In WSPR it sometimes happens that stations are spotted +50Hz and -50Hz their dial frequency.
--- In [email protected], Andy obrien <k3uka...@...> wrote: > > While harmonics from modes like PSK31 are common, I have never seen a JT65A > signal generate what you describe. Interesting. > Andy K3UK > > On Sat, Mar 6, 2010 at 11:28 AM, g4ilo <jul...@...> wrote: > > > > > > > I was listening down around 14.077, just above some slow FSK mode which I > > think is JT65A. The JT65A was tuned quite low pitched in my receiver, and I > > could clearly see "images" of it over to the right. Judging by the spacing > > of the "image" tones I was seeing an audio third harmonic of the original > > signal. The image tones were clearly visible and would have been copyiable > > in their own right if not for the 3x spacing. > > > > My transceiver is a K3 and the signal was just an S9 so overload or > > intermod are unlikely to be the issue, but to make sure the images weren't > > being generated this end I tuned in some strong RTTY and found no harmonic > > images of the signal. > > > > Has anyone else seen this? Aren't the tones supposed to be generated at > > such a frequency that any harmonics are cut off by the SSB filter? > > > > Julian, G4ILO > > > > > > >
