In message <[email protected]>, dated Wed, 4 Jun 2014, Richard
Nute <[email protected]> writes:
"Class B limits are amazingly conservative, to which large populations
of devices ascribe."
Try using an ordinary AM radio beside a compact fluorescent lamp
as on a beside table.
IS a CFL a 'digital device'?
Yes, well, this is the elephant in the room of radiated emissions. It's
called 'separation distance', which is a bit tautological. Measurements
made with very low separation are generally not reproducible, which for
regulatory purposes is much more important that being realistic.
So standards call for measurements at (mostly) 3 m and 10 m, where
reproducibility is (if one is very careful) adequate. At 10 cm, you
don't get results, you get options. (;-)
--
OOO - Own Opinions Only. With best wishes. See www.jmwa.demon.co.uk
Quid faciamus nisi sit?
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK
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