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Title: Light Bulb RF Noise Post by: WD8BIL on April 10, 2007, 02:57:57 PM Had a chance to run some scans on the new bulbs of the future. This sample I have is a sylvania 23 watter (blue trace). The red trace is a 100W GE normal light bulb.
The lower limit line is the FCC Part 15 Class B limit for conducted noise. Title: Re: Light Bulb RF Noise Post by: WA1GFZ on April 10, 2007, 03:58:48 PM Holy crap that sucks
40 dB uv is about S9 Title: Re: Light Bulb RF Noise Post by: AF9J on April 10, 2007, 04:32:47 PM You know something, that makes sense. My apartment building has mini flourescents (you know, the ones that are meant as replacements for incandescents in your lamps, etc,). My noise level is at least 10 to 15 over 9! on 80 & 160, and even S6 to S7 on 20m! That's awful!
Ellen - AF9J Title: Re: Light Bulb RF Noise Post by: flintstone mop on April 10, 2007, 04:49:36 PM Oh My Gawd
I found an under the shelf flourescent wipe out 160M, from a next door neighbor 50 feet away! The lady was very cooperative even though I wiped out their TV when I was on 80M AM. A simple common mode filter on the VCR took care of that. Fred Title: Re: Light Bulb RF Noise Post by: WA1GFZ on April 10, 2007, 05:11:09 PM WOW Fred,
I was planning under shelf lights in new place guess I'll buy a low voltage LED system. This is worse than BPL Title: Re: Light Bulb RF Noise Post by: k4kyv on April 10, 2007, 05:21:13 PM Makes me glad that the nearest house from me is over 500 ft. away.
I tried a compact fluorescent in the shack and immediately yanked it out as soon as I heard the noise. I think I'm still getting QRM from someone's touch lamp. It's weak, but puts an annoying birdie right on top of the AM signals I hear near 1985, and another one falls right on 1885, plus additional ones about ever 50 kHz from BC band up past 3 mHz. I hope my 160m signal is making the thing go spastic whenever I transmit. They have loads of made-in-China touch switches in stock at Lowe's and Home Cheapo. Not a single one of the damn things has the required FCC Part 15 notice attached. Title: Re: Light Bulb RF Noise Post by: W1RKW on April 10, 2007, 06:08:55 PM That's strange. 80% of the lights in my household have compact flourescents lights (CFL). With the exception of one CFL I have no noise on my shack receivers. The dimmer on the chandelier in the dining room on the other hand is the biggest offender.
Title: Re: Light Bulb RF Noise Post by: wb1aij on April 10, 2007, 06:11:43 PM Boy, the Hams in the days before electricity was invented were LUCKY. Imagine how quiet the bands were before lights,motors, VCRs, TVs, and all of those other noise generators. Must have been nice.
Title: Re: Light Bulb RF Noise Post by: Tom WA3KLR on April 10, 2007, 06:15:25 PM I have some of the CFLs here. I did notice the RFI noise but only with the ones in the master bedroom where my Sony 2010 portable is. Noise is not too bad considering the distance.
