As noted in a previous post, I disconnected EVERYTHING. Nothing on the back panel of the K3 at all except for a Li-nano-phosphate battery as my power source. All AC off at the breaker panel for this room. The only electrical equipment on was my K3 via the battery and my Macbook Pro laptop via its battery.
Given those conditions, the hum was still there. Jim Brown suggested that I consider TXEQ to cut off the low frequencies, I did max cut for all frequencies up to 400 Hz. The hum did not start being attenuated until 400 Hz cut. But, max cut on 400 Hz did not attenuate it completely. I did not do higher frequencies. So, anyone who might help -- where does this hum or buzz come from if nothing is connected to the K3 and there is no AC flowing anywhere in the room. It is 28 degrees outside, which is freezing cold plus for the northwest and I am not used to that but my next step is to go outside and check my grounding to ground points. phil On Jan 13, 2012, at 10:03 AM, Geoffrey Mackenzie-Kennedy wrote: > When the KPA500 is in standby, I assume that its AC mains is still connected. > Have you tried pulling the KPA500's mains plug to narrow > the search? > > Is your P3 sitting between the KPA500 and the K3? > > 73, > Geoff > LX2AO > > On January 13, 2012, at 18:20 +0100, "Phil Hystad" <[email protected]> wrote: > > <snip> > >> If I lay my hand on the top of the K3 the hum disappears. If I lay my hand >> on the P3 sitting next to K3 the hum disappears but not as much. And, I can >> do the same with other grounded equipment. I have checked my grounds and >> they all seem to be pretty good. > > and earlier > >>> So, I am thinking maybe it has >>> something to do with the KPA500. So, I put that in Standby and the hum is >>> still there on the audio. The mic is the MH2 hand mic plugged into the >>> front of the K3. > ______________________________________________________________ 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
