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Old June 10th 05, 03:52 PM
SamSez
 
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"yea right" wrote in message
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On Thu, 09 Jun 2005 13:23:44 -0400, CycleOpps wrote:

Are there any solutions to eleminating or at least reducing the
interference caused by low voltage halogen lighting? Like many desk lamps
and accent lighting. My only solution so far is to make sure all lighting
in the house is off if I want to listen to the radio.


The problem is the dimmer in the halogen lamp. To verify, turn the light
all the way up in brightness and see if the interference goes away.


Yes and no. Dimmers were certainly the 'taditional' problem -- but there are
now a whole raft of new low voltage halogens that get their reduced voltage not
from a normal iron-core transformer, but from a cheap non-filtered switching
power supply [no dimmer involved at all]. These switching supplies have all
but replaced traditional transformers on the shelves of the chain stores. They
cause so much hash on the power lines that line-based remote control systems
[like X-10] won't even work if even one of these is turned on on that branch.
There are specific filter solutions for specific frequencies [again, like those
used by X-10], but they only block noise at the specific X-10 carrier frequency,
and do little for the rest of the band -- or for the direct radiated noise from
these plastic boxed 'jammers'. One wonders how these are even legal...

It would be cheaper to purchase a new light than to design and construct
a filter that would totally eliminate the cross-ovber harmonics from the
dimmer.


If the problem is from a switching supply, the only way to avoid the problem is
to either turn it off, or replace the supply with an iron core transformer
[while they are still available...]