I noticed that sometimes I can flick the light switch off and back on real quick and the noise goes away even though the bulb is running. Below is a photo of the p.c.b. from the base of a CFL. I tore the assembly apart after the bulb became intermittant. I think that I stressed the bulb due to swapping it around to many sockets and turning the bulb in and out by the tube. Don't do this! Grip the CFL by the plastic base. The p.c.b. has these parts: 1 PTC thermistor 1 inductor 1 transformer 6 film caps. 6 diodes 1 resistor 1 toroid 2 power transistors 1 22uf/200V aluminum electrolytic cap. Title: Re: Light Bulb RF Noise Post by: AF9J on April 10, 2007, 06:32:07 PM Hi Tom,
The ones in my building, are not your typical coiled up CFLs. I don't even think the base is compatible with a normal lamp socket. I think it's a plug in type CFL. Basically, they're configured like a trombone slide. I've seen transformers next to the ones in the basement laundromat, that are installed bare (without housings around them). I just took a look at GE's website. The bulbs in the CFLs in my building, are of the T4 or T5 type. They're up and down the hallways of the 1st floor, 2nd floor, and basement, and used in outdoor lights that are basically located below my antenna. Ugh!! 73, Ellen - AF9J Title: Re: Light Bulb RF Noise Post by: KB2WIG on April 10, 2007, 07:10:54 PM "The ones in my building, are not your typical coiled up CFLs"
Some of the bigger lectrical 'users' run 277 volt lighting sys...... check out the base of one of the units and look for the majick '277' klc Title: Re: Light Bulb RF Noise Post by: Bill, KD0HG on April 10, 2007, 07:16:28 PM Those CFL bulbs *without* a screw-in base, with just pins on the end use either an electronic ballast or a passive inductive ballast, either type is part of the lamp housing itself. We have about 30-40 of the 9-watt CFLs in our offices. Passive magnetic ballasts would be too large and impractible for use in the screw-base CFLs.
I once took a look at the neutral to ground (building frame) noise in my office...Those switcher power supplies in all of our computers put *volts* of RF hash on the AC mains. I've had to use electrostatically shielded transformers in some of the studios to provide a truly balanced and more noise-free AC power source that's not referenced to ground. The ground prong on those outlets is isolated, going directly to the steel building frame, not back to the load centers. Title: Re: Light Bulb RF Noise Post by: W2JBL on April 10, 2007, 08:38:38 PM i first encountered those bulbs while on a "black ops" mission operating from a hotel room. the initial plan called for an indoor antenna taped to the ceiling of the room. the 30 over noise was so bad i could barely hear the "subject" and had to risk compromising the mission by damaging the window to get it open ("saftey" window, won't open), ripping away the fixed screen and running a wire outside the building. the bulbs made wicked noise on 75 and 40. there was a big type acceptance flap over those bulbs back in the 90's by the way. we put those things in where i work and a few days later i noticed the noise floor on 46MHZ was up around -70DBM and couldn't hear squat...so we went back to real bulbs. now we have Gore and the treehuggers trying to ban incandescent bulbs (like VK land) here... maybe we can convince them the RF "radiation" from compact flourescents is going to cause brain cancer, like shoe phones!
Title: Re: Light Bulb RF Noise Post by: AB1GX on April 10, 2007, 08:49:25 PM My experience is that standard FLs are much, much worse noise generators than the CFLs. The newest CFLs I tried don't seem all that bad.
Title: Re: Light Bulb RF Noise Post by: WD8BIL on April 10, 2007, 10:22:49 PM Keep in mind that was CONDUCTED noise placed on the AC power lines.
I may get some time tomorrow to run some scans on the radiated electric and magnetic fields at 3 meters. We're setting up a temperary shielded room for some visiting engineers from one of our companies other facilities. They (being west coasters) were wondering why I didn't have any "green" light bulbs in the EMC labs !!! Geeezzz.... I guess they know why now !! Title: Re: Light Bulb RF Noise Post by: WA3VJB on April 11, 2007, 05:25:02 AM Very interesting research Buddly, please post more as you continue. When CFLs first emerged from the laboratory there was significant concern they would be noise generators on HF. Manufacturers initially seemed to take that into consideration to help win market acceptance and FCC approval (in whatever order).
