[50283] in North American Network Operators' Group
Re: Sunspot Activity & Radio Blackouts
daemon@ATHENA.MIT.EDU (Mike Lewinski)
Wed Jul 24 14:26:22 2002
Date: Wed, 24 Jul 2002 12:25:33 -0600
From: Mike Lewinski <mike@rockynet.com>
To: nanog@merit.edu
In-Reply-To: <20020724051113.85690.qmail@web103.bizmail.yahoo.com>
Errors-To: owner-nanog-outgoing@merit.edu
--On Tuesday, July 23, 2002 10:11 PM -0700 Andy Ellifson
<andy@ellifson.com> wrote:
> **** ( CORRECTED ) MAJOR SUNSPOT ACTITVITY ****
I passed this on to a neighbor for comment wrt 802.11b. His response
appears below:
> These blackouts generally affect communications in the HF (high frequency)
> range. This means that frequencies below about 30-40Mhz will be affected.
> The reason is that the F layers of the ionosphere are used to "skip"
> signals for long distance communications. The solar storms cause massive
> disturbances in the ionosphere which cause this "skip" effect to shut
> down. It is actually impressive to listen to by virtue of the total
> absence of normal noise, or any other signal, on these bands of
> frequencies. These frequencies are used, on occasion, for extremely low
> speed commercial/military digital communications (110 baud).
>
> This should have no effect on us. The R3 classification will shut down HF
> radio communications for a bit, but the G2 geomagnetic classification is
> not too bad and should not affect the power grids. Severe geomagnetic
> storms can shift the magnetic poles by many degrees.
>
> There are many places to get more information about sunspots. Being an
> amateur radio operator who likes HF communications, I have a bit of an
> interest in the topic.
>
> The most succinct monitoring and information site I have found is run by a
> group of short wave listeners in the Netherlands:
> http://www.dxlc.com/solar/
>
> Many of the measurements used are taken in Boulder (Boulder K index). Nasa
> usually has some great photos of the big CMEs/Flares
