In a message dated 98-12-25 10:13:05 EST, you write:
<< Everything I've read indicates signal levels drop as frequency is moved
further below the MUF, and the strongest signals occur just below the MUF.
It is in the Antenna Engineering Handbook section on propagation and also
in other engineering textbooks. They lay the blame to increased absorption
as frequency is decreased below the MUF.
Is that incorrect in some way? >> Tom W8JI
No doubt correct on a cyclical basis, but not predictive short term so
certainly there are other determning factors relating to D layer (and other)
apsorption. One week ago, Thursday and Friday nights, when North American
had very good 160M conditions to Europe, the solar flux was 141-146. The last
several days the SFI has been around 139 and as low as 129. Conditions so far
this year appear down from last year at this black hole location in Colorado.
Doug Allen W0AH
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