29 Oct 2014

30m WSPR transceiver kit

By now, you probably realise that I just love WSPR. With quite simple equipment it is possible to be decoded across the planet consistently with real QRP power levels.   I am always on the look-out for new ideas, although until my health improves I am not in a position to build too much myself. See http://www.knology.net/~gmarcus/WSPR/wspr_v4.pdf for an example of a complete 30m WSPR transceiver.

This is NOT a new circuit  - it has been around for some years - and it still needs a PC for the WSPR software. Some TX-only WSPR beacons use microprocessors to generate the WSPR TX messages, thereby freeing up the PC and consuming little power overall. Some sync to GPS to avoid timing issues too.

QSYed to 472kHz WSPR

For some reason the WSPR4 software stopped working late this afternoon. I decided to restart it but on 472kHz with 5mW ERP instead of with 500mW on 28.1246MHz. As yet, I am being spotted by the 472kHz WSPR stations that have already spotted me before and I am seeing stations I have spotted before.  Now I have my shack back I shall leave the 472kHz WSPR running overnight.

UPDATE 1852z:   Best DX so far this evening, on 472kHz WSPR RX, is F1AFJ (607km).  I expect this will be exceeded later.

UPDATE 1940z:   Best DX on 472kHz WSPR RX this evening so far is now DH5RAE (995km). My 5mW ERP on MF has reached PA3ABK/2 (306km) this evening.

UPDATE 1945z:  A single TX burst on 472kHz WSPR with just 5mW ERP  gets me typically 2 to 4 spots per transmission, which is not too bad I reckon.

UPDATE 2000z: I should really try a bit on 137kHz WSPR from this QTH.  This QTH is quiet and I should be able to hear WSPR from the nearer Europeans and there is an outside chance of being copied by a few semi-locals. I really need a longer baseline earth-electrode system though and the 137kHz transverter needs a rebuild and my health is not really up to these tasks.

UPDATE 2100z:  LA3EQ (769km) running 2mW ERP has been spotted 3 times so far this evening on 472kHz WSPR.

10m results with 500mW out

Just 500mW seems quite enough to get plenty of 10m WSPR spots. The table below shows just recent spots. The actual power from the antenna is probably 1-2dB less than 500mW because of cable losses.
Recent 10m WSPR spots running 500mW from rig.
UPDATE 1520z: So far today on 10m, with 500mW, I have received 174 reports and the day is far from over.

USA copying my 500mW 10m WSPR before lunch

WG2Z (5600km) was the first USA station to copy my QRP 10m WSPR signal at 1152z this morning. 500mW is again quite enough to span the Atlantic Ocean on 10m WSPR. Today looks like being another good day on the 10m band.

I may try JT65 or JT9-1 for some 2-way QSOs on 10m.

Sunspots and 10m conditions

Sunspot number has drifted down to 138 (still good) and daytime 10m conditions are forecast to be "fair".

I am using 500mW WSPR on 10m and am having no problems getting plenty of spots. Best DX so far this morning is 4X1RF (3519km) who gave my -12dB S/N.  I expect the band to open to the USA shortly.

UPDATE 1052z: Best 10m WSPR DX on RX here (so far) is HS0ZKM (9485km).

28 Oct 2014

QRT for the night

At 1822z I had to go QRT as my shack is being used as a nursery. Normal service will be resumed tomorrow. I finished on 10m with 500mW. Normally, I QSY down to 630m around this time. Slowly but surely the number of stations spotting me is increasing on 630m (472kHz) WSPR. I have still to calculate the all-time 472kHz WSPR spots from this QTH. Best DX report is just over 1000km (LA4ANA) with 5mW ERP. On RX the best DX is EA and I. At the moment I am lucky that this QTH is electrically quiet on RX on 472kHz WSPR.  It is actually better than the old QTH. Of course, this could change overnight.

500mW on 10m

A few minutes ago I turned the WSPR power back to 500mW, 5 spots from the first transmission with 3 of the 5 being spots from the USA and Canada. Yet again, 500mW seems quite enough on 10m. Very few extra stations spot me with higher power: just better reports on the whole with 2W.


Sunspot number today is a respectable 138 but daytime 10m conditions are described as just "fair". Nonetheless, 10m is again wide open with very strong 10m WSPR signals from the USA. Right now conditions on 10m are very nice. In previous sunspot cycle peaks we may have seen 6m F2 propagation but with the current state of play, this is unlikely.

27 Oct 2014


For GDX on 6m at this time of year I think more than 1W ERP is needed. The cable loss to my V2000 vertical is at least 1dB as I use a run of RG58 coax. I was quite surprised just how few UK stations were active on the 6m band. Back in the summer months when Es was plentiful I used to copy and be copied by, GDX stations by tropo or plane reflection out to around 200km most days. It seems outside the Es season the band gets largely vacated at this time of year, on WSPR at least. The couple of active UK stations were not copied here and did not copy me. As Doppler from moving planes is a big problem on VHF WSPR, it can take all day to get a favourable reflection that actualy decodes.

So, I am giving up on 6m for now. Life is too short and I lack the patience. I could run 5W from my FT817 but don't want to risk blowing the PAs at full power for nearly 2 minutes.

Not on tonight

As my shack is being used as a nursery for a couple of nights, evening MF operation is out of the question. Normal evening operation will resume on Wednesday.

For now, I am giving up on 6m. After 4 days and not a single spot given or received, can you blame me? Day time I shall concentrate on 10m and in the evenings I'll QSY down to MF, 630m (472kHz) WSPR.