[Elecraft] Noise sources

[Richard Fjeld]

I saw a post about finding sources of noise, and I would like to share one that surprised me.  The other night, I had 20/s9 noise on 75 meters all across the band.  I got out my portable AM radio and was trying to find the cause when I heard a click and the noise was gone.  I knew something had been turned off, so I went upstairs and asked my wife.  She had just turned off the 'puck' light that is under the kitchen cabinet. When I turned it back on, there was no doubt!

It is simply a 12V incandescent bulb.  Apparently the small metal box in-line on the power cord is a switching PS instead of a step-down transformer. 

Richard Fjeld, n0ce
rpfjeld at embarqmail.com
E=IR, it's the law.