[net.ham-radio] arrl propagation forecast bulletin nr 34

rjr@mgweed.UUCP (Bob Roehrig) (08/22/84)

qst de k9eui
hr propagation forecast bulletin nr 34  from arrl headquarters
newington ct  august 20, 1984
to all radio amateurs bt

the solar flux fell steadily after august 10, reaching a low of
74  on  the  19th.   the curve was similar to that for the same
point in the previous solar rotation four weeks ago. the low of
74  was last reached on july 20, but we have to go back to july
1977, to find solar flux levels that  low.   only  slight  flux
changes are expected until early september.

we are presently at the seasonal low point of the  year  for  f
layer  useable frequency in the northern hemisphere.  the daily
muf will be rising slowly during the balance of  august.   high
latitude  propagation  is reappearing on 21 mhz and 28 mhz will
be coming to life in early september.  the seasonal  peak  will
come  in  late  october with optimum conditions on all dx bands
prevailing through early december.  f layer dx  on  50  mhz  is
unlikely for the balance of solar cycle 21.

geomagnetic disturbances and generally poor propagation on  all
dx bands are expected august 24 through 26 and 28 through 31.

american sunspot numbers for august 9 through 15  were  between
15 and 32 with a mean of 25.1  ar