LED filament bulbs

Hi all,

So I was experimenting with some LED light bulbs lately, and seeing what effect they had on AM radio interference.  Some of the bulbs I purchased cause a huge amount of interference on my AM radio, while others had less, and some had none.

What I found interesting was that all of the LED "filament" bulbs I tried from various manufacturers had no interference.  

I emailed one of the smaller vendors who sold both regular LED bulbs and filament bulbs, and asked them about the difference in interference.  And here is the reply I got:

"The difference in interference levels is likely due to the power factor rating. Our filament A19 lamps have a power factor of 0.9, while the standard A19 lamps have a power factor of 0.6. We suspect that the way in which the internal LED driver draws current creates a small electric field that can be observed as interference over AM radio."

Just FYI.

BTW, the vendor in question is Waveform Lighting.  And these are the A19 bulbs, with the E26 base.

Marc

Interesting. One of my sensor lights outside blew a bulb and figured I would get 2 LED bulbs to replace them even though I hate LED lights. They are so freaking bright but outside I figure it would be OK. Going to replace a bug light we leave on all night when we go out as well.
I tried using an LED light to replace one of my interior lights but it was so harsh I couldn't take it, so I switched back to a GE Reveal lightbulb.
Trying to reduce electricity costs but LEDs are just too hard on the eyes for interior use

Filament warm white LED bulbs work for me; I can't handle the cold white light or FL tubes.
Had them for 3 years now and quite happy with them.

Never measured them though, might be the next project.

Ahh, well there are dimmer LED bulbs.  The Waveform Lighting "40 watt equivalent" LED filament bulb seems perfectly fine to me, and comes in color temperatures as low as 2400K!  Also on Amazon there is a "Bedtime bulb" that appears to be a filament bulb (it's frosted on the outside, so hard to say) that is about the same brightness and has a similar color temperature.  And both of these bulbs cause zero interference on my AM radio (unlike the non-filament bulbs).  So I think I'm going to start using these, as I've had all incandescent and/or halogen incandescent up to this point.

Marc
 

Also, based on that customer support email I got, I did some searching, and apparently to get "Energy Star" certified you have to have a power factor of at least 0.9, and a total harmonic distortion (THD) of less than 20%.  So this may be something to look for, and may be an indication of a less-noisy bulb.

I then found a BR30 LED reflector bulb with a power factor of 0.9, so I've ordered that and will test it with the AM Radio when it arrives.

Marc
 

> What about the affect on the eyes? Do these cause damage like regular LEDs?

Are we talking about eye damage from the excessive blue light in the spectral distribution?  If so, you can workaround this by:

1) buying lights with the highest CRI values possible, as I do not believe you can have an excessive blue light spike with a high CRI value.  Incandescent lights have a CRI value of 100, which is the highest possible value.  All of the LED bulbs I've been testing have a CRI value of 95, which is about as high as you can get with current LED technology.  Low values of CRI would be less than 80, and indeed you could have a fairly high blue light spike with that.

2) buying lights with a low as color temperature as possible.  LED lights are sold with color temperatures ranging from 2100k (warm) to 6500k (cool).  The higher color temperatures are more blueish in general.  It seems like people generally prefer the 2700 - 3000K range, which is generally more red/yellow than blue.  And 2700K is the color temperature of the old incandescent lights.

Marc
 

And, I guess one could just simply start by using LED bulbs in areas that you don't spend a lot of time looking at the light.  For example, exterior lighting, garage lighting, hallways, etc.  As I'm still using incandescent lights for these as well.

Marc

 

I tried Incandescent light bulb, but found I have to use 4 100W bulbs to achieve 200Lux which is lowest brightness level required for my eye to feel weel. That is too much..

I tried LED and FL too. Neither works. I feel headache. It is strange that I was fine with them two weeks ago.  I replaced my FL bulb with LED bulb two weeks ago to solve dry eye issue. But then I found I was untoreable to LED. I then switched back to FL, but headache is still there even though I was fine with FL two weeks ago. I am sure that I was fine with LED.

Seem EHS is getting worse and worse on me with time going on. But the progress is slow. Every half year or  
one year, I find I become sensitive to something which I wasn't in the past.  

Now the light issue becomes a big trouble to me. I have to use light to play with my computer. Even I don't work, I have to use computer to kill time. No friends, no families. If no computer, I don't know how to spend the day.