Propagation News – 31 January 2016

Solar activity was a little more settled last week. The solar flux index was in the range 104-113 and the K index was mainly around one or two later in the week, after reaching four on Sunday.

This week the solar flux index is predicted to remain in the range 100-118, with lower activity on Friday the 5th and Saturday the 6th. The K index will be mostly settled, but possibly reaching four on Tuesday or Wednesday.

During this past week the noon critical frequency as measured by the Chilton Ionosonde reached 7.5MHz on Wednesday, offering a maximum usable frequency over 3,000km of about 27MHz. Ten and twelve metres have shown some activity with Bob, VP8LP on the Falkland Islands making an appearance at times.

Staying with the South Atlantic, the VP8SGI DXpedition should hopefully be on the air this week from South Georgia Island. On 7MHz and 14MHz, the best times for working them will be on 40m after midnight and 20m in the late evening and early hours of the morning.

During daytime, all the upper HF bands may offer opportunities, with even the possibility of a 10m opening from around 1000 to 1500 UTC. The optimum band, with a 90% probability of an opening, is 15m during late morning.

VHF and up propagation news

The hoped-for tropo didn’t materialise last week and the charts look very unsettled again. Later in the week one of the weather models predicts a small high in the cold air over northern Britain, but others are less convinced and maintain a much larger high near the Azores. Any useful ridging from this extending into the continent to give some tropo across the Mediterranean, France and Iberia is sadly just out of reach from the UK.

The Moon reaches minimum declination on Friday so we will have short moon windows and low elevations with losses still quite high.

We are still in the early-year minimum of random meteor rates, so persistence and early morning activity is still the order of the day for meteor scatter operators.

Overall then, it is not looking promising for any significant tropo, but perhaps other modes will come to our rescue like rain scatter on the GHz bands or possibly aurora. This is perhaps a good week to try some satellite QSOs if you want to keep your VHF and up QSO rates ticking over.

Category: GB2RS Propagation News