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WSPR extension needs more precision for accurate reporting with VHF&UHF converters

I've been testing my 0-2 GHz transverter out lately and in the process have tried to use the on-board Kiwi WSPR extension. It works fine since the Kiwi is really only an IF for the downconverter portion of the TRansverter, decodes are OK. However, the frequency reported to is not correct. By 23cm it is off at least 122 Hz in one instance.

Meanwhile using the same Kiwi with WD everything is completely correct and reported frequency is accurate to the last Hz at 1296.500000 MHz dial setting. Looking at the waterfall on the Kiwi everything looks just fine as well. There's no error of the size reported by either WD or the waterfall.

I think what has happened is that in adding the frequency offset option to the Kiwi that there is no longer enough numerical precision. So even though the Kiwi rx is working fine, the extension can't accurately represent the frequency.

I don't think this is a high-priority issue, probably not that many users are using the WSPR extension at VHF or UHF with an accurate and stable downconverter yet but if improvements or changes are made to the WSPR extension sometime in the future, it would be good to increase the library precision so that it can accurately report frequencis.

Glenn n6gn


  • Thanks Glenn. I have it on my list now. Almost certainly a float that needs to be changed to a double.

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