Can we dooby Tesco's GU10 bulbs? - with schematic
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- เผยแพร่เมื่อ 6 ก.ย. 2024
- To dooby a bulb is when you reduce the power rating of an LED bulb to make it more efficient, cooler running and longer lasting. It's named after the infamous Dubai bulbs made by Philips for the Ruler of Dubai, who wanted the most efficient and longest lasting bulbs possible.
With modern linear regulator bulbs, all the main circuitry is usually on the LED PCB, making a slight modification easier.
This bulb was notable for not using much glue in its construction. The PCB was screwed in and the front lens was secured by a small dab of silicone at one side.
With some bulbs there's just a single resistor that makes them harder to hack than the ones with two in parallel, as the aluminium core PCBs are notoriously hard to solder on due to their fast heat dissipation. The easiest dooby is to check that two resistors are in parallel (they use two to allow finer tuning of the current), and then simply break one off completely, or crack the black top layer off.
In this case the power rating of the bulb started off at 3.5W and reduced to 1.2W with the 180 ohm resistor left in circuit, and 2.5W with the 82 ohm resistor left in circuit.
The intensity is reduced, but as LEDs are more efficient at lower power it still puts out plenty of light.
The 1.2W option would be ideal for an ambient light in the evenings or at night. It's power is so low that it could be left lit 24/7.
This task involves a device that operates at main voltage. The PCB should never be touched while the bulb is energised. The front lens should be fitted in normal use.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:- www.bigclive.c...
This also keeps the channel independent of TH-cam's algorithm quirks, allowing it to be a bit more dangerous and naughty.
#ElectronicsCreators
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I miss those "first LED lamps that last forever". I have two outside that go on every night with a dusk sensor, and they've been perfect for over twelve years running now, all night every night. Thanks for educating us how to replicate them.
I have a 3W LED lamp in my home that has been running for 15Y 24/7. No problems at all.
@@GeorgeZ213that's awesome. Like a Dubai lamp?
Got some early ones, that use 5mm LED's in them, and a capacitor dropper. Yes a whole 0.5W of light, but in the place it is in it is perfect. Lights up an exterior area that is small, and provides the right amount of light.
Mine fail from shit solder joints.
@@SeanBZA
The right amount of light in the right location..
Preferably without seeing the light source or it's difficult to see the direct light from the bulb.
I've seen room's in people's home's where the person has chosen not to have any lampshades and uses 200w filament bulb's hanging from the ceiling or in fillings.
They don't have any sight difficulties or obvious psychological condition.
A fun button on every piece of gear. Sounds like a plan.
Thanks Clive. Keep on breaking them down.
Exactly on both counts!
Word for the Clive Dictionary I'd missed: _"Deathbeam Capacitor"_
It's a reference to an idiot 5G conspiracy nut disassembling a streetlight, pointing to the mains (400V peak) capacitors and falsely claiming those produce the (imagined) death beams .
I'm sure someone tried explaining it to me once, but it didn't stick.
@@RaunienTheFirst 300v capacitor in led driver is used to power 5g death beam
Saving the world by breaking one SMD at a time, I’m all in. I only understood 50% of the tech chat but ❤ it 100%
@agustinusreynaldi7101 It won’t be long I am reading Charles Platt’s 📖
Tesco has always been near the forefront of lighting technology, in a way. Back when CFL bayonet bulbs were just getting big on the market (around 2005-2006) Tesco made really beautiful CFL glass-enveloped chandelier bulbs that were a breath of fresh air compared to the ugly 'loop' ones. They were cheap and reliable, I still have some on my main stair light.
The same thing happened with LEDs and they brought out cheap, stylish and powerful lamps when you either needed to get everything from an expensive specialist or import dodgy stuff from China (that were copies of the decent stuff). I still remember the Wharfedale DVD player they had that disrupted that market entirely!
I'm sitting here watching this video in a room with 4 of those very bulbs in a fitting on the ceiling. Two of them have died already after less than a year. I'll definitely do this to their replacements!
Just one dap of silicone in the corner to hold the lens on... they know what you're going to do to it anyway so they've given up and saved the extra silicone cost
Every little helps 😂
@@weehappypixie Comment of the thread 👍
The impression I get of Clive's house from these videos is it's cold, and dark - he keeps the furnace at 10C, and all the lights have been modified to only draw 1W or less
Having a cold house helps LED lamps to last longer. 🙂
I understood 'Erectifier' but I could not see a blue pill. Then it dawned on me that you said 'a rectifier'.
