Hello Jose,
I always set the sound card volume , the modulation, that when changing the volume setting , the output of the transmitter will follow in a linear fashion. This is very important in particuar for WSPR and WSPR-QSO modes. 73 Rein W6SZ --- In digitalradio@yahoogroups.com, "Jose A. Amador" <ama...@...> wrote: > > > No, and sorry if I misled anyone. I do have both WSJT and MultiPSK, I > nowadays use MultiPSK mostly for HF, but I have actually not come across > such a case > particularly with JT65. Of course it has been more than usual for some > particular ops on 14070, but in spite of the apparent simplicity, even > PSK31 is not plug and play stuff like a key and a CW transmitter used to > be in the past, it takes a bit of knowledge to get an SSB transceiver > with a clean soundcard mode signal on the air. > > 73, > > Jose, CO2JA > > PS: There is more I would like to do than the available free time allows > lately for me. > > --- > > El 06/03/2010 12:20, rein...@... escribió: > > Hello Jose, > > > > This was clearly a case of overloading, most likely on the transmitter > > side, over driving perhaps the sound card or the transmitter being > > over loaded by the sound card's signal. > > > > The K3 is too good a receiver, but it is part of your receiving chain. > > > > Properly running WSJT should not show it and as a full time WSJT > > operator, I have rarely seen it, recently at least, > > > > It is of course not my business, but I am surprised that you have no > > WSJT capabilities, it seems. > > > > 73 Rein W6SZ > > > > > > > > > > > > -----Original Message----- > > > >> From: "Jose A. Amador"<ama...@...> > >> Sent: Mar 6, 2010 8:54 AM > >> To: digitalradio@yahoogroups.com > >> Subject: Re: [digitalradio] JT65A harmonics > >> > >> El 06/03/2010 11:28, g4ilo escribió: > >> > >>> 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 > >>> > >>> > >> I have not seen that particular case. But the radio should be driven at > >> a reasonable lever where harmonics or unnaceptable IMD products are not > >> created. A SDR, becoming so common nowadays, cannot rely on the > >> filtering of hardware radios. > >> > >> Jose, CO2JA > >> > >> >
