AM Radio Interference from (CFLs) Compact Fluorescent Light Bulbs

[TheRover]

I recently "upgraded" the lamp on my dresser beside my bed to an energy efficient 3-way (CFLs) Compact Fluorescent Light Bulb.

But, after installing the CFL 3-way, I noticed right away that I got interference while listening to my AM clock radio, also on the dresser, beside my bed.

I took out the CFL 3-way blub, and put back the incandescent 3-way bulb, and I now have no static interference.

I have CFL bulbs in many other places in the home, the bathroom, the bedroom overhead lights, the living room, etc.

I believe the proximity of the clock radio to to the lamp on the dresser is the culprit. They are both plugged into the same power strip as well. In any case, I cannot have the lamp and the radio any further apart, to be practically used on the dresser.

The CFL 3-way blub that I was using on the dresser lamp was a GE 2700K Soft White 600/1600/1500 lumens (15/25/32 watts) PC#78952 FLE32HT3/2D3/BX (Made In China).

 

[trojanrabbit]

A CFL (or for that matter an LED) bulb contains a switching power supply.

It will produce noise on the power line and radiate as well.

Some bulbs are noisier than others, maybe someone knows of quieter ones.

There are supposed to be EMI standards for these things, but I wonder how much a priority is given to enforcing those standards.

 

[Kmagrill]

Actually, I've taken several failed LED bulbs apart. They don't usually contain a switching power supply. Just a diode in series with a capacitor, a very small dropping resistor and a string of LEDs all in series like the old fashioned Christmas tree lights. One goes out and they all go out. One good aspect to this, otherwise pitiful, design is no rfi.

If it's any consolation, I think CFLs are a passing fad. That's just my opinion, of course. I base the notion on the fact that CFLs are expensive, very prone to early failure and can be replaced by LED lamps which consume only 15% of the energy, are cheaper to produce and can, if properly designed, last many times longer.

 

[nmoore6676]

A CFL is just a redesign of the traditional fluorescent tube which have for years been wiping out AM radio reception and even the old analog tvs at times. The new compact design features a switching power supply to replace the older ballast with starter circuits. You can try putting the two devices into separate plugs, you might need an extension cord and I would add a surge protector with RFI filtering to the radio side. Then you can try putting them physically as far apart as possible and nulling the radio's loop antenna to the lamp. Some bulbs (the most expensive) are less prone to cause interference. I have my clock radio installed as I've described and there is only a little buzz when the lamp is starting.

As for CFLs being a fad, the new Federal law outlawing the sale of incandescent bulbs is kicking into full gear so that is not likely. As of now LEDs are costly so it will be a while before they can replace the CFLs.

By the way the series design of the LEDs accomplishes the same thing as the series tree lights of yore. It allows each element to get the lower voltage they need without a transformer. The side benefit is you won't ever see the blackened segments I noticed in the first LED traffic signals. The burned out LEDS, usually grouped in one area would give an appearance like the old signals when the lens got covered with pigeon poop.

 

[bossbill]

For most parts of the country, CFLs are a scam. Incandescents produce a bit of heat which supplements your home heating system. They're not less efficient, it's just that the produce less light.

I've stocked up and am ready for the government ban. When incandescents are outlawed... only outlaws will have incandescents.

LEDs are dropping in price and will be our future, but be prepared to turn up your gas furnace a smidge.

 

[trojanrabbit]

Actually, I've taken several failed LED bulbs apart. They don't usually contain a switching power supply. Just a diode in series with a capacitor, a very small dropping resistor and a string of LEDs all in series like the old fashioned Christmas tree lights. One goes out and they all go out. One good aspect to this, otherwise pitiful, design is no rfi.

If it's any consolation, I think CFLs are a passing fad. That's just my opinion, of course. I base the notion on the fact that CFLs are expensive, very prone to early failure and can be replaced by LED lamps which consume only 15% of the energy, are cheaper to produce and can, if properly designed, last many times longer.

And I'm sure they had a nice 60Hz (maybe 120Hz) flicker as well.

Being in the professional LED lighting business, our products all have some sort of power supply to the LED string to regulate voltage and/or current (as many products are designed for worldwide line voltages). And yes, if the fixture is made of multiple strings of LEDs, if one fails (unless it shorts) that whole string will go out.

 

[Tom Wells]

Since the development of the lamp dimmer in the late 60s, nothing has been done to
ensure the manufactured devices meaningfully and usefully comply with part 15 regulations.

When written, they were only intended to apply to sinusoidal (analog) siganals.
Anything that switched was a different class entirely and needed different noise suppresion methods.
Since digital switching makes the same noise as actual physical contactors, it should be regulated by
laws that apply to that mode. But I'm not aware of any such laws requiring noise suppression on motor/etc
contactors.

