Dave Holford wrote:

I recently purchased a pack of the small screw-in fluorescent bulbs and
the package contained a statement to the effect that although they had
been approved by the FCC they may cause interference to radios, wireless
networks, remote controllers etc.

A quick check with a portable HF receiver disclosed that they do indeed
radiate wide spectrum noise, although at a low enough level that I have
not noticed a problem when using an outdoor antenna with co-ax feed.

Some years ago there were rules concerning the use of dimmers near
radio telescopes because of the noise. All this stuff is accumulative.

How can any device that causes interference be type approved by UL
or the CSA? There may be some monetary incentives going on that we
aren't aware of.




mike