Vin, Kathy, et.al.
I doubt the Geomagnetic storm had much effect on 20m. Gemomagnetic
Storms have their greatest effect on 40m, manifesting as high levels
of QRN. Strong storms can affect higher frequencies, but the effect is
the same, increased QRN.
Kathy describes low noise and weak signals on 20m. Most likely this is
due to the fact that we are at the low point of the current solar
cycle. Solar flux has been running 75 +/- or so lately, barely enough
to charge the ionosphere for good daytime ops. The area of the
ionosphere of interest here is the "F" layer, it is charged by solar
radiation, and reflects HF signal back to earth. The F layer has its
greatest effect on signals 10MHz and above, up to 10m or so.
During evening hours, when the sun does not charge the ionosphere, the
F layer rises in altitude and becomes quite thin. Most of the radio
signal propagates out into space, leaving very little to reflect back
to earth to be detected by a receiving antenna.
Noticing that RFB was in the evening hours, I expect Kathy's
observations were a result of the ionosphere as I describe. As for the
loud PSK signals: Maybe those stations were close by? Or, maybe
running high power? (more signal to reflect back) I've observed many
people using 20, 30 even 100W or more for PSK ops as little as a year
ago. (I haven't worked any PSK in the last year. When I did, it was
never with more than 2 or 3 Watts)
A good primer on HF propagation can be found here:
http://sec.noaa.gov/info/Radio.pdf from NOAA/SEC. More educational
material WRT Space weather, radio propagation...etc. can be found
here: http://sec.noaa.gov/Education/index.html
A quick, and relatively inexpensive, way to determine the K2's
sensitivity is with the Elecraft XG2 signal generator, It has a 1uV
signal level on 80/40/20 suitable for MDS measurements.
73, Rod Ai7NN
On 8/21/06, Vin Cortina <[EMAIL PROTECTED]> wrote:
Cathy,
There was a geomagnetic storm recently which may be affecting things. Wait
...
----- Original Message -----
From: "Cathy James" <[EMAIL PROTECTED]>
To: <elecraft@mailman.qth.net>
Sent: Monday, August 21, 2006 10:15 PM
Subject: [Elecraft] K2 insensitive on 20...or is it?
...
> But when I attempted to look for QSOs in the recent Run for the Bacon, I
> not only found very few CQers on 20, it seemed that both their signals and
> the background noise (which of course would be lower on 20 anyway) were
> very weak.
...
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