I am going to add that to the electronics dictionary!
I wonder what Google makes of my habit of searching for blue pill pinouts and so on, thankfully I haven't seen any ads yet
In my head it's "rectum fryer"
@@chrisglen-smith7662 AvE FTW....
@@chrisglen-smith7662 That is one of the early entries to the dictionary!
Those GU10 to BC22 adaptors are really useful for converting anglepoise lamps because GU10 spot plus adaptor weighs the same as an old incandescent spot so the lamp still balances.
After considerable experimentation, for everyday life illumination, 2700 k was determined to be most pleasant.(and similar to old-fashioned incandescent or indirect late afternoon sunlight.)
...2700k Pretty (literally) nice light color...I find the cold white lights that architects seem to prefer quite jarring...I wonder if any surveys have been done comparing productivity with light temp?...
@@leybraith3561 cold white light makes the room appear larger, more airy. Warm golden light brings the room perception in closer, more warm and familiar.
In photography, the late afternoon sunlight, the golden hour.
2700K is way too orange for me, and the 1800K are awful!
I like the yellow, much easier on the eyes and reminds me of many hours spent in HPS grow rooms.
It's been a bit of a rough day, so I'm questioning my life choices when I find myself genuinely crying with laughter when you "explained" what the FUN button was for. Thankyou good sir!
I remember first red led's I bought from Rapid Electronics, life expectancy was 27 years constantly lit, still have quite a few in the attic somewhere.
Gaz Yorkshire.
Those LEDs were the real 100,000 hour LEDs.
Ive been addicted to modifying led bulbs for the house since your modification video that came after the Dubai lamp video. Every time a normal led bulb burns out, I modify the replacement to half wattage. It hardly makes a difference to brightness, but they are certainly lasting longer, I havent had any of them fail so far.
Designed to fail ? Either that or down to the minimum price. I like how easily these come apart. With every failed LED bulb I have taken apart it has been a one way process. One just needed a new capacitor but by that point the case had several chunks out of it.
Like that valuable "fun" button on the An Tai device. For years I had a red keyboard button with "PANIC" moulded into it in white. Used to take it onsite at firms I worked for, and placed it on a gap in whatever keyboard I was using had in place. Endless entertainment! Liked the resistor delete mod for the lamps. Literally hacked it off, right in front of us all. 8^) Cheers!
I think An Tai sales are about to jump %1000 now that the secret about the FUN button is out.
Clive, you have topped it !! Of all the videos I have watched from you...but never seen:
The FUN button!
Love your humor and your videos!
I see a dooby video, i like a dooby video. Some say watching bigclive is like a gateway drug.
Please see my stand-alone comment.
Undisputed. Five years ago I understood ohms law and household electricity with some very basic electronics.
I now have a fully working bench set up with components & tools to Dubai, redesign, repair, create and experiment. My latest research is into Arduino and automation. My whole home is self sufficient for power with two central solar - battery systems and dozens of local point solar lights and pumps using reclaimed lithium cells and ultra reliable NiMH.
I spend hours tracing boards to figure out how they work, and collecting notebooks full of drawings and calculations. My inertnet searches are alldatasheet, alltransistors, WorldRadioHistory, AliX, ebay and more.
I've even reached a point of regret for boards I salvaged for components that now realise I could probably have saved.
All I need is hair restorer and a beard and a compulsion to carbonate beverages and I'm almost full clone.
What fun! Thanks Big Clive. Since you started showing the lower wattage modifications, I've preformed this numerous times with great results. It's awesome!
Oh, and the "Fun" button. LOL
I love that you keep throwing in the death beam capacitor references.
I ended up snorting my cup of tea when you explained the Fun button. Love it!! If it were true, I'd go buy an AnTai right now.
Just found this channel… not disappointed
You'll never be disappointed
He has another channel 'BigCliveLive' where he does livestreams 😉
Love how you include a succinct description summarizing the essence of all your videos. To their detriment 90% of youtubers omit this vital step.
I've had quite a few Tesco products and they appear to be quite decent quality; I've got a 10 year old fan from Tesco that still runs perfectly, very often in use. Motor runs smoothly, nothing falling apart
I don’t understand any of this video but enjoyed it all the same.
