rjr@mgweed.UUCP (Bob Roehrig) (05/01/84)
qst de k9eui hr propagation forecast bulletin nr 18 from arrl headquarters newington ct april 30, 1984 to all radio amateurs bt the last full week of april was an exciting one for solar observers. there were many major solar flares, causing numerous ionospheric fadeouts. the solar flux reached 183 on april 29, its highest level in 17 months. this was a poor time for high latitude communication on any dx frequency, but transequatorial propagation was quite good most of the time. this is the same area of the sun that produced fireworks at the end of march, but the level of activity was considerably higher this time around. the active areas are near the center of the sun as this bulletin is being prepared. there is nothing of significance east of these sunspot concentrations, so it seems almost certain that the flux will be dropping rapidly during the forecast week. propagation will continue unstable most of the time through about may 7, but good spring conditions will prevail for a week or more thereafter. solar flux values should be between 130 and 100 during the first week of may. several sporadic e openings have been observed on 28 and 50 mhz. there will be more and better times for this mode later in may, but the best and most widespread e skip is still a few weeks away. much is heard on 28 mhz these days about the expected demise of dx on that band. the decline in high latitude dx on 28 mhz is seasonal, and it would have occurred even with still higher solar flux levels than we have had in recent days. this band is still good for work into south africa, south america and the south pacific islands, but paths like that to northern europe will not be working regularly again until autumn. american sunspot numbers for april 19 through 25 were between 38 and 102 with a mean of 64.1 ar