RFI Problem Finally Solved

Rick

I've been battling a problem for far too long and this weekend I borrowed a friends heafty LiPo battery pack that was sufficient to power a non-Flex radio. This enabled me to throw all the breakers of in house and power them up one at a time. Once I identified the troublesome circuit, which fortunately was in my house despite the fact that the Hex Beam would null out the RFI, I could then start pulling plugs on individual components in the shack. I've attached a screen shot to show the severity of the problem on 20m. It turned out to be an older NEC computer monitor that was powered directly as opposed to the more typical outboard supplies we often see now. I've seen some similar posts on the list and thought I'd share my resolution. I'm clean as a whistle now!73
Rick, W2JAZ

EA4GLI

"throw all the breakers of in house and power them up one at a time." This is great advice, I always tell my colleagues to try this first. Glad you figured it out!

Kevin

Nice! I do the same every few months or so. I tend to gather a lot of gadgets and different things turn on as the seasons change. Over time it seems noise builds up slowly and I have the whack the sources. I'm kind of curious to see an after screenshot and, if at all possible, include the dB scale on the right?

Rick

I think I have another screen shot that does include the dB scale. If you really want it I can send it.

Kevin

I like to compare the numbers with what I see here at home. It just lets me know I'm in the ballpark with my setup (under-confidence). Just a curiosity.

Rick

ok Here you go. Different day but same old same old. I'll also attach a screen shot from after the problem was solved. Amazing!

Kevin

Huge difference!

My typical noise floor on 20 looks similar to your clean spectrum but signal strengths on my side are generally a few dB less than what you are seeing I think. I'm guessing living in a valley might account for that.

Thanks for the extra shots.

73,
Kev K4VD

Steve W6SDM

Great!  Nothing feels better than getting rid of RFI or a ground loop - except maybe a brother-in-law who's spent the last four years living in your basement.

Rick - W5FCX

Very nice. Thanks for sharing! It's about time for me to do the same.... last time I did I found a Chinese wall wart powering and old laptop that was killer... just have to find a time the XYL can be without power... maybe 4 am