Posts Tagged ‘Sporadic-E’

Ash scatter?

For the last week or so I have been using the K3 for WSPR on 10m to detect the signs of any Sporadic-E openings. Since the opening of May 3rd there has been nothing very exciting to report, though it has been interesting to see spots of stations previously never heard suddenly appear, often at good strength, as a patch of ionization materializes in just the right place.

What has been intriguing over the last few days is the consistent appearance of spots involving OY1OF throughout the day, often with stations in the UK but also with those in Holland, France or Germany.

The distance is too far, obviously, for the ground wave propagation that is often the only propagation reported between closely located stations. The spots are too frequent and too widespread to be Sporadic-E. And they surely cannot be regular F2 layer reflections, as the MUF in this part of the world at this point in the solar cycle is still far too low (the F2 critical frequency is around 4MHz according to the IPS Radiowave Propagation Center.)

Could it be scatter from the ash of the Icelandic volcano?

First 6m Sporadic-E contacts of 2010

I spent the morning building this constant current charging circuit on to the circuit board of the junk Motorola charger I bought on eBay. I also made a power lead so that it is powered by my K2 power supply, eliminating the need for yet another wall-wart. The charger was supplied with a UK type switched mode power supply rated at 12V 1000mA. In view of the “quality” of the charger itself it is unlikely that I would want to use the wall-wart that came with it for anything, but surprisingly when I tested it I couldn’t find any obvious interference. As I have said before, the electrical noise level here is so high that something would have to be pretty bad for me to notice it, but that was a device which I expected to be pretty bad.

As I was checking the bands for new unwanted noises I heard a CW signal on the 6m band. That turned out to be EB1EHO, whom I worked for my first Sporadic-E contact of the year. I spent an hour or so on the band and worked several stations on the west coast of Spain and one in Portugal, CT1ANO.

As you can see from the DX Sherlock map, the reflective Sporadic-E cloud appeared to be located somewhere over South Wales. I did hear a Scottish station working EA6/M0DLL on the island of Menorca. The DX was right down in the noise and not copyable on my dipole but might have been workable if I had a beam. So clearly there was Sporadic-E about elsewhere.

This opening was a nice treat for a Bank Holiday and I hope is an indicator of things to come this year.

Detecting Sporadic-E on 2m

We are entering the Sporadic-E season, the favourite time of the year for those who enjoy operating the VHF bands. As Roger G3XBM suggested today, more stations this year will be using WSPR on the 10m and 6m bands, so many openings may be detected that would otherwise be missed. I am WSPRing on 10m at the moment, and will probably move up to 6m later on once 10m starts opening on a regular basis.

However, my first love will always be 2m. From this QTH surrounded by hills Sporadic-E is the only type of propagation that allows me to work DX on that band. On 2m, Sporadic-E openings are much rarer because much smaller patches of the Sporadic-E clouds are dense enough to reflect signals at this frequency. This makes propagation between two points on 2m much more fleeting. A station can be 59+ one minute and gone the next, which makes it essential to keep QSOs short and sweet: report, locator, and name only if you are sure you have got the time.

Some people are planning to use WSPR on 2m as well, but because of the fleeting nature of propagation I am not convinced that the 2 minute periods of WSPR make it the most appropriate method of detecting propagation on this band. I think it might be more fruitful to monitor 144.8MHz which is the APRS frequency in Europe.

APRS packets take only a second or two to send, so you don’t need propagation to be good for two whole minutes to receive one. Packets do need to be received clearly, but the “strong or gone” nature of Sporadic-E on 2m suits that quite well. The main difficulty is knowing the location of the station that sent the packet you heard, since it could well be a digipeater retransmitting a packet sent from somewhere else.

There used to be a website that displayed a propagation map based on APRS packets received. But in the last few days it appears to have gone QRT, which is rather a shame. But if you are in a location that doesn’t normally hear much APRS activity, even just hearing a number of signals going “braaap” on 144.8MHz could be the alert you need that some unusual propagation is about.

If anyone has any other ideas on how to improve the detection of Sporadic-E on 2m without sitting in front of the receiver listening to band noise for hours on end I’d be interested to hear them. If you aren’t familiar with this mode of propagation and how it works and would like to learn more about it then there is an article about Sporadic-E on my website.

First sporadic-E of 2010

I heard a little bit of sporadic-E propagation on 10m this afternoon. Tuning around the beacon segment I heard the beacon DK0TEN on 28.257.5MHz quite strongly for about a minute before it faded away.

There have even been some contacts made and beacons heard on 6 metres, according to VHFDX.info. Let’s hope for some good openings on VHF this year.


Subscribe FREE to AmateurRadio.com's
Amateur Radio Newsletter

 
We never share your e-mail address.


Do you like to write?
Interesting project to share?
Helpful tips and ideas for other hams?

Submit an article and we will review it for publication on AmateurRadio.com!

Have a ham radio product or service?
Consider advertising on our site.

Are you a reporter covering ham radio?
Find ham radio experts for your story.

How to Set Up a Ham Radio Blog
Get started in less than 15 minutes!


  • Matt W1MST, Managing Editor




Sign up for our free
Amateur Radio Newsletter

Enter your e-mail address: