Propagation News – Updated 14 April 2014

| April 11, 2014

Now the solar factual data for the period from Friday the 4th of April to Thursday the 10th of April, compiled by Neil Clarke on Friday the 11h of April.

Only four new sunspot regions were numbered during the period and all were small. Solar activity was at low levels with only a small number of C class solar flares taking place most days. However, on the 8th, activity declined to very low levels when no C class flares took place. Solar flux levels declined from 157 units on the 4th to 131 by the 9th. The average was 140. The 90 day solar flux average on the 10th was 154, that’s five units down on last week. X-ray flux levels declined slightly at first but by the end of the period had recovered back to B8 units. The average was B5 units. Geomagnetic activity increased to just unsettled levels on the 5th and again on the 7th. The most disturbed day was the 5th with an Ap index of 12 units. The average was Ap 6 units. Solar wind data from the ACE spacecraft saw solar wind speeds vary between 330 and 500 kilometres per second. Particle densities started the period at 41 particles per cubic centimetre but then declined to single figures by the 8th. Bz varied minus 9 and plus 10 nanoTeslas on the most disturbed day and between minus 2 and plus 4 nanoTeslas on the 10th.

Finally, the solar forecast for the coming week. This week solar activity is expected to continue at low levels but on some days activity could increase to moderate levels if a M class solar flare takes place. For most of the week solar flux levels should be in the 150’s. Geomagnetic activity is expected to be quiet for the first half of the week but by Thursday a small coronal hole could increase activity to unsettled levels. MUFs during daylight hours at equal latitudes should be around or slightly below 30MHz. From anytime now the daytime highs will mostly take place during the early evening, this will last till the autumn time. Darkness hour lows should be around 13MHz. Paths this week to Japan should have a maximum usable with a 50 per cent success rate of around 26MHz. The optimum working frequency with a 90 per cent success rate will be about 20MHz. The best time to try this path will be between 1000 and 1200 hours. You may find the long path slightly better and this will be at its best a couple of hours earlier.

And that’s all for this week from the propagation team.


We apologise that it was not possible to incorporate this information within the 13 April GB2RS News broadcast script.

Category: GB2RS Propagation News