X Flare

[pwdrive]

X Flare: X1.4 magnetude is still affecting 40 meters as I write, totaly dead a short time ago.

Lawrence.

[Mark R]

Lawrence, for those that do not know (me aherm) where do you get this kind of information?

cheers Mark

[Robert Darwent]

Hi Mark,

I use the following site;

http://www.spaceweather.com/

But Googling 'Space Weather' will throw up many more equally as good.

Regards

[Mark R]

Robert,
Thanks for the link, but forgive me for being really dim here..........how does solar activity interfere with radio reception?

keep it simple please to begin!

cheers Mark

[Robert Darwent]

Hi Mark,

When a solar flare erupts that is pointing directly towards the Earth (as with the X-flare being reported) it sends a cloud of fast moving charged particles straight at us. It usually takes between 24 to 48 hours to reach us after the eruption is seen visually though.

When the flare arrives it collides with the Earths magnetosphere (essentially a protective 'umbrella' created by the Earth's magnetic field) which deflects the charged particles towards the poles and gives rise to aurorae (Northern and Southern Lights).

However it also collides with the Ionosphere, layers of charged particles always present around the Earth which short wave radio signals bounce off to reach around the globe. The flare basically saturates these layers for a period causing them to absorb radio signals rather than refract them back to the Earth, so effectively 'blacking-out' radio reception until the ionosphere returns to normal.

Obviously a lot more is going on than what I have described, but you get the rough idea I hope?

Regards

[Steve_P]

The sun and it's actions, regular and irregular, affect the earth's atmosphere. For example, the way that you pick up foreign stations after dark and, interestingly, during a solar eclipse. This is Sporadic 'D'.

Sporadic E and F go further. Sp.E. is mostly a summer thing and DX TV people work on it, as well as Sp F, which occurs during sunspot activity on an 11 year cycle.

Read this...

http://en.wikipedia.org/wiki/Radio_propagation

Cheers,

Steve P.

(Giving you the one-eye look...)

[Mark R]

Thanks Chaps a really good explanation.

Steve has an eye on me like Sauron.......... I shall post in the other thread.

cheers Mark

[pwdrive]

Lawrence, for those that do not know (me aherm) where do you get this kind of information?

cheers Mark

Hello Mark, I've been having my dinner....Your question seems to have been answered.
space weather com, solar ham com etc there are loads of others but space weather com is usually the one that is most up to date, there are many links on that site to the official organisations that study and monitor the space weather as it is called.
X flares are at the high end of the classification, preceeded by M class and C class etc. If they are earth directed then there effects will normalyl be noticed in the radio spectrum especially for regions that are still in daylight in the form of a full or partial radio blackout depending on the severity of the event
I am sure there are many that have been caught out by it's effects when working on radio receivers, me included but now with the advent of PC's and obsevatory sattellites it is easy to check as was the case with me late this afternoon, I had shut down a receiver to do some fiddling when I switched it back on some time later I went straight to the 40 meter band to do a reception check as I know from experience that the European broadcast stations that set the upper limit of the amature band start to come through quite strong at around 4.30 pm but when I tried I could only get an extreamly weak hetrodyne, subsiquent cruising of tjhe amature band returned ansolutely zilch it was then that I suspected a radio blackout, a quick check on the space weather revealed the X1.4 event so no problem.

It is beleived by many, including myself that the sun spot cycles can affect the weather, the effects of sun spots,solar flares etc is still to a certasin extent an unknow science.

Lawrence

[pwdrive]

http://www.swpc.noaa.gov/alerts/warnings_timeline.html

Mark, if you click on the above link it will show a plan of current events, click on the blue triangle it will show the warning issued by NOAA relating to that X Class event.

Lawrence.

[pwdrive]

Following on, here is a link to a series of basic articles on radio signal propagation, it also covers the effects of solar events etc on propagation.
For any newcomers to the hobby it is a relatively easy read:

http://www.radio-electronics.com/info/pr...basics.php

Lawrence.