[RFI] Torchere lamp

[EDWARDS, EDDIE J]

> -----Original Message-----
> From:	kboswell@aetn.org [SMTP:kboswell@aetn.org]
> Have a "torchiere" (sp?) lamp which uses a quartz halogen bulb and a
> dimmer control of some type. (Haven't opened the circuit yet).   Emits a
> raspy buzz which gets more noticeable on the higher HF bands.
> 
> Does anyone have suggestions on "curing" this noise-source?
> 
	[Ed-K0iL]  Howdy Kelly: 

	It's most likely the dimmer causing the problem.  An SCR or TRIAC is
used for variable control creating mucho harmonics and severe EMI in HF just
like the damnable touch controlled lamps!  If you are the owner, I'd get rid
of the lamp or take K0iW's advice (nice call George!) and replace the
controller or source of the noise with a simple ON/OFF switch.

	If ya want to try and keep it, try to find a controller that has EMI
filtering designed into it and replace the old one with it.  You may also
need to add a good AC-line filter and a common mode choke (15 turns of the
AC cord thru FT-240-61 ferrite core) placing it as close to the controller
as possible.  May need one on the input & output of the controller.  This
all will probably cost more than the lamp itself so see the first paragraph
for the cheap solutions!  

	I just resolved a touch lamp problem in my neighborhood that popped
up this summer.  Found it the first time out with a simple portable HF radio
from RS.  It was one I had found 7 years ago and I had quieted down enough
by simply unplugging an unused extension cord from their garage below the
room with the lamp (same AC circuit).

	Seems that they moved it to another circuit and, wallah, NOISE
again!  Took over a month to catch someone at home.  When I asked if they
still had the lamp and if they'd done something different with it, the guy
said yea, they moved it cause "they never use it anymore"!!!!  I asked if he
could just unplug so it wouldn't cause anymore interference, and he agreed.
Problem solved again...for now.

	Good luck Kelly!

	73,
	de ed K0iL
	Omaha, NE



--
Submissions:              rfi@contesting.com
Administrative requests:  rfi-REQUEST@contesting.com
WWW:                      http://www.contesting.com/rfi-faq.html
Questions:                owner-rfi@contesting.com