ad7i (12/29/82)
qst de ad7i hr propagation forecast bulletin nr 52 from arrl headquarters newington ct december 27, 1982 to all radio amateurs bt from a high of 279 december 10 the solar flux dropped to 156 by the 21st. it then rose to 176 but was back to 172 on the 27th. it is expected to move slightly lower before beginning what should be a considerable rise at the years end. the december average will be about 178, the highest since march. these statistics show cycle 21 maintaining quite high activity for more than four years. dx work has been possible on 50 mhz since late in 1978, a record that might stand for a long time. sunspot numbers and the solar flux have been mostly above base figures used for the qst propagation charts, so the muf has been higher than the charts predicted, much of the time. recent high solar activity has not been an unmixed blessing, as frequent solar flares and high geomagnetic activity have increased signal absorption on paths that cross or paths near the auroral zone. only about 5 days this month were really good for hf dx. conditions were improving as this bulletin was issued. propagation should be generally good through the end of december, and again around january 3 and 10 to 12. except when the wwv k index is 3 or higher, the f layer muf will tend to be above that shown in the qst charts. the timing of daily muf on a given path is based mainly on sun position, d this factor should follow the charts closely, regardless of flux levels. american sunspot numbers were not available at bulletin time ar