A cute animation showing boiling electrons off of a hot filament, in context of starting a fluorescent lamp.
I never knew electrons had arms and legs and eyes.
But wait! The Mercury ions have caps and clubs to "direct traffic"! Later they get over-energetic!
If you like Closed Captioning, this one is bad. The phosphor is checked for "sickness". And instead of "she is", "Jesus"! Must be voice recognition on a voice the system has trouble with.
But wait! The Mercury ions have caps and clubs to "direct traffic"! Later they get over-energetic!
If you like Closed Captioning, this one is bad. The phosphor is checked for "sickness". And instead of "she is", "Jesus"! Must be voice recognition on a voice the system has trouble with.
I liked the part where electrons are given a size, although that is the billiard ball way I was taught growing up. As if quantum mechanics, from the 20s and 30s had never happened.
John Wheeler said that there's only one electron, which bounces forward and backwards through time. This explains why all electrons look alike.
All good fortune,
Chris
John Wheeler said that there's only one electron, which bounces forward and backwards through time. This explains why all electrons look alike.
All good fortune,
Chris
I can tell you Osvaldo that fluoro lamps have the worst light spectrum available, halogen lamps the best and in second place traditional lamps and in third place white-LED lamps.
Fluorescent lamps do not have a continuous spectrum, which is why it is so bad.
Fluorescent lamps do not have a continuous spectrum, which is why it is so bad.
Yes, I know that. But mine are 20 years old, run with electromagnetic ballast and only replaced 2 of 5 in my home durind this time. Over it, they generate low EMI unlike electronic ballast and leds. As ham radio from 1987, I have a strong interference in the 2mts band (144MHz !!!) when led lighting at the street start to glow. Below two 105W lamps.
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I do not have a problem with LED lighting. I just have a problem with how we power them.
They are so much more efficient than other types that it becomes a minor issue.
Motors require much more power, and consume about half of all electrical power used for any purpose.
We do have to have lighting, and this is by far the best method.
TLDR: Get high CRI (color rendering index, aka light quality) spec, use adequate heat sinking and separate driver from heat source.
Good sir! Can I persuade you that PROPERLY implemented LEDs can bigly out perform on several metrics. On the reliability front I don't think they have a parallel. I have been DIYing LEDs for about ten years and lit my shop with them. I left them on for five years straight without a single failure. Actually, I have never had a single LED homebrew fail; it's just that after five years I sopped keeping track and started turning them off out of respect for the neighbors LOL! I convinced my parents to outfit their new home with (store bought) LEDs and they all failed within a year. 99% of the time they overheat because the MFG skimps out on cooling. Either the driver or the emitter burn out, and TBH, it's usually the driver.
But once you get into LED specs that is where you find the good stuff. CRI being the big qualitative determinant. IIRC you can find offerings from CREE and Lumilux that are hitting 140 lumens/watt at 90 CRI. That should equate to lighting maybe 900ft2 for about 100W. This is off the top of my head so take it with an extra grain of salt. All said, good LEDs absolutely blow the doors off of everything. I could hand you a briefcase with high-end LEDS, heat sinks and all, that would light up your entire home for a couple hundred watts AND last for decades. Keep in mind, you can pick up a nice emitter that'll do 1k lumens at 10W for like 2$
If you ever want to revisit LEDs and give them another shot here is one of my current interests. Very affordable, size friendly for DIY, i.e. not too small, and a nice quality light output. Find a way to keep it cool and drive it and you will be a happy camper. Think of it like this, you could fit enough of these emitters in an Altoids tin to light your entire home and your neighbors homes on either side of you, for the next five generations, and the tin would still be mostly Altoids.
https://www.mouser.com/datasheet/2/602/DS164_luxeon_7070_datasheet-2585909.pdf
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I think the workaround here is you want to drive the emitters remotely. For example, a Meanewell CC driver that you wall up in an EMI shield and the emitters are fed by plain wire, no onboard drivers. You know better here, would the LEDs still radiate EMI? Not something I ever messed with. OTOH you can drive them with pure sexy DC voltage from a silky smooth Corinthian battery. IMO that's where LEDs really 'shine'. When the mains power goes out I just laugh and rub my hands together. Most things should be straight DC IMO. It's AC that's required for special uses. Even well bore-motors don't really need AC these days.
It’s true and I got that one electron trapped in my bug jar. I am going to trade it for bubblegum.
20W LED tube here starts $2, I find the spectrum wrong, use fluorescent most of the time.
Complete with ballast, ready to use 36W fluorescent (straight tube, not the folded ones) starts $3 here.
9W 900 lumen LED bulbs are about a dollar or so at supermarkets. Their failure is usually LED, the heat sinks are not enough for use over 4 hours, they seem to be improving as well from the early designs.
