Hi Oleg, One possible cause for the modulation you see could be a test tone harmonic generated by your PC, or by the K2's audio circuits.
If, for example, your PC is generating a 1000 Hz test tone *and* a 2000 Hz harmonic, then the output of the transmitter in SSB mode will be a carrier modulated by a 1000 Hz signal. The output carrier is the 1000 Hz tone translated up to RF, and the 1000 Hz "modulation" is caused by the 2000 Hz harmonic translated up to RF. Can you look at the output spectrum of your PC when it is generating a 1000 Hz test tone (disconnected from the K2) and measure the level of any harmonics relative to the level of the 1000 Hz tone? 73, Geoff GM4ESD dl0tuh wrote on Wednesday, March 10, 2010 at 12:00 AM: <snip> > I hope somebody can help me explaining the first oscillogram - where is this > AM > coming from? ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
