Propagation News – 7 May 2017

| May 5, 2017

Last week saw the solar flux index in the mid-70s with only one sunspot group visible, slap bang in the middle of the disk. Conditions were more settled geomagnetically with the K index actually resting at zero at times on Wednesday and Thursday. This was due to a lack of coronal hole activity, although one did become almost Earth-facing on Wednesday, which meant there was a chance that a high speed solar wind stream could possibly hit the Earth around Friday 5th May.

The settled conditions helped the bands a lot with reports of Pacific and Alaskan openings from the UK on 20m in the mornings. However, maximum usable frequencies over a 3,000km path generally stayed around 14MHz, although there were occasional openings on the higher bands.

Sporadic-E openings should soon start to make an appearance, which will add some interest to otherwise flat bands. The C30P 10 metre beacon in Andorra has already been heard on 28.256MHz. A link to a full beacon list can be found on the RSGB website by searching for “HF Beacons”

Although normally associated with six and 10 metres, the effects of a Sporadic-E event can often be seen from 7MHz upwards.

Next week, the solar flux index is predicted to remain in the mid-70s and geomagnetic conditions will be mainly settled.

As we said earlier, it’s May, and at last the Sporadic-E season is under way! There have been several openings across Europe and some paths hooking into parts of the UK, especially on 10m and 6m. The general rule for operating this mode is to start checking the beacons and clusters for signs of activity. As well as 10 metres, a six metre beacon list can also be found on the RSGB website.

It is often the case that the longest DX paths are when the band first opens, since the Sporadic-E layers gradually descend with time. The peak times are late morning and late afternoon/early evening.

We also have the chance of some Tropo next week with a ridge of high pressure over the country. The best paths appear to be oriented down the length of the country, and beyond over Biscay to Western France and northern Spain.

Most models suggest the high declining to leave space for low pressure to develop towards the end of the week and perhaps some rain scatter on the GHz bands.

Moon declination goes negative today and losses are high as we approach apogee on Friday, so it is a week to concentrate on Sporadic E for DX opportunities.

The Eta Aquarids meteor shower is under way and should have peaked early Sunday morning, but continues through to the 20th of May. But remember that for the Northern hemisphere, the radiant is low in the sky.

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

Category: GB2RS Propagation News