His reports for my 1mW ERP have always been huge too. I was thinking there was some particular magic with the skip distance, but others in JN18/JN19 give me more modest S/N reports. 73s Roger G3XBM
Has F6CNI managed some sort of magic noise reduction system, or is it a just a case of being in a very quiet location... These are pretty impressive S/N values 2010-01-27 20:14 G4JNT 0.50387
G8HUH, monitoring WSPR... Your reports on Jim and myself seem to indicate an abnormally high S/N Are you in a very quiet location, or do you have a narrow CW filter selected? If the latter, WSPR
Andy Talbot pisze: Hindsight suggests we should all have normalised to 1Hz, quoting S/N in this width, but what's a constant 34dB offset amongst friends :-) Ok Andy yours, piotr, sq7mpj
At 391km this can't be realistic, and most likely comes from using a narrow filter - sub 200Hz - before feeding audio to the decoding software. The WSPR software does need a flat audio response
The WSPR software does its own digital filtering to the 200Hz wide input band - with associated passband edges, and calculations are based on the bandwidth defined there. It will therefore work,
Looking at the WSPR database, F6CNI is decoding me consistently in the 0dB S/N region. At 391km this can't be realistic, and most likely comes from using a narrow filter - sub 200Hz - before feed
Andy Talbot pisze: Looking at the WSPR database, F6CNI is decoding me consistently in the 0dB S/N region. At 391km this can't be realistic, and most likely comes from using a narrow filter - sub 200H
Some tests that were done a while back on this issue by several WSPR users, suggested, that the WSPR noise was measured in a bandwidth a little over the 200 Hz needed for the signalling- something li
Andy Talbot pisze: 300Hz wide CW filters made a fraction of a dB difference, compared with an SSB filter used as a reference; well, indeed , in my free time i have to look inside the wspr code .. i j
