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...@electrica.cujae.edu.cu> >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 > > > >------------------------------------ > >Try Hamspots, PSKreporter, and K3UK Sked Page >http://www.obriensweb.com/skedpskr4.html >Suggesting calling frequencies: Modes <500Hz 3583,7073,14073,18103, >21073,24923, 28123 . Wider modes e.g. Olivia 32/1000, ROS16, ALE: 14109.7088. >Yahoo! Groups Links > > >