Today I wonder if anyone has one of those older CFLs with low hours to do a comparison run to the newest stuff. As a cost-cutting move, I thought the QC might be allowed to slip among factories in the third-world countries making these things. The retail price has already dropped in half, and one wonders if its from more than economy-of-scale as production ramps up. Ideally, I'd like to see high output, color corrected LED technology replace CFLs. It's amazing how much light they're already squeezing out of them things. I put a 3W single LED bulb in my 3-D MagLite, and except for the bluish cast, there's lots of lumens pouring out of there. Quote Boy, the Hams in the days before electricity was invented were LUCKY Yeah, I usually shut the AC Mains circuit breaker off when I get on the air. It really quiets things down. Title: Re: Light Bulb RF Noise Post by: AF9J on April 11, 2007, 06:53:28 AM I have some spare time, before I leave for work, so I took a look at the CFLs in the hallway, and the basement of my apartment building. The ones in the hallway seem to have an integral base, with the ballast circuitry in the base. The ones in the basement (one of which was listed as a Norelco PL9), are a bit more exposed (they're not in lamp housings). They seem to have a step-up transformer feeding into the CFL assembly. I'm not sure if the hallway ones are the same (they're a bit smaller, but it's possible that there is a transformer hidden in the lamp housing).
I've always had problems with these things, but they've gotten worse over the past 3 months or so. This seems to coincide with the time that they replaced the incandescents in the outdoor lights, with CFLs. One of them is of the "lantern on a pole type that's very popular for outdoor lights. It's located maybe 40 feet or so from my antenna, on a post in the back yard (which my apartment faces). But, the kicker, is that I also have the noise during the daytime, so I don't know if it's: A.) the timer for this light; B.) The lamp housing isn't weather sealed too well (I've seen the ones by the entrances, and their weather sealing is a joke), and moisture is causing problems in the CFL circuitry, or the wiring; C.) one of my neighbors now has a noisemaker in their apartment. 73, Ellen - AF9J Title: Re: Light Bulb RF Noise Post by: Ian VK3KRI on April 11, 2007, 06:57:06 AM The p.c.b. has these parts: 1 PTC thermistor 1 inductor 1 transformer 6 film caps. 6 diodes 1 resistor 1 toroid 2 power transistors 1 22uf/200V aluminum electrolytic cap. So who's the first to build a transmitter out of a light bulb ! Title: Re: Light Bulb RF Noise Post by: WA1GFZ on April 11, 2007, 09:24:10 AM I shared the data with my EMI gang sounds like a science project is in our future. I didn't notice it was a CE scan....at least it will be lower as RE. I will not have any glow tubes in my house. I told the XYL we will buy a lifetime supply if some moron passes a law. Bud you might try snapping a bead on the power lead to see if it helps. Most outlet boxes are big enough to hold a bead on the leads to limit common mode CE on the power lines. It might be an easy fix. Bud see if you can measure the RE off the bulb without exposed power leads across the bench ground plane. Maybe copper tape them to the plane to see if the RE is off the power leads or the bulb. fc
Title: Re: Light Bulb RF Noise Post by: WD8BIL on April 11, 2007, 10:02:59 AM If I ignore the .8 meter rule Frank I can set the socket mounting plate right on the center access hole of the turntable and bury the leads below the GP. Looks like lunch will be fun today !
Title: Re: Light Bulb RF Noise Post by: WA1GFZ on April 11, 2007, 11:27:39 AM That sounds like a good test. fc
Title: Re: Light Bulb RF Noise Post by: K6JEK on April 11, 2007, 11:33:43 PM Had a chance to run some scans on the new bulbs of the future. This sample I have is a sylvania 23 watter (blue trace). The red trace is a 100W GE normal light bulb. The lower limit line is the FCC Part 15 Class B limit for conducted noise. I infer this is a CFL. I think the bulbs of the future will be LEDs similar to this one http://movie.diginfo.tv/2007/03/07/index.php?ofs=0&pid=3 I've been informed by my neighbor who designs chips for bigger versions of LED fixtures that the ones he's working on have four (count em, 1,2,3,4) switching power supplies in a single fixture. He told me what they were all for but I was too dumbfounded to listen. They are getting 70 lumens/watt, nearly 10x incandescent, but the big draw is 50,000 hours expected life. Do I have too many zeros? Anyway, much more than anything else. But four switching power supplies? Oof. Title: Re: Light Bulb RF Noise Post by: AF9J on April 12, 2007, 06:36:33 AM 50,000 hours? That's MY kind of light. But, I didn't know they used switching power supplies for LED lights. We all know that if switching power supplies are built & designed properly, they can be pretty quiet. BUT, if aren't built or designed properly, they can be extremely noisy.
