LED lighting RF interference?

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Silent Key
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I keep hearing people claiming that LED light bulbs are causing RF interference. Does anyone know what frequencies they are affecting?
 

ipfd320

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Its not just led lighting--there are smart meters / solar panels / computer power supplies / wall warts / refridgerators / washers / Stuff back feeding thru the electric grid from a neighbors house and alot more

as for the led lighting--it can happen on 1 frequency and or many combined up and down the spectrum--its not the lights that does this its the led drivers that make this mess--I Have also seen and replaced light dimmer switches with the neon night light in it causing backfed interference thru the house wiring

with all the cheap energy saver electronics being produced its hard to track down sources causing this interference--you will get a million answers and observations on this question so be Prepared
 

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Its not just led lighting--there are smart meters / solar panels / computer power supplies / wall warts / refridgerators / washers / Stuff back feeding thru the electric grid from a neighbors house and alot more

as for the led lighting--it can happen on 1 frequency and or many combined up and down the spectrum--its not the lights that does this its the led drivers that make this mess--I Have also seen and replaced light dimmer switches with the neon night light in it causing backfed interference thru the house wiring

with all the cheap energy saver electronics being produced its hard to track down sources causing this interference--you will get a million answers and observations on this question so be Prepared


I'm familiar with most of these. I've been playing in the radio hobby since my first CB back in the 60's. I'm deep into computers and other gadgets of all types. Most of the potential for problems are at higher than HF bands, and I've been especially lucky in avoiding them in most cases. I was especially curious about the LED bulbs.
 

prcguy

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I see lots of interference from household 120V LED lights mostly in the VHF through UHF range, especially from CREE and other brands sold at Lowes and Home Depot. The interference is so bad it can wipe out all reception of strong repeaters in the 2m band on a hand held radio when in the same room as the LED lights.
I also have some small profile ceiling track lighting where I replaced the snap in power supply/fixture with newer LED types and those wipe out everything from HF through UHF.

I was able to reduce the interference to an almost acceptable level in my screw in sockets by placing three #43 mix snap on ferrite beads on the AC power wiring right at the light socket. I need to do some further testing but my goal is to use one ferrite bead with two turns of wire through it which should be as effective as 3 or 4 beads with a single run through them. The key here is how much wire slack do you have in the ceiling or wall to get enough wire to clamp the bead around. I have not been able to address the problem with track lighting yet.


I keep hearing people claiming that LED light bulbs are causing RF interference. Does anyone know what frequencies they are affecting?
 

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Silent Key
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I see lots of interference from household 120V LED lights mostly in the VHF through UHF range, especially from CREE and other brands sold at Lowes and Home Depot. The interference is so bad it can wipe out all reception of strong repeaters in the 2m band on a hand held radio when in the same room as the LED lights.
I also have some small profile ceiling track lighting where I replaced the snap in power supply/fixture with newer LED types and those wipe out everything from HF through UHF.

I was able to reduce the interference to an almost acceptable level in my screw in sockets by placing three #43 mix snap on ferrite beads on the AC power wiring right at the light socket. I need to do some further testing but my goal is to use one ferrite bead with two turns of wire through it which should be as effective as 3 or 4 beads with a single run through them. The key here is how much wire slack do you have in the ceiling or wall to get enough wire to clamp the bead around. I have not been able to address the problem with track lighting yet.

I replaced all the light bulbs in my entire home with CREE 60W (equivalent) LEDs about four years ago. To make matters worse my office/radio room has LED track lighting with four Phillips 50W (equivalent) flood lights. As horrible that sounds, I haven't noticed a particular problem with them for the things I monitor, mostly 850MHz band and VHF/UHF aircraft bands. However I recently picked up an HF transceiver with the intention to do some monitor of the HF bands. All my VHF/UHF antennas are actually indoors, and worse yet, in my office! But again no serious problems I'm aware of. HF will be another story for sure.

Having just had my second open heart surgery in five years, five weeks ago, I won't be able to do anything outside or on a ladder until spring. Michigan's winter is coming soon!
 

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Silent Key
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I see lots of interference from household 120V LED lights mostly in the VHF through UHF range, especially from CREE and other brands sold at Lowes and Home Depot. The interference is so bad it can wipe out all reception of strong repeaters in the 2m band on a hand held radio when in the same room as the LED lights.


So the RF interference from the CREE brand is wide band, not just one particular frequency? I'm surprised this didn't cause a class action lawsuit.
 

a29zuk

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I don't use the Cree model lights. The small individual bulbs do not give me a problem. They will emit noise only a few feet away. If I use a battery operated receiver and move it close to the lamp I will get interference(buzzing sound)throughout the MW and HF spectrum. Everything on outside antennas are not affected.

