While doing some tests tonight to compare the white noise of my Icom IC-7000 to the white noise of the KX3, both having the AF gain turned all the way down, I noticed something a little unusual in the KX3's spectrum:
http://imgur.com/0QF9vXh There is quite a spike of noise at 12kHz (well, relative to everything else around it anyway), with harmonics at 24, 36, and 48 kHz. The latter three of course are inaudible to humans. I found that even without the considerable amplification that I was using to get the levels high enough to analyze, I was able to hear the 12kHz tone in my headphones with the AF gain turned up higher than 30 or so. The sound is present even with everything else disconnected from the unit, and it begins immediately after it is powered up, before it begins receiving. I could see it possibly giving someone fatigue or a headache after a while, even if not consciously aware of it. Has anyone else experienced this, or does anyone have the test equipment to see whether this is present for others and not just me? Nick -- *N6OL* Saying something doesn't make it true. Belief in something doesn't make it real. And if you have to lie to support a position, that position is not worth supporting. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
