>I think poor propagation tends to reduce log submissions by the
>causal guy - who might only make a handful of contacts during poor
>conditons but I think there are other forces.
>Namely high sun spot activity.
>Since 1996 the sunspots have been on a steady increase.
>This is almost an exact mirror of the decrease in VHF log submissions.
- K5TR
Interesting observation and graphs. I think George is on to something.
Some experts believe high solar activity diminishes mid-latitude Es
propagation. Thus, the best "years" for Es may be during the solar minimum.
Others, such as Pat WA5IYX(who has kept meticulous Es records for many
years) think that Es propagation has it's own "6 - 7 year" cycle that is
independent of the solar cycle. On a "day to day" basis, I have observed
high geomagnetic activity tends to suppress mid-latitude Es.
http://home.swbell.net/pjdyer/iyxfmsum.htm
However, even in a "poor" ovrall year for Es, the June VHF QSO Party can
have great propagation. In 1992 there were only 1560 minutes of Es recorded
in June, compared to 3405 minutes for June 1987. But many of these were the
contest weekend.
The "high sunspot activity" theory does not explain why log submissions are
down for the Sept. and Jan. VHF contests, as these are not "Es driven." High
Solar activity and flux should help the Sept and Jan. contests. It causes
geomagnetic storms with aurora and occasionally F2 on 6 Meters. Sadly, the
Sept. 1999 and 2002 VHF QSO Parties missed big auroras by one weekend. The
Jan. 2002 VHF SS had some 6 Meter F2, but not nearly as good as the weekend
before or after the contest. Maybe the ARRL just picks bad weekends for the
VHF contests!
- Jon N0JK
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