8 Aug 2014

472kHz WSPR so far today

472kHz WSPR unique reports so far this summer (duplicates NOT shown)
So far this summer, a reasonable number of WSPR spots, but an absence of WSPR spots of me from stations outside the UK.

G8ALS on 472kHz WSPR

G8ALS (126km) is consistently receiving me on 472kHz WSPR in daylight. My QRPp signals seem to be a few dB over the noise threshold but he is copying me, which is good. I am still using the end-fed PAR wire antenna with feeders strapped via a 3C90 matching coil and a 110mm diameter indoor loading coil.

Storms to (just) miss us today?

See http://www.lightningmaps.org/realtime?lang=en .   For now, the local thunder and lightning appears to be just avoiding us: it has tracked from Cambridge up into the Fens and seems to be moving NE. This is good news.
http://www.lightningmaps.org/realtime?lang=en
UPDATE 1600z:  There are new storms to the south of Newmarket and we can hear thunder in the distance now.  At the moment these are moving NE as well but I shall disconnect rigs, antennas and PC if they get too close.

UPDATE 1606z:  Lightning now just east of Newmarket and getting closer! Decision on going QRT will be taken in next few minutes.

G3WCB on 472kHz

G3WCB (101km) and I are currently exchanging daytime spots on 472kHz WSPR. He is just copying me (on the noise floor) and he is generally about 10dB stronger than I am. I suspect his antenna on TX is considerably better than mine.

Sunspots

The current sunspot count is 158 (good) and 20-30MHz conditions are "normal",  so I'd expect some decent N-S F2 propagation on 10m today. At the moment, I am sticking with MF (472kHz) , but may revert to 10m over the weekend, weather permitting.

We have thunder and lightning possible as the remnants of Hurricane Bertha pass through over the weekend. See http://www.lightningmaps.org/realtime?lang=en .  Currently, the storms are just missing us here in Burwell.

472kHz antennas and results overnight

The Par antenna (strapped feeders) seems to be somewhat better than the 2m/70cm feeder as an antenna on 472kHz.  I have now received 472kHz WSPR spots from 8 unique stations so far.  The Par seems to be directional as reports from GM4SLV (although plentiful overnight) seem no stronger.
Unique 472kHz WSPR spots so far
Tonight,  I shall load up the feeders to my V2000 6/2/70cm vertical and 2m halo on 472kHz as these are my highest antennas and compare results with previous antennas. Best 472kHz DX spot this summer is still from GM4SLV (896km) up in the Shetland Is.. I suspect the Par will be the best antenna though. Really I should make a dedicated 472kHz vertical but my health does not allow me to do this currently, so compromise antennas are the order of the day!

UPDATE 1102z:   GM4SLV was spotting me at 0948z this morning. This daylight!

UPDATE 1107z:  I am very surprised not to have been spotted outside the British Isles so far on 472kHz.  I have copied PA, DL and F so far here as well as UK stations.

7 Aug 2014

M0EMM - 3-6dB stronger reports on 472kHz with Par antenna (strapped feeders)

M0EMM is spotting me on 472kHz WSPR some 3-6dB better than last night because of the change in antenna. I need to recalculate the actual ERP,  but believe it is still in the low milliwatt region.  I shall leave 472kHz WSPR running overnight so I can see who else is getting my signal and at what strength.

6m - little missed. 630m more of a challenge now.

Since QSYing down to 630m MF, I was wondering what I'd been missing on 6m. A quick check on WSPRnet.org suggests only EU Es out to about 2000km, so I am not missing too much. My biggest concern is the moment I abandon the 6m band there will be a collosal transatlantic opening!

At the moment, 630m with real QRP is much more of a challenge.

UPDATE 1920z:   Now 7 unique stations have spotted me on 630m so far this summer.  Plenty more likely.
Unique 630m WSPR spots of my signal so far

472kHz - getting decent results with Par antenna

472kHz WSPR spots of my QRPp signal so far
Results with the end fed Par 10/20/40m antenna (with strapped feeder) are better than with the feeder to the 2m/70cm yagi. Today M0PPP (182km) and G3WCB (101km) have spotted me in the daytime for the first time this season. I came back to the 472kHz band yesterday.

472kHz - improvements?

Using the strapped feeder to my Par 10/20/40m as my 472kHz antenna rather than my 2m/70cm feeder, the antenna current has nearly doubled with the antenna current meter now showing 30-33uA whereas it was 18uA before. This suggests ERP has increased by around 4-5dB (ERP proportional to I^^2), but we'll see later. The Par antenna itself is lower than the 2m/70cm antenna and runs horizontally to a tree. Average height is around 3-4m AGL. The losses may be greater.

The picture shows the 472kHz coil used (a ferrite rod would be fine but since moving it is "lost"), the 472kHz homebrew transverter (left) and the 3C90 matching coil between transverter and antenna (towards centre, LHS of coil). The small meter measures antenna current and registered 18uA last night and 30-33uA now with the Par antenna with strapped feeders.

UPDATE 1420z: G8HUH (250km) is copying in daylight a full 8dB S/N better than last night. Encouraging.

UPDATE 1448z:  M0PPP (182km) seems to be coming in stronger than last night too and in broad daylight.

UPDATE 1700z:  M0PPP  is now spotting me at 1456z, 1538z and 1620z i.e. in daylight.   He was not copying me at all last night, so I think my signal IS stronger.