Hi Adam, As Wayne pointed out, and as I suspected, I was kind of beating a dead horse due to the noise level I have. I have done something similar to what you did--turning off various circuits in the house to see if much of the noise disappeared. It didn't seem to make much difference here, but I need to check this out more effectively.
I suspect some of my problem could be due to using a vertical antenna, which tends to pick up noise more easily than a horizontal antenna might. I hope to try some comparative testing using some sort of dipole to see if things improve. Power lines are always a suspect! I have some too that aren't all that far away. Our neighborhood had underground utilities, but I live near the periphery, and there are poles that run along the edge of the development. I'll be doing some RF sniffing around there! Your noise level does seem quite high, so I feel certain you will find some culprits if you can do some additional checking around your location. You might want to give your local power company a call as well, if you suspect any of your noise is coming from those poles. Dave W7AQK ----- Original Message ----- From: "Adam Koczarski" <ka7...@ka7ark.com> To: <elecraft@mailman.qth.net> Sent: Monday, January 12, 2009 8:47 AM Subject: Re: [Elecraft] Using K3's Pre-amp > >> -----Original Message----- >> From: elecraft-boun...@mailman.qth.net [mailto:elecraft- >> boun...@mailman.qth.net] On Behalf Of wayne burdick >> Sent: Friday, January 09, 2009 8:53 PM >> To: Dave Yarnes >> Cc: elecraft@mailman.qth.net >> Subject: Re: [Elecraft] Using K3's Pre-amp >> >> The noise floor is your entire problem :) It's a fact that the preamp >> improves the MDS of the K3 by at least several dB. But if your noise >> floor is S4, it will do not good at all, because all lower signals are >> already masked by the noise. > > I just ran a noise experiment at my QTH yesterday. My typical noise is > s7.0 > S6.5 s7.5 on 80m, 40m & 20m respectively. With every circuit in the house > off, except the one the radio is on, and with only the power supply and > the > radio on that one circuit the noise is s4.0 S4.75 s5.0. I turned on > circuits > one at a time and recorded to S level jump for each. The 'home > entertainment > center' seems to be the biggest contributor so I'll start there. Now I > just > need to figure out how the switch off the neighborhood transformers and > silence my neighbors! :) > > I have some fairly large power lines across the street. Are they usually > strong contributors to noise? > > You can see the resulting data here: > http://www.ka7ark.com/20080111QTHnoise/pics.html > > > Adam - ka7ark > > > _______________________________________________ > Elecraft mailing list > Post to: Elecraft@mailman.qth.net > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