The four foot LED light fixtures in my laundry room and garage are more powerful and will generate noise farther. On some frequencies I have to shut them off and use an alternative light source when monitoring MW/HF. These also affect my police scanners in the VHF-Hi range but do not seem to have any effect on 800mhz.

Jim
 
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dlwtrunked

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So the RF interference from the CREE brand is wide band, not just one particular frequency? I'm surprised this didn't cause a class action lawsuit.

When LED bulbs first were coming out, I wrote an article where I carefully measured the interference produced by them and submitted it to the ARRL for possible publication in QST. The ARRL's response was a short letter with 3 points:

1. We will not publish your article.
2. Do not submit it to any of our other publications.
3. We will not explain why. (Yes, they actually said that.)

I have acted as an editor for technical publications. One never responds in that way unless something crooked is going on or one is both lazy and stupid. I later showed this to a retiring ARRL president. His response was basically WTF.

You can blame the interference on the ARRL. You do not need to look further.
(They have had some minor too late comments about the interference much later.)
 

bchappuie

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I know if I put LED bulbs in my Garage Door opener, i have to be like 10 ft or less in front of the door for the remote to open the door.
 

Boombox

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I have one LED light (cheap brand) about eight feet from my Sangean PR-D5 and another one (cheap brand) maybe 12 feet from it. No interference in either MW or FM. Both lights are on 24/7 -- I get no interference in other areas of the house. My router puts out more RFI.

I have another radio (an AM-FM boombox) that got RFI from an LED bulb that was possibly a different brand. I think a lot of it depends on the brand, and maybe the type of lighting fixture (one with a long metal arm might act as an RFI antenna). As to what frequencies can be affected, I can't say. I haven't noticed any RFI on SW aside from what I get off my router. Not sure if this helps at all, but it is my experience with it.
 

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The LEDs I have on the most are all in metal cans, either recessed, or track lighting with can type fixtures. I wonder if that helps to shield the interference. But all those bulbs are Phillips, not CREE.
 

12dbsinad

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I have found Lowes and Home Depot screw in LED's (standard base) to be terrible with RFI. The best ones so far for cheap are the wal mart great value brand believe it or not. They emit damn near nothing.

And people wonder why their radios and other wireless devices don't work... walk in with a spectrum analyzer and it looks like a forest.
 

prcguy

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The can's don't shield much as the wiring in the ceiling becomes an antenna and radiates the mess. The power supplies for my track lighting are in little rectangular plastic boxes with no shielding. Its actually the switching power supply in an LED light that makes the RFI and really nothing to do with the LED itself.

The LEDs I have on the most are all in metal cans, either recessed, or track lighting with can type fixtures. I wonder if that helps to shield the interference. But all those bulbs are Phillips, not CREE.
 

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Silent Key
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The power supplies for my track lighting are in little rectangular plastic boxes with no shielding. Its actually the switching power supply in an LED light that makes the RFI and really nothing to do with the LED itself.

My track is 120VAC with Phillips LED floods screwed in the 120V sockets.
On future purchases I'll be looking for this symbol on the base of the LED bulbs.

images
 

Boombox

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I have found Lowes and Home Depot screw in LED's (standard base) to be terrible with RFI. The best ones so far for cheap are the wal mart great value brand believe it or not. They emit damn near nothing.

And people wonder why their radios and other wireless devices don't work... walk in with a spectrum analyzer and it looks like a forest.

Walmart is where I've gotten my own LED lights. The only radio that got interference from one of them was sitting next to one of those 70's style desk lamps with the long, metallic arm. I think that had more to do with the RFI than the bulb itself, although the bulb may have been a different brand which I got at Walmart. The two in my main DXing room are Walmart bulbs and only put out RFI if the radio is within a foot or so from the bulb. But a certain amount of that is expected, probably...
 

jackj

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I don't understand how installing a LED bulb in a garage door opener can reduce the remote's range. The light is only on after the opener is triggered and the bulb can't produce ANY RFI if it isn't on. I must confess that neither of my garage door openers have LED bulbs in them so logic might be failing me on this.
 

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Silent Key
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I don't understand how installing a LED bulb in a garage door opener can reduce the remote's range. The light is only on after the opener is triggered and the bulb can't produce ANY RFI if it isn't on. I must confess that neither of my garage door openers have LED bulbs in them so logic might be failing me on this.


Some electronic switching circuits pass a small amount of current even when turned off.
 
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