I just replaced the 4ft LED noise makers in my kitchen that were made by Hyperikon. They were horrible generating S9 noise from about 10 MHz all the way to 144 MHz.
I replaced them with the Toggled brand that Home Depot sells. Model # D416-40321-2. FWIW, they have the FCC logo stamped on the box and light and mention the devices comply with FCC Part 15 Class B and Industry Canada license exempt standards.
So far, the lights are quiet as a mouse. Can't say the same for the 8ft LED tubes in the garage.
Some LEDS are good. The small simple non-dimmable ~60W equivalent
bulbs are the best because they do not have a switching power
supply. The circuit is basically a bridge rectifier with a capacitor
in series with the AC power to act as a current source. Absolutely
zero EMI. Pretty good for ~$1.00 each at Ace Hardware.
I have some inexpensive Braun 5000 lumen shop lights from Harbor
Freight in my lab that are quiet, which surprised me because other
HF items such as battery chargers have been terrible.
On 1/3/2025 12:49 PM, Renee K6FSB
wrote:
I had same/similar
issue extended up into HF and found a simple 20Amp Line filter
did the trick for me. I had found it in a surplus store ( like
in 2000) and had it for a rainy day....when I replaced the
fridge the issue started...old 1970 fridge = no issues , new
2005 fridge needed filter.
same thing for some of the led replacement florescent bulbs,
they may need rfi proof...some companies cheap out..there is a
place on their board but no parts....
Renée, K6FSB
On 1/3/25 9:13 AM, Brian Pease wrote:
Experimenting is in order. One thing you could try, with
care, is to plug in the fridge with a cheater adapter that
isolates the frame from ground to see if that helps. As a next
step, ground the frame to something other than the power line
3rd wire. Another thing would be an old school 60Hz isolation
transformer, although I have found there tends to be too much
capacitance between windings. A transformer with a groundable
shield between windings might work. You could try a UPS if you
had one large enough, but of course they can be their own source
of RFI. Then it is on to the line filter option.
On 1/3/2025 11:47 AM, Paul N1BUG
FN55mf wrote:
Since
my return I have been plagued by periodic RFI that reduces S/N
on
630m by 10 to 15 dB, maybe more at times. It tends to cycle on
for one
to three hours, then be off for a few to several hours.
Audibly in AM
mode it is a somewhat rough 120 Hz buzz. Noise blankers don't
touch it.
I can identify this RFI from below 10 kHz to above 500 kHz,
but there
are several broad peaks and valleys across the range. The
worst of them
is very broad centered approximately on 450 kHz but remaining
almost
flat up to and across 630m. I have not tried to find the upper
frequency
limit since I really don't care about anything above 500 kHz.
Early this morning I found it the culprit. It is my
refrigerator!
Perhaps a line filter will help, although my luck is rarely
that good.
I'm still chasing one, possibly two serious RFI sources
affecting 2200m
but won't go into that here.