Tubes are softer in light, and higher lumens at 36W rated lamps (2400) than the replacement LED (1800-2000 at 20W), so the room is actually dimmer on LED lighting.
LED tubes seem to be improving now, very fast failure of driver due to bad design / ventilation was common, they use 80V rails on the LED strips.
Reliable drivers on panel lamps makes them a good option.
The tubes do reduce output over time, but they last a long time with proper electronic ballasts, magnetic ones need a starter, which gives a high voltage jolt through the filament every time you start it, reducing the life...and they hum at times.
PF of 0.55 is thought good for those magnetic ballasts, the actual watts consumed is nearer 70 than 36...electronic gear is usually 0.98 cos phi.
Complete with ballast, ready to use 36W fluorescent (straight tube, not the folded ones) starts $3 here.
9W 900 lumen LED bulbs are about a dollar or so at supermarkets. Their failure is usually LED, the heat sinks are not enough for use over 4 hours, they seem to be improving as well from the early designs.
Tubes are softer in light, and higher lumens at 36W rated lamps (2400) than the replacement LED (1800-2000 at 20W), so the room is actually dimmer on LED lighting.
LED tubes seem to be improving now, very fast failure of driver due to bad design / ventilation was common, they use 80V rails on the LED strips.
Reliable drivers on panel lamps makes them a good option.
The tubes do reduce output over time, but they last a long time with proper electronic ballasts, magnetic ones need a starter, which gives a high voltage jolt through the filament every time you start it, reducing the life...and they hum at times.
PF of 0.55 is thought good for those magnetic ballasts, the actual watts consumed is nearer 70 than 36...electronic gear is usually 0.98 cos phi.
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@NareshBrd can you do me a favor and shoot me some specs of your favorite tube? One thing I do not suffer from is 'oneItis', so if I find a better solution I use it. That said, if you purport some gain over whatever parameter, you have to consider the form factor and footprint/reliability/durability. I can't think of a single scenario where tubes to not have 1. The worst footprint and 2. The worst durability. Ever break tube? I know I have. If you fill the volume of a single tube with LED emitters you would have either enough lighting to provide hundreds of years of light for your personal living space or you could light up your local neighborhood for good while. I just don't see a way around this, the performance is so lopsided it would be a very, very tough sell. The emitter I linked in that data sheet is 1k lumens on a 7mm x 7mm footprint.
If you mean to say that once the light is evenly diffused, i.e. not a point source, that a tube has a higher output, OKAY FINE. you get some marginal gain via the losses accrued in diffusion of the point source of an LED. So is that your best case scenario? You have a ten percent gain of diffuse light over an LED at the drastic cost of literally every other metric; footprint, cost, durability, the list goes on.
You are mixing your power here. Do you mean that you get more light from 36W than you do from 20W? Well, I have to agree on that! "SOFTER" what is softer? Are you referring to color temperature? If you spec a 3000K tube as soft and I match you with a 2700K LED, Is the LED "softer" or is the tube "softer"? If you spec a tube at 95 CRI and I spec an LED at 98CRI is the tube closer to natural light or is the LED closer to natural light? Just a final thought on "softer" you are probably referring to the single point intensity versus diffusivity. That's a different problem, and I agree that there is a BIG difference. But we should consider what that difference is.
If you mean to say that once the light is evenly diffused, i.e. not a point source, that a tube has a higher output, OKAY FINE. you get some marginal gain via the losses accrued in diffusion of the point source of an LED. So is that your best case scenario? You have a ten percent gain of diffuse light over an LED at the drastic cost of literally every other metric; footprint, cost, durability, the list goes on.
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That seems counterproductive, first go through a lot of trouble to make efficient lamps and then waste energy by leaving them on continuously.
No disagreement there! I was literally testing failure mode for an off-grid product. You can only get spec in ultra high LED MTBF and I had to test my particular heat sink strategy. At a certain point, 5 year mark, I was like "Ok, these are good to go" lol
Somewhere around 2003, I was doing noise measurements of a long, medium and short wave car radio LNA at work and found that I had to turn off the fluorescent lighting to get rid of its interference. It was wideband interference, so you could not distinguish it from noise on the spectrum analyser. I don't know what ballasts were used, I guess electronic ones. The LNA test set-up had some wires of a few centimetres long connected straight to the LNA input.
There was an article about LED lamp efficiency and interference in Elektor some time ago. Some filament LED lamps came out quite good.
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Fluorescent tube?
There are two plants near my city, Philips (Signify now?) and Crompton.
Both have similar specifications: 2400 nominal lumens on 26 mm 36W tube, or same lumens on 40W 38 mm tube.
CRI I did not check, 6500K or so color temperature, cool daylight.