73, Ellen - AF9J Title: Re: Light Bulb RF Noise Post by: W1VD on April 12, 2007, 08:51:58 AM Bud
If you have time...could you have a look in the VLF and LF range as well? I do LF stuff and those bulbs are particularly bad down there - conducted noise is the big problem. Sure hope the 'greenie weenies' can be stopped from banning incandescents. Jay W1VD Title: Re: Light Bulb RF Noise Post by: Tom WA3KLR on April 12, 2007, 10:07:31 AM The 60 Watt frosted bulbs I have on hand come out to 13.7 Lumens per Watt.
So 70 Lumens per Watt is a 5 X improvement. The LEDs and the CFL are about 3 X more efficient than the incandescents. The LED and CFL manufacturers usually say 4X though. Title: Re: Light Bulb RF Noise Post by: Bill, KD0HG on April 12, 2007, 12:38:14 PM The color spectrum of the currently-available white LEDs is awful.
Don't know why, but they need to fix it. They hurt my eyes. Title: Re: Light Bulb RF Noise Post by: Tom WA3KLR on April 12, 2007, 01:48:11 PM White LEDs are made 2 ways. One is they use a blue LED and phosphors. The other way is to use 3 LEDs - blue, green and red.
Below is a table that was in the November 16, 2006 issue of Electronic Design. The table comes from Cree, who is one of the leaders in producing compound semiconductors in the U.S. LEDs are compound semiconductors. Cree says that up to half of the Lumens from a light source is lost in the fixture design. Hence the "Usable Output" column. Their LEDS are the only ones on the list too. (Since LEDs radiate as a hemispherical source, I wonder if we will have LED panels on our ceilings in the future.) Light-source Type Luminous efficiency Usable Ouput Lifetime (Lm/W) (Lm/W) (hours) incandescent lamps 17 10 - 17 3000 halogen lamp 20 12 - 20 10,000 Cree XLamp 7090 XR 47 47 >50,000 (color and white) T12 fluorescent lamp 60 45 - 50 20,000 metal-halide lamp 70 <40 5,000 - 15,000 Cree XLamp 7090 XR-E 71 71 >50,000 (white) T8 fluorescent lamp 74 55 - 60 20,000 high-pressure sodium lamp 91 <50 20,000 - 24,000 T5 fluorescent lamp 100 80 20,000 low-pressure sodium lamp 120 65 - 70 18,000 Title: Re: Light Bulb RF Noise Post by: WA1GFZ on April 12, 2007, 04:20:27 PM When it isn't too cold out I don't mind if the kids leave lights on because they will heat up a room keeping the heat off so I take advantage of inefficient glow lamps. Flat panel LEDs sound cool for the ceiling.