At any rate, when part 15 laws were written, operating a transmitter in a manner which would create clipping and cutoff,
was considered something that just wasn't done; it wasn't good operating practice.

Yet such square waves are the heart of all new tech, which has for years been polluting radio.

This makes about 40 years now of the FCC doing nothing about simple lamp dimmers,
let alone the newer technologies like switching supplies.

Equally bad is the fact that many CFLs produce actual whining or buzzing audio in operation.

I'd like to see the FCC adress the very different nature of square-wave noise RF harmonics in new, specific
laws which include fines for manufacturers and industrial power users for not cleaning up emissions..

 

[Kmagrill]

I can buy 5 Watt LED bulbs today for under $10 that are about equivalent to 75W bulbs. I also have some 1.3W LED lamps in closets that are about the equivalent to 20W bulbs. They were $4. So, pricing is not quite competative yet, but certainly looks like it's getting there.

Regarding incandescents: an enterprising fellow in Europe is bringing in cases of them as miniature heaters after discovering that they meet the EU requirements for high efficiency electrical heaters. He sells them for $4eu each. I read that he sold out his first shipment of 3000 in a few hours. Entrapaneurs, there's a possible market for you.

 

[kenglish]

I'm still looking for a deserted island someplace, where I can see if my radio still works.
I can not find a place where the noise from these lamps, fluorescent lights, plasma TV sets, computers and routers, Cable TV leakage, etc has not decimated AM MW and HF reception. Even driving to work, I get overpowering noise every block or so.

Wish we still had an FCC.

 

[KeithE4]

For most parts of the country, CFLs are a scam. Incandescents produce a bit of heat which supplements your home heating system. They're not less efficient, it's just that the produce less light.

That's all well and good if you live in the northern latitudes during the winter. Old tube-type radios are good for additional heat as well. In summer, that is something you definitely don't want. In Arizona, Florida, southern California, and Hawaii, you never want it. ;D

I've stocked up and am ready for the government ban. When incandescents are outlawed... only outlaws will have incandescents.

LEDs are dropping in price and will be our future, but be prepared to turn up your gas furnace a smidge.

The few times I've had to deal with CFLs (I've never bought them, and won't, but have had to deal with them at work and at other peoples' homes), I've been very unimpressed, both with the quality of light (I hate fluorescent lighting!) and the generated noise.

I just used my last "regular" light bulb this week. When I go buy light bulbs again, I'll be trying the LEDs. In 35 years of working in the electronics industry, only rarely have I seen an LED go bad in a properly-designed circuit. They've been as close to foolproof as any electronic device I've ever worked with.

I'm waiting for someone to manufacture LED lighting that will replace the long-tube fluorescent bulbs - at least I've never seen them.

 

[cyberdad]

My two cents....

I prefer incandescents.

That said, I travel in my work, which means a lot of time in hotels....where CFL's have become pretty much universal. When I first started encountering CFLs in my travels....both in North America and in Europe....the CFL bulbs were guaranteed bigtime RFI producers. The trend, however, is that this is becoming less and less the case. Admittedly this is just my personal experience and certainly isn't scientific. But my takeaway is that some of the issues inherent with the earlier CFLs are being successfully addressed. And the light has gotten better, too.

I think the industry still has some work to do, but from what I can see, they're going in the right direction.

 

[trojanrabbit]

For most parts of the country, CFLs are a scam. Incandescents produce a bit of heat which supplements your home heating system. They're not less efficient, it's just that the produce less light.

That's all well and good if you live in the northern latitudes during the winter. Old tube-type radios are good for additional heat as well. In summer, that is something you definitely don't want. In Arizona, Florida, southern California, and Hawaii, you never want it. ;D

I've stocked up and am ready for the government ban. When incandescents are outlawed... only outlaws will have incandescents.

LEDs are dropping in price and will be our future, but be prepared to turn up your gas furnace a smidge.

The few times I've had to deal with CFLs (I've never bought them, and won't, but have had to deal with them at work and at other peoples' homes), I've been very unimpressed, both with the quality of light (I hate fluorescent lighting!) and the generated noise.

I just used my last "regular" light bulb this week. When I go buy light bulbs again, I'll be trying the LEDs. In 35 years of working in the electronics industry, only rarely have I seen an LED go bad in a properly-designed circuit. They've been as close to foolproof as any electronic device I've ever worked with.

I'm waiting for someone to manufacture LED lighting that will replace the long-tube fluorescent bulbs - at least I've never seen them.

There are T8, T10 and T12 LED replacement lamps, of course they are pricey. And a cursory googling shows that the ballast needs to be bypassed. Whether there are real drop-in replacements I don't know.

