I think the "divide and conquer" approach is the best. Hopefully the source(s)
are in your own home, much easier
to resolve. What I did was to connect a 12 volt battery to my K3 so I could
listen without needing AC. Then shut off the main
breaker to the house. The noise was gone (yay!) Then one at a time turned on
each individual breaker until the noise started again.
Then went around and unplugged everything one at a time on that circuit until
the noise went away. I discovered I had two circuits with
noise offenders. One was a Mikita battery charger for a battery powered drill
in the garage. The second was a DirecTV receiver. It was the worst.
Even though it was turned off it radiated noise because the power supply is on
all the time. ( So it is best to unplug everything when testing !) I called
and they acknowledged that some of the receivers can have RFI issues. They
sent me a new receiver in a few days and no more problem.
I have tried doing sleuthing with a portable AM radio but it wasn't effective
at all, the AC lines conduct and radiate the noise so it is hard to nail down.
Hopes this helps and hope it is in your own home !
On Dec 22, 2011, at 8:03 PM, D Rodman MD wrote:
> Here is my situation. I am pretty sure noise is from switching power
> Unfortunately, it tends to put noise right where I don't want it. Like
> bottom of
> 160, 80 and 40m. Typically the noise is 20-25 kHz of S8-9. One hears
> modulations on it and the whole band moves up and down in frequency 15-25 kHz
> over many hours. Best way to locate, inside house, outside house and
> David J Rodman, MD
> Assistant Clinical Professor
> Department of Ophthalmology
> Office 716-857-8654
> UR RST IS ... ... ..9 QSB QSB - hw? BK
UR RST IS ... ... ..9 QSB QSB - hw? BK