As the tube becomes smaller, the radiation intensity increases, and it becomes too bright, and the light becomes less diffused, and the life gets reduced...T5 lamp failure were due to heat damage on sockets, the tubes ran really hot, same case with the now obsolete CFL tubes.
Foot print on our tubes is just enough to support the tubes, so really not a big issue.
Reliability is the issue, I do not like having to replace lamp just like that, and that too in a dark room.
LED tube designs here are either a single row of emitters about 4 x 4 mm, or three rows of 2030 / 4040 emitters.
Either way, the heat issue (evening ambient of 45C is common here), means that the design must dump heat at that temperature, or (usually) fail. The failure rate was nearly 50% about two years back, so the sales are much lower than bulbs.
Some people used two bulbs about two feet apart, same light and more reliable than tubes!
I have 3 and 5 mm LED in my temple, and as decorative lamps in my house and factory, they have been running 24 x 7 in the temples for about 20 years now, so yes I know how reliable properly driven and heat sunk LEDs can be.
The issue with white LEDs are that the junction must be around 90C, so heat dissipation must be good. And they are sensitive to changes in supply voltage and current, so the driver must be good.
DIY, I can get Meanwell or similar supplies, mount say TV back panel LEDs, on a honking big heat sink, and get near infinite life.
It would look ugly, and so on.
For $2-3, not worth the hassle, so that is only for some decorative stuff.
In the picture, 40W fluorescent on left, 20W LED on right.
Not much difference in foot prints.
There are two plants near my city, Philips (Signify now?) and Crompton.
Both have similar specifications: 2400 nominal lumens on 26 mm 36W tube, or same lumens on 40W 38 mm tube.
CRI I did not check, 6500K or so color temperature, cool daylight.
As the tube becomes smaller, the radiation intensity increases, and it becomes too bright, and the light becomes less diffused, and the life gets reduced...T5 lamp failure were due to heat damage on sockets, the tubes ran really hot, same case with the now obsolete CFL tubes.
Foot print on our tubes is just enough to support the tubes, so really not a big issue.
Reliability is the issue, I do not like having to replace lamp just like that, and that too in a dark room.
LED tube designs here are either a single row of emitters about 4 x 4 mm, or three rows of 2030 / 4040 emitters.
Either way, the heat issue (evening ambient of 45C is common here), means that the design must dump heat at that temperature, or (usually) fail. The failure rate was nearly 50% about two years back, so the sales are much lower than bulbs.
Some people used two bulbs about two feet apart, same light and more reliable than tubes!
I have 3 and 5 mm LED in my temple, and as decorative lamps in my house and factory, they have been running 24 x 7 in the temples for about 20 years now, so yes I know how reliable properly driven and heat sunk LEDs can be.
The issue with white LEDs are that the junction must be around 90C, so heat dissipation must be good. And they are sensitive to changes in supply voltage and current, so the driver must be good.
DIY, I can get Meanwell or similar supplies, mount say TV back panel LEDs, on a honking big heat sink, and get near infinite life.
It would look ugly, and so on.
For $2-3, not worth the hassle, so that is only for some decorative stuff.
In the picture, 40W fluorescent on left, 20W LED on right.
Not much difference in foot prints.
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Bro, that is pure hell. Soft is so effing far from 6500k that that you would need industrial sapphire to plumb it through. Do you enjoy pure techno blue hues? The worst possible light you want is some high *** color temp. For a giant factory OK. In your kitchen, no way. In your bathroom fine. In your living room, absolutely not. You can't compare 6500K ( at probably crap CRI to boot) to 2500K at 90 CRI. You're trying to equate class B to class A in the lighting world. I stand to be corrected, but in that case give me the data sheet-
My dude, this is not good. Both are bunk. Sorry but you are comparing a crap fluorescent to a crap LED. Go find some pictures of high quality lighting and start figuring it out from there. What your photo depicts is about two steps above a little LED headlamp. And who wants to read a novel to a blue tinged 6500K headlamp?
Edit: and don't come at my with "muh cost." I just gave you a data sheet of emitters that would cost you about five USD to replace both lights in that photo. To the point that you would want to puke if you had to revert to the ones on that wall.
Look at these emitters that are tailored just to make fruit look good:
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I am not going to the trouble of building lights just to please you.
I use what is available, Philips is good enough for me.
You are entitled to your opinion.
I do trade in LED lights, I am a subscriber to some trade magazines.
So I know where we both stand in terms of knowledge.
No need to take it further, just accept that I can make better lights, just not in the mood tight now, I have other more important things to do.
I use what is available, Philips is good enough for me.
You are entitled to your opinion.
I do trade in LED lights, I am a subscriber to some trade magazines.
So I know where we both stand in terms of knowledge.
No need to take it further, just accept that I can make better lights, just not in the mood tight now, I have other more important things to do.