Low voltage lighting can often cause RFI due to it's control circuitry using
SCR's or TRAIC's. The control functions by conducting for a short variable
part of each 60 hz cycle resulting in a waveform rich in harmonics causing
hash well into the HF band.
The best solution is to install an EMI filter as it exit's the circuit. Take
a look on ebay where I've seen these emi filters for sale or do a search
with google to find manufacturers.
Another alternative would be to wrap the a/c input wiring to the circuit
board and also the exiting low voltage wiring with a few FT-140-43 toroids.
73,
Randy
WX5L
----- Original Message -----
From: "N6KJ" <kelly@thejohnsons.ws>
To: <rfi@contesting.com>
Sent: Friday, July 11, 2003 10:51 AM
Subject: [RFI] Low Voltage Walkway Light RFI
> Last night I tracked down one of the sources of RFI in my neighborhood.
> It turned out to be the low-voltage walkway lights I put in about 6 weeks
> ago. The lights are halogen lights manufactured by Malibu and the
> transformer(s) are made by Hampton Bay. Does anyone else have experience
> with this? Is this a problem with all of these lights or is it unique
> to this/these manufacturer(s)? Is this usually a transformer issue,
> a light issue, or a wiring issue? Is there anything I can do, except rip
them
> out or turn them off when I operate the rig? Are there any other walkway
> lights that I can get that are "quiet"? Maybe the solar ones?
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