OMG... I LOVED your definition of the FUN button! There should be one of those for those spam phone callers, too!
R is a decimal point. learned something new.
Stands for radix. Fun fact
I bought a 1w led similar to the ones you modified over 15 years ago. As you say, the early ones last for ever. Still in daily use.
The early high power ones should also last quite well as they had large metal heatsinks.
Awesome - have repaired plenty by bridging the burnt out LED - I used to repair the HV inverter type and use them to drive small LOPT work pretty well
😎 I'm having my own Dooby right now 😎
5 years ago or so I replaced the halogen lights on my flexible track lighting system.. to the 3 volt led similar to what you're showing it just blows my mind that I can light my entire kitchen with just 15 watts.
just replaced nine 75W dimmable halogen ceiling GU10 for and old neighbour with the same number of 1.8W LEDs in one room and she dimms them by 50 or 60% now. that was the last part of the total LED and OLED replacement in her home. her next electricity bill for lighting should be around 1/30th of what it was before i started in late 2022. only problem is her cat won't be as comfy under the new lighting as he was with the halogen in the Winter... 😼
@@kittytrail I should have said three watt not 3-volt..😄
@@justsayen2024 my sm00thbrain _rectified_ it as i was reading it so no biggie. 😋👌
Nice. Thanks to you, I do this whenever I get new bulbs. Cheers Clive.
(although I think I've now replaced all my lights with modified bulbs, so I could be set for life)
Thank you Clive I will modify the hell out of it, I bought the little spotlight and it is good I will be using it for fishing off the back of my boat.
Clive, surely you can make a circuit that essentially operates that FUN button continuously to rid the world of lawyers.
I'm getting pretty annoyed by LED lighting. Colour temperature? Always a guess even if the packaging states it. CRI? Often still terrible. I have 2 huge Philips light bulbs with a twisted LED filament inside. They weren't cheap but bought a few months apart so from a different batch. They look totally different. The variables with LED are just too many. I long for the days where a bulb popped and you put in a new one which looked exactly the same as the previous one. It's become a big mess!
Stop buying shit bulbs, as problems described are prime indicator of shit bulbs.
Need to setup one of a machine that just presses that Fun button over and over forever.
Capacitive dropper is probably a viable dooby for these as well, assuming it doesn't put the regulator into disco mode. IIRC, with 240V/50Hz a 100nF capacitor would put you just shy of 2W. It's an easy enough thing to try without faffing around inside the lamp.
Every appliance should come with a Fun button
Thanks BigClive! We have a long light fitting over our dining table which takes six GU10 bulbs. The ones it came with it when we bought it 8 years ago are marked 350lm 2700K but are too bright. I immediately bought others, mostly from IKEA, starting with 160lm ones which were OK but only lasted a few years. I’m permanently on the lookout for GU10 LED lamps which are in the region of 200lm…..
Brilliant hack thanks Clive 😊
What do you call 1000 layers under the sea? A good start. Sorry, couldn't resist.
That was deep. Very, very deep.
Not too sure their maths works out, since I believe a 50W GU10 halogen is normally around 400 lumens, compared to their alleged 345, although perhaps the beam angle plays a part. Dunno how that works out. That said, I do like the idea of lower-powered downlights, especially if you can lower the power even further, since it makes them even more usable in "custom" applications. That said, if you don't fancy popping open your GU10 bulb and hacking it yourself, I noticed Philips offer a 2.4W model, which may be relevant to your interests. But you'll certainly pay for the privilege.
Having rented (in 2009) a "modernised" house fitted with halogen GU10s they seemed to use a lot of power while only illuminating the floor. I decided 350W of lighting in the hall was excessive and mainly used a 15W CFL fitted in a wall light which was adequate.
I usually seek out the 12v gu 10 bulbs as they can be easily rigged up and ran off a pc power supply with crude wiring without the risk of 240v pain, Also during a general power outage you can rig up a 12v battery in line with them and have light 🙂.
I need some gear with 'fun' buttons! What a facility! 👍😁
Interesting video 2x👍
Can you dooby the FUN button to make it target politicians?
As a law school grad, I'll say there's not enough hate for those that _hire_ lawyers. Even the most unethical lawyers only do what they do because some monster is paying them.
