In recent testing of a new Cloud-IQ SDR, I found the same thing at home. Two tones about 500 Hz apart and reoccurring at about the same interval. I used my KX3 to track it down to the 100BASE-T ethernet cables. The noise floor on the SDR is <140 dB and was able to pick it up.
73 Mike N4MHO On Mon, Jun 29, 2015 at 11:26 PM, Steve Lund <k6um.el...@gmail.com> wrote: > I have all these spurious signals in my K3, too. > > They are caused by my wireless router. But are the result of using wired > connections to my office computers. When I remove the LAN cables these > signals disappear, along with many on the hf bands. > > I have received the ferrites recommended by K9YC. The plan is to install > them on Wednesday. I have both the #43 and #61 material. > > Steve, K6UM > > On Mon, Jun 29, 2015 at 7:43 PM, Chris Hallinan <challi...@gmail.com> > wrote: > > > I've been playing around with 50 MHz USB/CW down at the low end of the > band > > with a plain ol' dipole. I'm curious about noise and birdies and other > > people's experience, as I really don't know what to expect. > > > > I have a steady S3/4 noise level at all frequencies with the preamp off, > > jumping to solid S5 with the preamp engaged. I have several strong > signals > > (probably harmonics of some interference??) as follows listening in USB > > mode, preamp off: > > > > 50.026: S4 > > 50.057: S6 > > 50.087: S5 > > 50.117: S6 > > 50.148: S6 > > 50:178: S4 > > and more as I tune up. Notice the 30KHz spacing. > > > > These are all steady 2-tone signals with perhaps a couple hundred hertz > > difference in the two tones. No variation with day/night or propagation > as > > far as I can tell. They all disappear when the antenna is disconnected. > > > > First, is my background noise level local or should that be expected on > 50 > > MHz? And what are these signals spaced every 30 KHz or so? > > > > Could this be broadcast overload way up here on 50 MHz? I do have a > fairly > > close 1580 KHz AM station broadcasting 1100 watts during daytime, and 110 > > at night, but I use an Array Solutions BCB filter. > > > > What have others experienced? > > > > Thanks and 73, > > > > Chris > > K1AY > > > > > > > > > > -- > > Life is like Linux - it never stands still. > > ______________________________________________________________ > > 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 > > Message delivered to k6um.el...@gmail.com > > > ______________________________________________________________ > 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 > Message delivered to m...@tropo.org > ______________________________________________________________ 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 Message delivered to arch...@mail-archive.com