Title: Re: Light Bulb RF Noise Post by: W3RSW on April 12, 2007, 04:47:32 PM Didn't we cover a lot of this just a week or so ago?I
I think the bulb components and transmitter build were mentioned before. Ooooh, a hissy. - Uh, sorry. Well they say that's the second thing to go.... Umm, back on topic. I suppose someone else here has already pulled one of these lamps apart to see what's inside. I cut my finger breaking the spiral glass tube, of course, in getting the d**n thing apart. Jeeze, enough parts to build a radio! Get three or four of the earlier models and you can have a complete shack. In one 13 watt Phillips I see one transformer, one 33uf/200v 105deg.C electrolytic, 3 ea. 1n4005 diodes (if I read em right), 2 more switching diodes in small glass pkg., 2 Motorola T5N25E 3pin regulators or some sort of push pull osc. transistors w/ the mounting hole tabs cut off, bunches of 1kv square package capacitors and resistors, e.g., MKP 6n8k@1kv, and of course the printed circuit board measuring about 1.9 in. dia. The transformer complete with iron core appears to be 3 pins (ct) and 2 pins out, and measures abt. 0.7" high, 0.6 wide and 0.4 thick. Well that'd be good for a class E kilowatt : ) Can you imagine the infrastructure necessary to manufacture these things by the billions, the heavy metals containment, disposal processes that would be necessary if done in the supposedly 'green' perfect world desired. Reminds me of all the sci-fi, "Cover the World with photoelectric cells power generator" scenarios. Not mentioned, of course is the following mass world pollution from kilotons of seminconductor doping elements, arsnic, etc. Shadowing of the ground in great swaths also will have some pretty interesting effects. Yes another, not thought out at all, political solution containing many levels of unintended consequences. Of course, all will self collapse long before we get to the one billion mark. Well, I stand corrected... look at McDonalds. Title: Re: Light Bulb RF Noise Post by: WA1GFZ on April 12, 2007, 08:34:01 PM yes but Bud provided real test data for conducted emissions he measured coming off the little crap generator.
Title: Re: Light Bulb RF Noise Post by: WD8BIL on April 12, 2007, 09:45:35 PM Well... today was a busy day but tomorrow(friday) will be quite a bit slower.
I shud be able to complete the LF, HF and VHF radiated scans. I'll probably do the 10Khz to 500Khz Telchordia CE scans too. Stay tuned. Title: Re: Light Bulb RF Noise Post by: W3RSW on April 13, 2007, 08:14:29 AM I agree. The spectral scans are scary and contain very relevant information for us.
Could you please also run scans on light dimmers? My dining room light and kitchen are controlled and similar to what was previously mentioned, they're the dirtiest RF thing in the house, way dirtier than Phillips bulbs. BTW just holding my cell phone, even when only receiving, next to any radio, from bat. portable am/fm to my 75a2 generates one good mysterious SciFi sounding howl. Wonder what several million of these do the the radiosphere? Talk about uncontrolled oscillators. Title: Re: Light Bulb RF Noise Post by: Bill, KD0HG on April 13, 2007, 10:44:00 AM I'm sure they *could* manufacture quieter lights and dimmers, but the manufacturers aren't about to spend a penny more than the minimum needed to meet FCC requirements. It's the FCC that's the problem here, and they're not exactly under major public pressure to tighten the Part 15 rules...
Title: Re: Light Bulb RF Noise Post by: WA1GFZ on April 13, 2007, 11:34:18 AM The best way to eliminate dimmer noise is to never install them.
Title: Re: Light Bulb RF Noise Post by: AF9J on April 13, 2007, 12:07:23 PM Yes, part of the issue is that. The other part of the issue, is the fact, that unless representative units sent for compliance, are basically off of the production floor, you can't even say that these items generally meet Part 15. Oftentimes, items that are sent for compliance are pre-production, prototypes, or first run items, that are either built to a higher standard than the typical production item, or with greater attention to quality than the typical production item. in order to pass certification or compliance. I've seen this happen with samples or early runs we've received from some suppliers we've had quality issues with. We've caught these issues with regular inspection and testing of items. The FCC doesn't do this, due to manpower and the cost of what doing periodic recertifcation would be for them. So, the CFAs we buy, could have some differences from those that were certified to Part 15, and not even be compliant.
Ellen - AF9J I'm sure they *could* manufacture quieter lights and dimmers, but the manufacturers aren't about to spend a penny more than the minimum needed to meet FCC requirements. It's the FCC that's the problem here, and they're not exactly under major public pressure to tighten the Part 15 rules... Title: Re: Light Bulb RF Noise Post by: Bill, KD0HG on April 13, 2007, 12:46:45 PM Ellen, that's almost a different issue. If the item is designed and manufactured in full compliance with current regulations, and causes harmful interference, it's an FCC regulatory issue. If the same item is made without regard to quality control and violates Part 15, then the device is unlawful to use and the manufacturer should held accountable, and should be required to recall the product.
