ad7i@houxp.UUCP (10/18/83)
qst de ad7i hr propagation forecast bulletin nr 42 from arrl headquarters newington ct october 17, 1983 to all radio amateurs bt two of the largest active areas seen on the sun in recent weeks brought the solar flux to a two month high of 140 on october 13. the first of these areas will disappear around the west limb by october 18 and the other is only a few days behind it. thus we see the solar flux dropping sharply, to 112, on the 16th. a reversal and a gradual rise are expected after about the 20th. fairly high geomagnetic activity has kept propagation to better than fair on all circuits traversing the higher latitudes. this will continue, except for brief periods of good conditions centered on october 20, 27, and november 1. the falling off of high latitude muf with decreasing solar activity is apparent from the propagation charts in qst for october, pages 66 and 67. the muf will continue high on north south paths, and to a lesser extent on all transequatorial circuits. the next six weeks or so will bring the highest muf and the most favorable dx con itions of the entire year, for a given level of solar flux. american sunspot numbers for october 6 through 12 were between 81 and 133 with a mean of 102.3 ar