Hello Guy I agree that the 3x signal is caused by clipping. I had to really raise the signal up to get it to show up. If I set the noise baseline at -80 to -60 dB, the harmonic does not show up. It looks like if the signal peak goes higher than -20 dB on the MixW waterfall, the 3x starts to show up on DX Skimmer, but still is not seen on the MixW waterfall. I have to increase the signal even more to the point where the signal is just below 0 dB to see the 3x signal on the MixW waterfall.
I have tried with the AGC on and off, with about the same results re: where DX Skimmer shows it. The bottom line is keep your sound system adjusted so that the noise baseline is under -60 db, with AGC on, and you will not see these extra signals. The easiest way to adjust this is to use another program such as MixW in the spectrum display mode to see where the noise baseline is, and how strong the signal can get when AGC is on. I am seeing AGC kicking in when the strongest signal is about 30 dB above noise. 73, Clint KK7UQ Snip --------------------- 3 X the sound frequency sounds like sound card over-drive, or simply exceeding the actual linear range of the sound card. On-board sound chips and cheep Chinese sound cards are particularly vulnerable to showing odd-order effects if you look way down. Those can sometimes be significantly improved by managing the range of input sound and line-in levels. If you want to see a clean 100 dB range in audio devices, you will have to get a high-end audio card. The cheep stuff just doesn't go there. 73, Guy. ---------------------- -- View this message in context: http://elecraft.365791.n2.nabble.com/Multiple-Ghost-Image-CW-Decodes-While-Using-CW-Skimmer-a-K3-tp6070469p6074752.html Sent from the Elecraft 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