For the subject at hand, it's speculation as to whether the devices are or are not in violation of Part 15 standards. Perhaps this is a role the ARRL or someone civic-minded should take on; running tests as Bud is doing and reporting violators to the Feds...Because if we don't do that, who else will? Title: Re: Light Bulb RF Noise Post by: WD8BIL on April 13, 2007, 01:06:39 PM Let's look at the first scan a minute.(as other scans are running right now)
FCC Part 15 requirements for this product would be the Class B limits for residential usage. The FCC frequencies start at 450Khz. The freqs below 450 are EN55022(Europe) standards. At @700Khz, 1.2 and 1.4Mhz the data says this sample is a pass. By the skin of it's teeth.... but a pass non the less. BUT... as was pointed out, at 40dbuv we have an S9 signal source pumping crap onto the AC lines. Now.... 99% of the public will never become concerned with this. We, as radio enthusiasts(sp), become concerned because it effects our passion. These exercises are not meant to lead a campaign but simply to add info to a previous discussion. Title: Re: Light Bulb RF Noise Post by: k4kyv on April 13, 2007, 01:34:01 PM What about touch lamps and touch type wall switches? Those things wipe out wide swaths of spectrum over extended distances with garbage, and the ones I have seen for sale at places like Lowe's and Home Cheapo are Chinese imports that do not even have the required FCC Part 15 tag attached.
Title: Re: Light Bulb RF Noise Post by: Bill, KD0HG on April 13, 2007, 01:41:22 PM Bud, then perhaps it's time the League (or other interested person(s)) should petition the FCC to change the Part 15 regulations as the lights can interfere with licensed radio services. As I previously wrote, there's no question that they could be engineered to be cleaner.
One aspect that bears more scrutiny is why some users are receiving unacceptable levels of interference from CFLs, while others, myself included, do not. I can hear our light dimmers to varying degrees, but I can't hear any hash -at all- from the dozen or so CFLs in use in my house. Is it variations between brands, designs, grounding of the ham station or AC mains, ground loops, maybe the use of metallic conduit or the proximity of the ham antenna? I dunno. Title: Re: Light Bulb RF Noise Post by: Bill, KD0HG on April 13, 2007, 01:43:23 PM What about touch lamps and touch type wall switches? Those things wipe out wide swaths of spectrum over extended distances with garbage, and the ones I have seen for sale at places like Lowe's and Home Cheapo are Chinese imports that do not even have the required FCC Part 15 tag attached. Then report the things and their retailers to the FCC, Don! Title: Re: Light Bulb RF Noise Post by: WA3VJB on April 13, 2007, 03:08:53 PM We've got a half dozen CFLs in the house and out back, and I don't hear them either, and I've walked around with a portable just to sniffum.
I do hear the old style fluorescent tubes, they ARE nasty, and also an unfiltered dimmer on a floor lamp. Wall dimmers are filtered Lutrons, vy quiet, with a good aluminum heat sink besides. I've had a switched power supply, an old thing that used to run an old laptop, dirty as hell all over HF if you were within 5 feet. Title: Re: Light Bulb RF Noise Post by: WD8BIL on April 13, 2007, 03:15:44 PM Actually Bill, Paul, that isn't too surprising. Below is the radiated emissions on this sample taken with an active rod antenna at 3 meters. Telchordia standard GR1089.
