[RFI] Noise changes when room lights turn on / off

[Tony]

All:

Thanks for all the great advice. A local offered to stop by and lend me 
his battery powered FT-817 to sniff out the noise. The plan is cut the 
power and turn on each breaker one by one. That should isolate the 
source of the noise and the rig should help find it. The odd thing about 
the noise is that it only comes on in the evening. I monitored the HF 
rig over several days, throughout the day and it was very quite. There 
must be something in the house that's on a timer that I'm unaware of.

As I mentioned yesterday, the noise changes when I turn the shack light 
on and off (see post with video below) which would indicate that there's 
something going on with the house wiring or possibly some device.

I seem to remember hearing about an RFI case where the noise was coming 
in from the power lines onto the AC in the house. Has anyone experience 
this sort of thing?

Thank you all.

I'll report back as soon as I get the portable rig.

Tony -K2MO




> All:
>
> The noise that appeared this evening at 7:00pm may have something to 
> do with AC power coming into the house. I noticed that the noise 
> changed when I turned the shack light on and off. This video shows 
> what happens: http://www.youtube.com/watch?v=EYHbpLfQ1gc
>
> There are no florescent lights or touch lamps in the house. Unplugging 
> the shack light does not make the noise go away. Turning the shack's 
> light switch on or off with the light unplugged does not change the 
> noise. The noise persists with power supplies, computers and TV's 
> turned off or unplugged.
>
> I'll investigate further and report back tomorrow.
>
> Thanks,
>
> Tony -K2MO