rjr@mgweed.UUCP (Bob Roehrig) (05/31/84)
qst de k9eui hr propagation forecast bulletin nr 22 from arrl headquarters newington ct may 27, 1984 to all radio amateurs bt the solar flux dropped below its level at the same point in the previous solar rotation on may 21. it fell steadily through the past week, reaching 117 on may 27. this was 66 points below the april 29 peak of 183. remnants of the large sunspot groups seen in late april are coming into view again, but they appear to have faded markedly in both number and size. coming in early summer, this quieting down of exceptionally active solar areas will not affect hf propagation severely, but similar losses next fall would cause significant changes in the hf dx picture in the direction of lower muf and longer skip on our lower dx frequencies. conditions were generally poor in the last week, mainly the result of frequent solar flares. propagation was improving at bulletin time, but this will not last. high latitude propagation will be no better than fair may 29 through june 2, but it will improve june 3 to 5. seasonal e layer activity will be common on 28 and 50 mhz, and the likelihood of 144 mhz e skip will improve during june ar
rjr@mgweed.UUCP (Bob Roehrig) (06/04/85)
qst de k9eui hr propagation forecast bulletin nr 22 from arrl headquarters newington ct june 3, 1985 to all radio amateurs bt may was interesting for propagation watchers. the solar flux peaked at 93, one point below the high for the year to date. the low was 68, on may 31 and june 1. the most recent 68 before these came in july, 1976, the first month of cycle 21. with this wide range of flux values, one would expect high levels of geomagnetic activity, but the may average for the a index was only 10.6. this is one of the lowest in the entire cycle to date. sporadic e skip is increasing markedly on 28 and 50 mhz. this is not yet the high density variety that will make for very short skip later this month, but it brought the 10 and 6 meter bands back to life, as word got around. no 144 mhz skip has been reported yet, but conditions more favorable for this will be showing up later in june, and in july. the summer e skip is not directly related to high solar flux or sunspot numbers, and the timing cannot be predicted accurately. transatlantic contacts were made fairly often in the low years of cycle 20, mainly in june and july. the most likely time appeared to be mid morning, eastern time, but evening openings were observed. these would be most favorable for 50 mhz transatlantic work as the european amateurs having 50 mhz permits are mostly restricted to after 2000 hours universal time. 100 british permits have been issued, and at least 25 norwegians now have similar authorization. other countries are likely to be represented as tv is gradually moving to higher frequencies. american sunspot numbers for may 23 through 29 were between 0 and 27 with a mean of 11.7 ar