It's pretty broadbanded and mostly below say... 4Mhz. The field intensity is relatively low. Most likely due to the lack of radiating structure within the bulb. Conductors and componants are just too small to form any significant fields. I do have more detailed CE (conducted emissions) scans I'll post later tonite. They, on the other hand, are pretty interesting. CE is where we're gonna see the worst. Oh.... the purple scan is a reference. It is the chamber ambient with the power to the lamp turned on but the lamp has been unscrewed. And before anyone says anything about how noisy the chamber is.... The scan starts at +20dbuv because of the correction factors needed to comp. for the active rod antenna. Title: Re: Light Bulb RF Noise Post by: AF9J on April 13, 2007, 03:36:15 PM Good point Bill,
I agree. But I guess I wonder how well they really enforce Part 15 Compliance. Nevertheless, I stand corrected. Ellen - AF9J Ellen, that's almost a different issue. If the item is designed and manufactured in full compliance with current regulations, and causes harmful interference, it's an FCC regulatory issue. If the same item is made without regard to quality control and violates Part 15, then the device is unlawful to use and the manufacturer should held accountable, and should be required to recall the product. For the subject at hand, it's speculation as to whether the devices are or are not in violation of Part 15 standards. Perhaps this is a role the ARRL or someone civic-minded should take on; running tests as Bud is doing and reporting violators to the Feds...Because if we don't do that, who else will? Title: Re: Light Bulb RF Noise Post by: WD8BIL on April 13, 2007, 06:49:47 PM OK... here's some more pictures.
Low frequency CE and band specific CE for 160, 75/80 and 40 meters. Some of the spikes look very familiar to my receiver. Hmmmmm Title: Re: Light Bulb RF Noise Post by: WD8BIL on April 13, 2007, 06:55:24 PM And 40 !
The CE scans were done with an Agilent 7404A EMI analyzer, Solar 200amp 50uh LISNs and an HP 10db transient limiter. The 10db attenuation from the limiter is compensated for in the results. The RE scans were done on an Electrometric EMC30 EMI Receiver using an EMCO Active Vertical Rod antenna and 30 meters (standard) 9913 mil spec. Distance was 3 meters. Title: Re: Light Bulb RF Noise Post by: WA1GFZ on April 13, 2007, 08:38:29 PM Bud,
Was that just the bulb or bulb plus 2 meters of cable on the bench? Never in my QTH. That is pretty strapping for 3 m distance. That active rod is a nice ant we have a couple of them. Part 15 that is nothing Hams would prefer UK DEF STAN limits...or 461e USAF external fixed wing. Title: Re: Light Bulb RF Noise Post by: WD8BIL on April 13, 2007, 10:10:14 PM Frank.... the RE scans were done as we discussed earlier. The socket mounting plate covered the access hole in the turntable so I got some 2" copper tape and sealed the wires under the turntable/GP. That's just the lightbulb, socket and about 8" of wire.
Title: Re: Light Bulb RF Noise Post by: WD8BIL on April 13, 2007, 10:19:24 PM Quote But I guess I wonder how well they really enforce Part 15 Compliance. Nevertheless, I stand corrected. As in any interference issue Ellen, they usually instruct the offending party to contact the complaintant and mutually work it out. The FCC usually won't step in until an impass is reached or the offending party flat out refuses to rectify the problem. They then can order a shutdown of the offending system until repaired and/or level fines. In the telco industry we cannot market a power system without FCC Part 15 certification. One sample PRODUCTION system must be certified by a third party FCC certified lab. My lab is actually a pre-compliance lab specifically for our companies products. It's good to know our systems are compliant before we drop $60 - $100K for third party certification. Title: Re: Light Bulb RF Noise Post by: AF9J on April 14, 2007, 12:47:20 AM I figured as much, that you were working in an RF Lab environment Bud. But, what about companies like GE for instance, where RF emissions for many of the items they make, are incidental/unintended in nature. In other words, they are not Telecom in nature as an industry. Since many of their items are made overseas, how well, do we really guarantee that these items (past the initial samples that were used to check Part 15 compliance), are meeting Part 15. The company I work for purchases some of it's stuff from overseas. I won't lie, some of the quality is pretty nasty. I remember a few comments made by Don stating about lamp dimmers sold at Home Depot, made in China, that were not marked as being Part 15 compliant. Since they aren't marked as such, how do we know any effort was made to meet compliance with them.
