successful. It took 4 winters of
skeds before I finally managed a QSO with Bernie ZS4TX, and, to this
day, I have no idea why it finally happened in July 2006.
73, Greg, ZL3IX
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
|