It appears that there are several sources for lines in the spectrum of the output on the LINE OUT jack. What I measured earlier today was at a LINE level of 015, at some value above that one can see that indeed the harmonics of the signal spectrum starts to appear -maybe due to some transformer effects as mentioned on the list, but at my settings and at this line out level this is not the case. Besides, I can measure something similar from the headphone output jack.
My original measurement with signal + unrelated line noise is here: http://www.qslnet.de/member/la3za/bilder/K3-CW-spectran.jpg Then I measured with the RF gain set to minimum, i.e. not signal: http://www.qslnet.de/member/la3za/bilder/K3-no-spectran.jpg But, I cannot say for sure that the K3 is the source of the line noise (1,2,3, ... kHz) as it appears even if I unplug the minijack cable (even with the K3 turned off), however at about 15 dB lower level: http://www.qslnet.de/member/la3za/bilder/K3-noConnect-spectran.jpg The only way to get rid of the lines is to unplug the cable at the PC-end: http://www.qslnet.de/member/la3za/bilder/K3-noCable-spectran.jpg So, for sure I cannot blame these lines on the K3 now, I need to understand better their source before making any conclusions. Sorry if I have made confusion on the list with these measurements. ----- Sverre, LA3ZA K2 #2198, K3 #3391 http://www.qslnet.de/member/la3za/K2/mod.html LA3ZA Unofficial Guide to K2 modifications -- View this message in context: http://n2.nabble.com/K3-Receiver-Noise-Level-Evaluation-and-Adjustment-tp4187070p4195440.html Sent from the [K3] mailing list archive at Nabble.com. ______________________________________________________________ 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