It's 11:30 PM. I've just spent the last frustrating 45 minutes, trying to null out my nasty hum, that's either from powerlines, or CFLs. Even with an active noise cancelling antenna, the best I can do, is drop my noise from 10 over 9, to about S8. I'm at a loss. I don't know if it's a case of me living in a noise saturated environment (I have 2 significant sources: tons of CFLs; and powerlines [both the typical residential service lines, and 250 kV transfer lines]), in which case I'm out of luck, or I'm approaching the noise source issue wrong. 73, Ellen - AF9J Title: Re: Light Bulb RF Noise Post by: WA1GFZ on April 14, 2007, 08:54:46 PM Wow Bud, so that is RE right off the bulb. Part 15 spec limits are pretty high when you look at a receiver noise floor. I guess I will never use these in my house.
I hope an S9 signal doesn't radiate well enough off my neighbors wiring for me to hear it. It would be interesting to lay out a couple meters of romex on the bench and see how high it goes then add a common mode choke (snap on core) to see the effect. Title: Re: Light Bulb RF Noise Post by: WA3VJB on April 16, 2007, 04:09:36 AM What's "Part 18 ?"
OK, found it. • FCC Part 18 - Industrial Scientific Medical (ISM) Just bought a few CFL's made in communist China and there's a label on there saying they comply with it, but that they also can generate RF noise from ".435-30Mhz," and that the bulbs should be kept a way from "critical maritime interests." Will try to scan the label in, rather disturbing. Radios are NOT catching noise, so maybe it's boilerplate from the attorneys. Title: Re: Light Bulb RF Noise Post by: N3DRB The Derb on April 16, 2007, 06:59:58 AM All hail to the greater glory of China. :P
Title: Re: Light Bulb RF Noise Post by: WA1GFZ on April 16, 2007, 08:38:22 AM I bet it was scanned off a CD player tag and printed on the bulbs.
Title: Re: Light Bulb RF Noise Post by: Bill, KD0HG on April 16, 2007, 12:41:56 PM I remember a few comments made by Don stating about lamp dimmers sold at Home Depot, made in China, that were not marked as being Part 15 compliant. Since they aren't marked as such, how do we know any effort was made to meet compliance with them. Then there are those regulations concerning toxic material in foodstuffs shipped here from China... Title: Re: Light Bulb RF Noise Post by: WA1GFZ on April 16, 2007, 02:43:12 PM ethics not high on their list since they are dealing with whores anyway
Title: Re: Light Bulb RF Noise Post by: WD8BIL on April 20, 2007, 09:46:11 AM Quote I figured as much, that you were working in an RF Lab environment Bud. But, what about companies like GE for instance, where RF emissions for many of the items they make, are incidental/unintended in nature. There are other parts of CFR 47 that cover these Ellen. Part 18, Part 68 for example. It runs the gammet from air systems to zebra fa.... uhh... emissions ! ;D Title: Re: Light Bulb RF Noise Post by: AF9J on April 20, 2007, 10:22:52 AM Good Morning Bud,
Thanks for the info. As I mentioned in another post, it's looking like my noise is mainly powerline related (gotta love those 250 kV transfer lines!, especially when they're only 120 yards or so from where you live, and it rains, snows, or gets cold outside), and not related to CFLs. Although, I am almost tempted to grab my FT-897D (I have an internal 4.5 amp-hr NiMH battery pack in it, and it's pretty portable), hook up a sniffer antenna, and walk the halls to check out the noise from the CFLs. 73, Ellen - AF9J Slaving away at work Title: Re: Light Bulb RF Noise Post by: AF9J on April 20, 2007, 12:31:14 PM Bud, AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
You might want to take a look on e-ham, and add your 2 cents worth to the discussion, since you've done a fair amount of research on the noise issues with the CFLs. They just started a thread this morning on CFL noise, and it's already pretty long. Here's the URL: http://www.eham.net/articles/16365 73, Ellen - AF9J |