When I have been testing "lumenaires" I have tested to CISPR15 and FCC Part 15. As far as CISPR15 is concerned the limits are equivalent to CISPR22 Class B for ITE equipment except it only extends to 300MHz and there is an additional requirement for conducted emissions from 9 to 150 kHz. CISPR15 really needs to be updated though, because it concentrates on fluorescent fixtures with magnetic ballasts. Requiring an LED fixture to pass a low frequency magnetic emissions test is insane.

I do know that if a CFL is Energy Star rated then it must pass FCC Part 15 Class B. So maybe you might wish to check that on the bulb you're using.

Just for chuckles, I should take one of these new CFLs I'm holding in my hand and see if it really does pass.

 

[satech]

As for CFLs being a fad, the new Federal law outlawing the sale of incandescent bulbs is kicking into full gear so that is not likely.

Incandescent bulbs are not being "outlawed". Starting in 2012 with 75 and 100 watt bulbs and then again in 2014 with 40 to 60 watt bulbs, they are now required to be 25% more efficient. There are already new halogen incandescent bulbs on the market by Philips (EcoVantage), Sylvania (SuperSaver Halogen), and GE (Halogen) which meet these efficiency standards. These bulbs give the same warm glow as regular incandescent bulbs and produce no RFI. They are also mercury-free and fully dimmable, unlike CFLs.

Also, bulbs below 40 watts and above 100 watts will not be affected by the new efficiency standards.

 

[jonbruce]

From what I have heard the clear incandescent "tower light" bulbs will still be leagally sold. I have been using them at home for decades.

 

[satech]

From what I have heard the clear incandescent "tower light" bulbs will still be leagally sold. I have been using them at home for decades.

This web page has full details on the long list of lamp types which are exempted from the 2012-2014 efficiency requirements:

http://donklipstein.com/incban.html

Basically, anything other than a standard household 120-volt, 40- to 100-watt incandescent bulb is exempted from the efficiency requirements -- including 3-way, appliance, candelabra, globe "vanity", and "rough service" bulbs.

 

[OKCRadioGuy]

"Wish we still had an FCC."

Oh, we do! It's now the Federal Check Cashers! Get a piece of paper out of order in the public file or forget to log something on the EAS and they'll be right there to take your check. Got a ligit interference complaint? Well now... Best of luck on that! If a guy is real lucky, they might be able to find someone in the EB that still knows how to DF interference that hasn't already retired out. I agree, the FCC as we have known it doesn't exist anymore. It's all about figuring out how to make money, one way or another, with them anymore. Sad... To be specific, this is 100 percent the fault of Congress who demands this version of the FCC. It was all downhill when the auctions started. Now all we have are lawyers and paper-pushers that are there to faciliate making money and pushing paper for the cell industry.

 

[TomZ]

Michael Powell was the first Chairman to organize the extortion... and I'll bet his lifestyle shows it.

 

[boiseengineer]

Remember that the FCC made all services 100 KHz to light secondary to power line delivered internet.

 

[OKCRadioGuy]

Little Powell certianly was one of the worst ones. Terrible would be an understatement. The current clown isn't any better either.

 

[nmoore6676]

As for CFLs being a fad, the new Federal law outlawing the sale of incandescent bulbs is kicking into full gear so that is not likely.

Incandescent bulbs are not being "outlawed". Starting in 2012 with 75 and 100 watt bulbs and then again in 2014 with 40 to 60 watt bulbs, they are now required to be 25% more efficient. There are already new halogen incandescent bulbs on the market by Philips (EcoVantage), Sylvania (SuperSaver Halogen), and GE (Halogen) which meet these efficiency standards. These bulbs give the same warm glow as regular incandescent bulbs and produce no RFI. They are also mercury-free and fully dimmable, unlike CFLs.

Also, bulbs below 40 watts and above 100 watts will not be affected by the new efficiency standards.

While "outlawed" may have been an overstatement the fact remains that shelf space in the store of your choice devoted to incandescent lamps has been and still is shrinking. I read the so called "standards' and my head still hurts. Perhaps retailers and manufacturers are playing it safe and not wanting to chance accused of selling the wrong products. Fines have become a revenue stream of choice lately after all. In any event manufactures are closing facilities devoted to the old style incandescent bulbs.

As for halogen lamps, I have used them for TV studio applications and I am familiar with them. The smaller household varieties which I've seen and experienced produce extreme even dangerous amounts of heat. So unless the newer models have significantly addressed that issue I won't be converting to them. I have no problems with CFL bulbs save the interference issue and the disposal aspect. I would welcome newer LED and other technologies.

The fact remains that government regulation and what might be deliberate manipulation of the public understanding is driving the consumer to the newer and more expensive as well as somewhat problematic new lamp technology.