29 Apr 2015

Shack tidy-up: exhausted!

This afternoon I attempted to do, what in the past, would have been totally trivial: tidy up my shack a bit. After trying to sort just a couple of boxes I was totally exhausted. This is still an after-effect of my cerebellum brain bleed in September 2013.  Although, on the whole, I get less tired than I did, I still find that almost any burst of physical or mental activity leaves me exhausted.  I just have to relax, then I feel better. About 10-15 minutes and I am "done in". Oddly just walking or driving don't have the same effect. I have been able to walk about a mile OK for a year or more.

More aircraft reflections on 6m WSPR

M0YOU (116km) has been spotted again on 6m WSPR at a strong -9dB S/N. What is interesting is that all his recent signals have shown multiple reflections off planes (up to 5 at one time in the 2 minute TX window) but, so far, just one successful decode. Clearly these planes need to be flying in the right direction for a successful WSPR decode to take place. The reflected signals are strong but the WSPR TX burst is too long. A shorter TX burst would be better for this propagation mode.
M0YOU - catching reflections off planes in the Heathrow stack?
I suppose the Doppler would be less of an issue on 10m but far more of an issue on 2m. G3WKW (134km) and I managed to exchange 2-way WSPR on 2m last year, but it took a whole day to catch that right moment as I recall. Also as you go higher in frequency, rig drift becomes far more of an issue, so it can be more difficult again. For 70cms WSPR this becomes super-critical and an external reference frequency is all but essential so that you can know your frequency precisely.

G4FGJ (44km) has spotted me this afternoon but I think this was plain simple tropo as no Doppler was apparent. He was very strong with me at -2dB S/N.

6m WSPR

G3WKW (134km) was spotted yesterday on 6m WSPR.  I am pretty sure I can only get a path to Bob via aircraft reflections and I think it was aircraft approaching London Heathrow. Although I copied Bob's 5W I did not get spotted by him, although I am using a lower ERP and my signal was probably in the noise at his end, if indeed he was listening/looking.  Bob's 5W was around -24dB S/N with low Doppler. Of course, with aircraft, the WSPR software may not have decoded a stronger signal with more Doppler or more multi-path. It is not uncommon to see reflections from many aircraft in a single WSPR burst. Often decodes are impossible unless aircraft flight patterns result in low Doppler.

In this regard, WSPR may not be the best mode. Also WSPR TX bursts are nearly 2 minutes long and this is a long time with passing planes. Other digital modes with shorter TX bursts are probably better. In this regard, passing planes are more like MS bursts so modes well suited to MS would be better.

Sunspots and 10m - Wed April 29th 2015

Sunspot number has fallen yet again to just 36 (K=0) and 10m daytime propagation is expected to be "poor".  With quiet conditions, I am not ruling out a late, short USA 10m opening. Yesterday 10m did open to the USA but only a single station spotted my 500mW 10m WSPR beacon and that was late in the evening.

UPDATE 1038z:   On 10m WSPR EA8BVP (2986km) was spotting me early again and IZ6QZB (1475km) has spotted me once.  I think this is a mix of single hop F2 (EA8) and Es (IZ6).

28 Apr 2015

USA on 10m WSPR after all

Well I'll be damned! AC2EG (5610km) has spotted me several times on 10m WSPR in the last half an hour.   So, despite my dire expectations, 10m WSPR has opened to the USA for the fourth day running! This despite forecasts for 10m being "poor" today. Amazing.

6m WSPR - spots by G3ZJO

So far this afternoon, G3ZJO (79km) has spotted me lots of times on 6m WSPR this afternoon. No great DX but this looks like pure tropo. So far, I have not seen any Es on 6m.

No USA (yet) on 10m but some good N-S DX

As yet (1525z) no sign of spots from the USA but FR1GZ (9724km) has spotted my 500mW 10m WSPR several times this afternoon. If this is another "poor" day, then I am happy.

UPDATE 1934z:  Still no sign of any USA 10m WSPR spots of my 500mW WSPR beacon today. Plenty of spots from EA8BVP and FR1GZ but absolutely nothing from the USA. I think we were lucky having propagation across the North Atlantic for the last 3 days. I guess the band could still open to the USA but  this is pretty unlikely now.

EA8BVP early

EA8BVP (2986km) has already spotted my 10m WSPR many times starting at 0640z. This is very early.

UPDATE 1527z:  As yet, no USA spots but FR1GZ has spotted me several times.

Sunspots and 10m - April 28th 2015

Sunspot number has fallen again to 42 (K=1) and the forecast for 10m is "poor".

27 Apr 2015

At last - a 6m WSPR spot!

The last few days have been very quiet on 6m, but this evening, at last, I was spotted by a relatively local station M0MVB (30km) at a decent -10dB S/N.   Still no Es reports on 6m as yet.

UPDATE 1842z:  3 further reports received from M0MVB. All suggest some influence from aircraft reflections as there was Doppler shift on all reports or it could be M0MVB's rig drift? On one spot (later than those shown) the drift was 4Hz, which definitely looks like a plane.
6m WSPR spots this evening from M0MVB