rjr@mgweed.UUCP (Bob Roehrig) (07/24/84)
qst de k9eui hr propagation forecast bulletin nr 30 from arrl headquarters newington ct july 13, 1984 to all radio amateurs bt the solar flux fell to a seven year low of 74 on july 20. the most recent 74 had come july 19, 1977, when cycle 21 was only one year old. the occasional reappearance of such low solar flux numbers should not be taken to mean the end of f layer dx on our bands above 14 mhz for the next four years, however. the flux was back up to 84 on the 21st, and considerably higher values can be expected occasionally through at least 1985, and possibly longer. the very poor conditions during july were mostly the result of severe geomagnetic disturbances. the earths magnetic field is expected to be less active through the rest of july, and into early august, so there should be a general improvement in signal strength and quality on all dx frequencies. watch wwv for k indices of 2 or lower indicating improved propagation in the higher latitudes of the northern hemisphere. the k index was 3 or higher almost continuously july 11 through 21. this summer has been a disappointment for users of 28, 50 and 144 mhz. scattered e layer openings will continue through early august, but less frequently and over smaller areas than is normal for the summer season. american sunspot numbers for july 12 through 18 were between 13 and 48 with a mean of 29.0 ar
rjr@mgweed.UUCP (Bob Roehrig) (07/31/85)
qst de k9eui hr propagation forecast bulletin nr 30 from arrl headquarters newington, ct july 28, 1985 to all radio amateurs bt the solar flux rise predicted last week began 2 days earlier than expected. after 6 days at 69, ending july 24, the solar flux rose steadily, reaching 79 on the 28th. two minor sunspot groups came around the east limb of the sun last week. the second of these is low on the sun, giving rise to speculation that it may be a forerunner of cycle 22. an earlier low latitude spot was visible for only 4 days, beginning july 17. it did have little effect on the solar flux level for its short life. the area of the sun responsible for the flux peak of 101 on july 9 will be in view again about august 1. it is too early to tell if it will be of major importance this time around. a broad peak somewhat below 100 is a fair guess, for about august 4 to 8. more on this next week. sporadic e layer ionization seems late in reaching really interesting proportions this year. it is still showing up almost daily, and may have some surprises left. do not rule out transatlantic dx on 50 mhz. it has happened in august before, and the best e skip was late in starting this year. for those interested in much lower frequencies, the best propagation is likely after about the middle of august, when the solar flux is expected to be at its lowest for the month. atmospheric noise will remain troublesome on the low bands much of the time until early fall. american sunspot numbers for july 18 to 24 were between 8 and 18 with a mean of 11.1 ar