Not really, they are paying themselves. 💩
is there not hate for both :D
;) Just joking
Lawyers create work for each other and more back doors in the legal system making more business for lawyer then they go onto run the country without any understanding of humanity as demonstrated by the US Senate.
@@WOFFY-qc9teDon’t tell me *they’re* all ex-lawyers too. IIRC, Baby Bush (commonly known as dubya) bought his first degree with his name and then flunked law school with what the US call a ‘gentleman’s C’ - which I believe pretty much equates to ‘ya turned up’!
@@WOFFY-qc9te
Same in the UK.
...Ran across a $Australian29, 240v, 24 watt ceiling 'oyster' light (Casalux 380mm tricolorur from Aldi Australia) that uses a Maxic MT7714s driver chip.
...It uses a parallel set of 2.2&2.4 ohm resistors to set the LED current (designed for o/ps of 85 to 265v).
...Surprisingly low value resistors!
...Quite nicely built...very light (pun)
...Tried cutting out one of the resistors and it would hardly glow at all.
...Dropping in a 5ohm in parallel to the 2.2ohm produced a pleasant current reduction of about one third.
...Put a bit of heatsink compound under the LED boards and a chunk of heatsink rubber under the driver board.
...Lets see how long it lasts.
...Thanks for the ideas BC.
I wish I had my own big PINK handheld calculator.
Doobie in the states can refer to a single paper wrapped flammable self regulating while resinating THC delivery device.
And what does bogart mean? As in 'Don't bogart that joint?'
You realise it is actually a reference to Dubai who originally commissioned Ultra Efficient LED bulbs (as opposed to bright, hot running ones that burn out far faster than CFLs).
...Nice.. Wonder if any benefit would occur from leaving the resistors alone and applying a smear of thermal paste to the edges of the board?...
...Maybe adding some heatsink ribs to the outside of the case too?...
...Twould be a Long term project to test these possibilities...
...Probably more beneficial in hotter countries?...
This doesn't just make the lamps cooler, it also reduces the Watts of electricity to purchase from the power company for each 1000 lumen of light output, because the LED chips are more efficient at the lower current level .
Thanks Clive.
That FUN button should be on many devices!
"The fun button: every time you press it, a lawyer explodes somewhere in the world. I have to control myself or else I'd just press it all the time." I didn't know this was one of the things they taught in an electrician's apprenticeship! Is there a similar button for politicians?
Like the Staples button, "That Was Easy" 😅
🤞
When Clive plugged the bulb into Anne Adapter I was expecting him to get a slap to the beard. Ref BBC comedy show radio active from the 80s
GU10 bulbs are the bane of my existence, One always seems to die right after changing another in my kitchen fixture 😭
LEDs? You may have electrical fault because all the ones I have have lasted for years.
How strange; none of the GU10 LED bulbs from different suppliers have gone wrong in years, and I have bought them from different sources - IKEA, Screwfix etc; I have only swapped to replace them with brighter units (also, the older ones used to take half a second to turn on).
You just keep pressing that 'FUN" button Clive, and lawyers be damned!
Very damned!
Why not replace both resistors with a small potentiometer and then you could select the wattage of your bulb
Viable but it would need to be in series with a minimum value.
The advantage of this technique is that it's free and easy using commodity bulbs and requiring no parts, no soldering, and no skill. If you're going to go to the effort of soldering and rewiring it into a DIY dimmable bulb, that sounds like a cool project and more power to you but it's probably not useful in large numbers and that's not what the point of this is. Dimmable bulbs are already available. The point of this is to make a cheap bulb that will fail rapidly into a cheap bulb that lasts almost forever while being free and easy.
@@cecilkorik I'm aware
8:45 I've got a mad idea about a Legal Eagle collab 😬
Yay, dooby again. 👍
Well presented Sir Clive.
I use the globe (translucent ball) from a failed regular LED lamp to replace the 'lens' from a G10 lamp, (bit of silicone adhesive helps) and the same adapter you have here, to replace the original globe lamp. I found lots of packs of ten 'branded'* G10 5W LED bulbs for £1 a while back, so my lamps cost me 10p!!! (From Philip or Weeks 🤣if you know what I mean*).
All resistors are fusible. It just depends
Great video Clive! Always nice when you release a new dooby one, hopefully saves power (and money) for a lot of people ^^
But I find that adapter you used quite doobious... The exposed metal part that's still in finger reach even when it's plugged in doesn't look safe... But should be an easy fix with a piece of electrical tape or similar.
