Topband: mag-field still sick !

[Robert Brown]

Wolf,

Thanks for the posting; it's good to hear from you again.

During times of high geomagnetic activity, the solar wind can distort 
the high-latitude lines of force and carry E- and F-region electrons back 
into the magneto-tail, adversely affecting DX propagagtion (e.g., DF to 
W6) on long hops.  Also, auroral activity increases ionospheric absorption 
at lower altitudes in the auroral latitudes. 

When the solar wind abates, E- and F-region ionization returns slowly to 
the former equilibrium distribution, by upward diffusion of electrons and 
photo-production during daylight.  Because of density considerations,
there is a delay and the lower altitudes (and shorter DX hops) recover 
first.

So paths into the polar caps suffer these effects while sub-auroral and 
low-latitude paths are essentially immune.

73,

Bob, NM7M