Tuesday, May 17, 2011

WSPR Timing issues...

I left WSPR running overnight on 30 metres and when I checked it this morning, there seemed to be very few spots. The colour screen on top was showing several signals but I didn't seem to be decoding anything. I knew that timing is a big issue with WSPR so I checked the time on the PC and it seemed to be out maybe 2-3 seconds compared to the radio-controlled clock that I have in the shack.

I reset the time on the PC and hey presto, new spots appeared! So, I went checking...

These are some of my decodes before I reset the time. Notice the DT column...I had no idea what this was before but it stands for the 'Difference in Time' between you and the station you are hearing. As you can see above, most are roughly -2 seconds out.

As you can see above, when I checked early in the morning around 05:30 UTC, there were signals present but very few decodes except for F5GCD. Once I reset the time on the PC, loads of spots appeared and the 'DT' was less than 1 second.

I know that perhaps conditions improved around sunrise but to go from what looked like good signals in the colour window with no decodes to plenty of decodes after resetting the clock certainly suggests to me that timing was a factor.

It might also explain why sometimes I also see some signals on say 28 MHz but get no decodes.

As suggested in the WSPR forum, I downloaded Dimension4 and installed it.

For a PC running Windows 7, you have it run it as an administrator. Install Programme....In the Start Menu, right click on the programme logo...Select Compatibility...Under Privilege Level, tick the box 'Run this program as an administrator' ........click Apply....then OK

Run the programme and it should now keep your PC time updated.

Looking at the advice on the forum, they seem to suggest that signals need to be within 2-3 seconds. Hopefully, this will stop the problem.

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