For several years there have been annoying carriers on the SW bands at my
location - one of which was parked on top of WWV 10MHz. I recently decided
to track down some various RFI noise and discovered that my home intercom
system was the culprit. The one I have includes an AM/FM receiver and I
think it's the FM section putting out a carrier on or about 10MHz.

Hope this helps someone with similar troubles.