Another great video! A rough idea of the efficiency would have been nice, even just using the built in light meter in a smartphone could suffice for giving an idea of the relative change of the light output, to see if the efficiency improved significantly.
That calculator is delightful!
A brilliant video Clive. (although a little less brilliant after the dooby) keep pushing that bloody button, you know it makes sense!
I'm surprised you didn't get a strike for pressing the Fun button!
Mr Lesco will come round and knuckle you Clive for this Dooby on his lamps
Thank you for the break down
*OLYMPICS*
Thanks Clive. I'll keep an eye Out Down here In case they turn Up.
On my screen, it just made your bench brighter, that Off, near orange colour.
There is an interesting design change here from other LED lamps that I am not sure is fully realized. Pausing to notice the lamp’s lens is part of it. In most if not all the LED lamps you have shown us the LEDs are distributed throughout the metal backplane. Wiring that up and the supporting components drives certain construction parameters. This new lamp is different. The LEDs are concentrated in the center and the internal reflecting lamp lens takes care of distributing the light, perhaps to a better result than the LEDs all over the place design. That must have a circuiting benefit. Being able to manufacture that special internal reflecting lens with quality at a low cost is something new. Lenses like that almost clear hunk of crystal plastic was demonstrated 10 years or so ago in lighting industry magazines as things to come. I guess the time has come. We should be seeing all sorts of novel ways of using these light bending lenses.
4:39
Those resistor's...
Fade would be nice.. switching on and off.
The ghost glow...
Is this FREE rather dim lighting?
Idea for night lighting in a hallway.
Have several if not bright enough..
A FREE light video?
Or is that illegal 😻
I'm Off-Grid.. for 36 years.. 12v .. solar, wind and generator 2 stroke 600w with a good 7 stage battery charger. I'm about to upgrade to a MPPT charge controller with staged charging.
Have you seen the 12v LEDs .. the various places sell..
I bought 2 a couple of years ago, they are great..
Are there any modifications, if so maybe make a video.
I mainly use filament bulbs 2.2w .. mainly as I like the light they produce and use little power.. the screw in type used in older car dashboards.
Great video. Would love to see some teardowns and hacks of IKEA lights some time!
I've looked at some IKEA lamps.
I bought the 8th generation of Hopi. And I did not get that FUN button!
That was dubious.
I know it is a bit a wild idea, but you could use a soldering station to remove the resistor ;-)
They use 2 resistors. The total value was also possible and also cheaper with one, so there could be a reason they used 2. I would measure the voltage over both and calculate the power, it could be to high for one. If so you could replace it by a melf version (edit the datasheet states 1V on the RS pin.) That 30 ohm is not dropping 240V. It drops 30 times the current through it.
The PCB is aluminium cored. It sucks heat away from a standard iron.
I'm always amazed how gu10 cram in the Cray computers to run a few leds yet floodlights with a surface area of the amazon use a couple of scorched chips, rectifier and a resistor to run strings of leds
I bought an LED "corn" lamp recently marked 80 watts.. I figured it was probably about 8 watts and it was the equivalence. The box does show pictures of warehouses and shops etc.. well it's actually 80 watts and bright as the sun... apanarantly a direct replacement for metal halide lamps. puts out a heck of a lot of heat too.. best part is all the hundreds of led chips all over it are all exposed.
It probably has a lifetime of about eighty days 🙂
Great video thankyou for the upload
I have two soldering irons in my lab to take these things off :)
I would replace the FUN button with a solder bridge.
Clive's going to be kidnapped by a Dubai Prince and forced to spend the rest of his days modifying lightbulbs
These hacking videos remind me of when I first got my most recent TV. I was initially a bit shocked to find its power consumption topping 150W from the mains, and the factory setting of the backlight was full blast, which was insanely bright. Cranking the brightness down to 20% cut the power usage to a more reasonable 25-30W and made for a display that was still plenty bright enough for comfortable viewing both day and night, without burning my eyes.
When I think about it, that's over 100W of power spent on LEDs inside a little 55-or-so-inch-across enclosure, which is far more than many people use to light their whole living room. A bit overkill? 🙂
And yes, even 50% brightness cuts the power consumption for the backlight in half while still visually appearing more or less just as blinding as 100%, as far as I can tell.
