[RFI] Low voltage lighting solid state "transformers"

Kelly Johnson n6kj.kelly at gmail.com
Sun Dec 17 18:12:19 EST 2006

The point is that it is NOT illegal to sell a device that meets the
emission standards.  It is only illegal to operate it in a way that
causes interference.  There's a big difference.  The burden is on the
USER to resolve the issue, not the manufacturer.  The FCC won't fine
the seller for the device, but could fine the user of the device.  In
my case, since I am the one that owned the device and it only
interfered with me then the FCC won't do anything to make the
manufacturer fix it.  If the device were owned by my neighbor, the FCC
could make the user stop using the device but they won't tell the
manufacturer to stop selling it since it meets the emission standards.
 Likewise, TV manufacturers are not required to fix TVI problems.  The
user gets the shaft.  That's the biggest problem with Part 15 rules:
the manufacturers have no responsibility to fix or replace equipment
unless is it violates emission standards.  That means that the typical
ham neighbor gets the shaft.  What is my neighbor supposed to do when
his TV picks up TVI from my LEGALLY OPERATING station?  Call the TV
manufacturer?  Yeah, right.  Name one television manufacturer that has
ever replaced or fixed a device that was experiencing TVI?

On 12/17/06, Tom Rauch <w8ji at contesting.com> wrote:
> > It may not violate FCC regulations.  I bought some LV
> > landscape lights
> > about 3 or 4 years ago along with a cheap power supply
> > made by
> > "Hampton Bay" for Home Depot.  This thing generated about
> > S7 or S8
> > noise on 20 meters from 100 feet away and wiped out the AM
> > BC radio in
> > my care from about 50 feet away or so.  It was hideous.  I
> > replaced it
> > with a Malibu transformer and all was well.  I sent the
> > power supply
> > to ARRL headquarters and they tested it.  The emissions
> > were not
> > strong enough to violate FCC regulations yet the noise was
> > very
> > strong.
> Technically any spurious emission that causes harmful
> interference to a licensed service is illegal regardless of
> absolute level.
> The ARRL also would have had to test the device in the
> actual working situation to be sure it fully complied.
> >The FCC radiation limits are not sufficient to prevent
> > interference even when the device is within limits.
> That's true for certain tests. That's why there is a blanket
> clause that says the licensed service can't suffer harmful
> interference. Of course we all know they won't generally
> enforce that type of rule, but I have seen them enforce it.
> I've seen them enforce it with broadcast stations that had
> harmonics that met spec but caused problems, and alarm
> systems that were incidental radiators.
> It is accurate to say the rules prohibit harmful
> interference, but the FCC is no longer run by people who
> understand communications systems. They are all political
> appointees based on who's buddy or son it is---and we keep
> re-electing the same crooked crew.
> 73 Tom

More information about the RFI mailing list