[Elecraft] CFL lamp noise

[Jim Wiley]

Are you talking about a CFL, or a conventional fluorescent lamp? Many 
newer fluorescent lamps come with an electronic ballast.  These are 
sometimes a problem, in that the "ballast" operates like a switching 
power supply, and if not designed or built properly, can emit copious 
amounts of noise.   A standard "old fashioned" magnetic ballast does not 
have this problem.  If your lamp uses the newer electronic ballast, 
replacing the ballast with a magnetic type will fix the problem.


BTW, I have used many many CFLs and never had even the slightest bit of 
RFI from any current production units.  There was  a small amount of 
noise from some of the very early units of 20 years ago.  The last one 
of those I had was retired  circa 1995.  Most of the CFLs I have now are 
from Costco, and are FEIT brand, made in China.  Nary a peep from 
them.   We have about 35 CFLs in service now, and the 80-meter noise 
level is about S2 on a bad day,  closer to S1 normally.  (I live in a 
rural subdivision with underground power). 160 meter noise is about S3 
to S4,  and S0 for 40 meters and higher.


- Jim KL7CC


In my shack, where a fluorescent lamp is located only four feet from the 
rig, I recently switched from a 40 meter coax-fed dipole to a random 
wire with counterpoise directly into the K3, no coax. Lots of noise. 
Turn the switch off, noise goes away. Not a problem with coax-fed 
dipole. --Andrew, NV1B