[RFI] VLF interference Re: CFLs and LEDs

Roger (K8RI) k8ri at rogerhalstead.com
Sat Feb 7 18:39:16 EST 2009

Are we back on this topic AGAIN?<:-))

Dale Martin wrote:
>> I just had another interesting experience with a CFL.  I have a lamp in the
> den with a CFL.  It is on a mechanical timer to come on in the evening and
> go off after about 5 hours.  Last night my wife was sitting near the lamp
> when it came on.  She called to me saying the light is smoking.  The
> electronic ballast unit was hot and smoking.  Now, no harm done other than
> scratch one CFL, but what if no one had been home when this happened.
Probably nothing although I do emphasize the probably.  I've seen no 
reports of a CFL causing a fire.  I've had one smoke out of all we have 
installed. The base did get hot and it basically went fffffttttt!  The 
base was not as hot as the base on an incandescent during normal 
operation. We've replaced all the incandescents except floods on the 
front of the garage and shop.

>> This and their terribly short life are the reasons I hate CFL's.
With something on the order of  20 CFLs we've had the rare early failure 
and IIRC  there were only a couple early one and one since. (Neglecting 
the big on the the garage I filled with "Wasp and Hornet killer".) We 
have had a couple of failures in the garage, but both are mounted with 
in 2 to 3 feet of the garage door openers.
>> "Another fine mess you've gotten us into Ollie" Whoops my mistake It's our
> government and Al Gore that got us into this.
> Wow.  One lightbulb fries and suddenly it's 'the government's fault!!' Check
> under the bed, Martha! 
Think of it this way. Each CFL uses *about* 25% of the power the 
equivalent  incandescent for the same light output. However they are 
fluorescents which are pretty much monochrome and some people notice 
that as a decrease in light. IOW they don't see a 100 CFL putting out as 
much as a 100 watt incandescent. I happen to be one that notices the 
difference, or used to. Now at 25% it's been figured that if every home 
(based on the last census) changed just one 100 watter to a CFL that 
we'd save the power equivalent of quite a few power plants.  Our lights 
are on a lot as I'm up fairly late most nights, so I'd expect the amount 
saved over incandescents to be substantial.  But the lights are 
*usually* a small part of the electricity used in a home so I can 
understand not seeing a difference.   After all around here I can run a 
100 watt CFL for 24 hours at roughly 6.24 cents versus 24 cents for an 
incandescent. (we pay 10 cents per KWH) That'd be a really big 
difference in California where their rates are much higher.

I'm not a fan of Al, but he's got the right idea.
> Something caused the CFL ballast to fault.  I wonder if your 'mechanical
> timer' might not be the culprit.  Things mechanical do have a tendency to go
> awry more often than solid state suff.  
If his bill has not gone down and one or two bulbs used intermittently 
would be difficult to see out of the whole bill. Another thing is in an 
uncontrolled environment it's almost impossible to see the results from 
one minor change without logging all electrical use prior to and after 
the change for time and that means every device in the house.  An 
electric toaster, used a few times, the refrigerator door left open for 
just a couple of minutes (same stuff in there last time I looked), or 
even an extra minute in the shower if it's electricity heating the hot 
> I've got three CFL lights in the house on timers and never had a problem.
> I've got ten CFL lights in the house on regular light switches with no
> problems.  In the past three years or so, I have had one CFL fail.  Home
> Depot gave me a new one.  
> I like CFL's.  I like Al Gore.  
I like CFLs. No RFI and no real problems so far. We do have to remember 
too that the CFL is most likely going to remain an interim measure as we 
switch to LEDs which are already showing up.  As they are low voltage, 
DC devices they are likely to bring with them a whole new raft of RFI 
problems so we'd do well to monitor them closely by becoming early 
adopters (at least on a small scale) The vote is still out on Al, but we 
do need to be saving energy and changing the way we do things and here I 
am upgrading my computers to quad cores and state of the art video 
cards. I think you'll find the typical computer uses as much power as 
one of those 100 watt equivalent  CFLs per day even when it's turned 
off. On my big computer with the 850 watt PS turning off the PS is not 
enough, you have to unplug it.

I believe they call it compensation, or something similar but I figure I 
save enough power I can run that Alpha as much as I want as still come 
out ahead.  OTOH I normally run the Tokyo Hy-Power HL-1.5Kfx which is 
instant on with a KW PEP or CW out. I have to get serious to fire up the 
Alpha for an extra 50% which would be some where between 1 and 2 db.  
Driving my wife's hybrid most of the time saves far more  than enough 
for me to use my SUV (when needed) to haul things to large, too heavy, 
too *greasy*, and with sharp edges. Or to use it in 4WD to get through 
the snow banks.
Come to think of it, maybe I can build up those 4CX2500 amps and always 
be in tune.<:-))
> 73
> Dale, kg5u

Roger (K8RI)

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