Can you link me to where I can get more info describing how to use the Dst
index ?
I'll also point out that A and K were low last night, but AU effects
lingered on here in IL. Even at 11 PM I had little low/mid band lat skip from
the usual super dominent clears.
----- Original Message -----
Sent: Wednesday, September 21, 2005 5:53
PM
Subject: Re: [IRCA] Tonight
Also the background x-ray solar flux is A9.7 and the Dst index is
a -4, which are more reliable indicators of good MF propagation band
conditions than the Ap and Kp indices.
Here are some general guidelines concerning
correlation of MF propagation indices to actual expected propagation
conditions.
1.) Dropping indices numbers are better.
2.) For medium frequencies a solar
flux under 150, under 100 better, 70 is best for E layer multi
hop.
Keep in mind though that the 10.7 cm
(2800 mhz) solar flux index is not a "reliable" gauge of ionization in our
atmosphere for F layer MF frequency refractions, as the energy of photons at
this frequency is to low on the order of one million times. However most are
used to solar flux and sunspot number and it's a hard habit to break. A better
indicator is the background x-ray flux. See #7 below.
3.) Solar flux of at least 100 for E
valley-F layer ducting mechanism.
4.) Previous 24 hour Ap index under
10, under 7 for several days consecutively is best.
5.) Previous 3
hour Kp index under 3 for mid latitude paths, under 2 for high latitude paths,
0-1 for several days consecutively is best.
6.) Energetic protons no
greater then 10 MeV (10+0) for 160/120 meters and no greater then (10-1) on MF
broadcast band.
7.) Background x-ray flux levels less than C1 for
several days consecutively for 160/120 meters and less then B9 for MF
broadcast band, A9 or less is best.
8.) No current STRATWARM alert.
9.) IMF Bz with a (positive number) sign, indicates a lesser chance of
high latitude path auroral absorption/unpredictable refraction or scattering
of MF RF signals, when the Kp is above 3.
10.) A -50 or better towards
a positive number Dst index during the recovery time after a geomagnetic
storm, as related to the Equatorial Ring Current.
----- Original Message -----
Sent: Wednesday, September 21, 2005
6:39 PM
Subject: [IRCA] Tonight
A=3! K=0!
Grey line approaching at 1000 mph!
Tonight's the night to put on the cans.
Jim Hannah
10307
Sangean 818, barefoot