Modern LCD TVs are always supplied set to absolutely maximum brightness to destroy the LEDs as fast as possible. Just like the LED bulbs.
I had a few GU10 bulbs which lost the glass spontaneously on its own. Might explain that they were secured only half
"dooby" ... i think that means something different in the rest of the world!
It's actually Dubai, the rich emirate that did an exclusive deal to get higher efficiency longer lasting LED bulbs than other countries from one of the big factories . Those better bulbs were named "The Dubai Lamp" on the packaging . So Clive uses "Dubai" as a verb to mean improving a normal quality bulb to approximate the Dubai Lamp efficiency and longevity, usually by changing the part that determines how much current is pushed through the LEDs inside .
@@johndododoe1411 r/woosh ..i did read Clives description....
@@johndododoe1411 Now available in other countries as Philips Ultra efficient. I just looked and their 50W equivalent GU10 takes 2.4W. They cost about ten times the price of these though.
Nice 'lamp hacking' video! Any chance you could show a mod which would give a fade up and fade down over 2-3 seconds. It could be popular, and is easier on the eye that a harsh on/off. Cheers!
Don't be a "Don't Bee",
Do be a "Do Bee".
Would it be possible to pop all your Dooby vids, including the original Philips vids, in to a playlist please?
Interesting lights - I wonder if they would consider adding another 12 chip LED array which would give a voltage of 324V - still just under the 338V from 240V mains - instead of 288V to drop less voltage across the linear regulator - although depending on the UK's minimum allowed mains voltage, that may be too high....
Some bulbs do have multiple optional LED positions for fine tuning of the voltage.
Where I live "dooby" is a slang noun meaning a "spliff" or "joint", ie a DIY cigarette rolled by hand usually containing marijuana.
Indeed it is where I live too.
So, are BigClive and Ralfy the dooby brothers?
Today the Isle of Man, tomorrow , the world!
Interesting. I would like to do that. If I had those lamps.
even now in the united states we are seeing led bulbs ghost glow mostly the cheap bulbs that the utilities hand out for free to encourage energy savings.
i am on a program for low income called on track where the power company will forgive the difference in cost if i pay on time and they gave a 3 pack of leds and one of them ghost glowed.
you really only notice it on single bulb fixtures because you have the parallel load of the other bulbs in multi bulb fixtures with the exception of fixtures with 3 way lighting where each click of the switch changes a combination of 2 or more bulbs in a binary counting kind of way.
also by having that resistor across the capacitor it discharges the capacitor as people in handling the bulb may come in contact with the connections on the base and depending on how many diodes used in the ac to dc conversion network some leakage may happen and a shock could happen.
it is still good to put up a disclaimer especially on really dangerous deadly stuff like microwave transformers that can easily put out over 2000 volts at 500 ma witch can be over 1000 watts.
On the subject of light bulbs….I’ve always wondered (but can’t be arsed to try it) what would happen if you put two, three or four of those auto sensor night lights next to each other.
Doobying them to work on a 12v car battery for camping would be good? 👍🏻
You can buy 12V LED lamps already. Usually made for RVs / Caravans. I like the "paddle" style ones rather than those that attempt to mimic a bulb.
Mains voltage, yum yum.
enlightening .... big man
Clive...........😢
I made a bit of a boo boo and I bought the 2.4 Watts equivalent 35 watt.....
Which I'm not entirely sure how to hack as the circuit board circuitry is slightly different layout with those two resistors appear to be in series......
As an amateur I could be wrong of course....
On the plus side I picked up a box of 6 & only got charged for a box of 3......
Please would you do a video on the 2.4 Watt 35 watt equivalent.....😊
P.S. Clive........
Thank you for taking the time to read the comments, despite your busy schedule at the Edinburgh tattoo.
🤩
I wish the "fun" button would magically make cartel offices useful.
These look identical to the Energiser brand ones I bought in a local discount store. Same wattage, same lens. £3.99 each for dimmable, £2.99 each for non dimmable. I would suspect Tesco ones are cheaper.
I have been using them unmodified for around 18 months, seem to be ok and have the colour I prefer (2700K).
Just the job for sticking into some certin GU10 PAR16 cans, well, assuming someone wanted sickly yellow light coming from their lights of course... :P