SARL News reports that it's the peak of the Sporadic-E season in
South Africa and says that, for those of you who have never experienced a
strong Sporadic-E opening on 50 MHz, you are in for a very exciting
surprise when it happens.
Unfortunately Sporadic-E openings cannot be
predicted and unless you monitor a distant beacon or FM broadcast
station when it happens, you would not normally be aware of the
Sporadic-E opening. The beacon that you wish to monitor must be outside
the skip distance of about 600 km on 50 MHz or 900 km on 144 MHz.
A Sporadic-E opening first appears as a weak
fluttery signal and in minutes it increases in strength and the flutter
changes to slow QSB. The Sporadic-E signal could often peak well over S9
plus for a half an hour or so, before rapid QSB starts again and it
finally disappears.
Sporadic-E is normally a north/south event in South
Africa, but Cape Town and Port Elizabeth have worked each other on 50
MHz Es when both were beaming north. In the past many Sporadic-E
stations have been worked many times from Division 1 to Divisions 5 and 6
or from Division 2 to Division 6 and Namibia on both 50 MHz SSB and FM
mostly in the mornings. But the most memorable Sporadic-E opening
occurred on a Saturday afternoon in January on 50 MHz between Port
Elizabeth, Windhoek and as far north as Tsumeb. This Sporadic-E opening
lasted almost three hours with S9 plus signals and almost no QSB.
ZS6DN ran two beacons from Irene, one on 50 MHz and
the other on 144 MHz. On a few occasions these two beacons were copied
via Sporadic-E propagation in Port Elizabeth and signals could be
compared with each other. The 50 MHz beacon signal was always the
strongest, lasted the longest and with less QSB.
There are still a few Sub-Saharan Band 3 television
stations on the air with FM sound channels around 53,750 MHz and could
often be heard around midday during the Sporadic-E season. Sporadic-E is
an ionospheric propagation and is not polarized
TNX Southgate
