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How could you hack an incandescent light bulb to last longer? Answered

I found a youtube video (can't find it now) that showed how to attach a silicon diode to the cap of a bulb before inserting into the socket. Apparently this reduces the power so the filament burns cooler and lasts for several years in constant use. However the video wasn't very clear, especially for someone like me who knows little about electronics.

Could someone do a fool-proof hack instructable? There was also mention of a commercial version which I can't find anywhere. It was a diode-cap combo that you place between the bulb cap and the socket.

Or are there any other ideas?

It would be timely with all the health concerns over CFLs and the imminent  lack of availability of incandescents!

With thanks.



3 years ago

Try this very simple circuit.

When a diode is conducting the bulb off and the other lamp is ON.


Thanks so much for the contribution. Same response as for Hristov really. I've flagged you both while I work on this. I could be gone some time! :)

Here is what I try to explain in that schematic


Thanks so much for taking the time to to do this. I don't speak 'schematics' so I'd better go and learn and I'll take this away with me. I love your name, btw. You sound like you should be in a novel. ;)

Hello to all of you who likes the warm, noiseless incandescent light. You can make the bulb last a lifetime with the following arrangement. Use 2 bulbs of 100W and 2 diodes 10A/1000v (10A10) and some wires. Supply the positive part of the AC phase by using one of the diode for the one bulb, and with other diode connected in the opposite way supply the negative phase of the AC cycle to the other bulb. Also both bulb must be close to each other in the fixture. By this flickering will be reduced almost to zero and the filament will run colder and life span will be hundreds of years. You will forget when you replaced for the last time the bulb, so put a metal plate in the fixture engraved with the date of placing the bulbs for the next generations.

Thanks for this. Any chance you (or anyone reading) could do a simple instructable with pics? I can't quite visualize what you're describing.

I found the original youtube video:

Wouldn't it be easier with a lamp to adjust it at the plug? Anyone know how to do this?

It's flawless and remarkable what we try to succeed in here, against all odds and corrupted government. The programmed obsolescence within a 1000h of life can be changed. This second schematic of wiring of the bulbs and diodes does the same job and will make the same reduction of the average power shown in the photos down. Only have to take in mind that there are no eternally faultless elements. Especially diodes. If one of the diode go out of order- normally it melts and make short-circuit. Via this low resistance on the next half cycle other diode will close the main voltage and all the current will pass through the both diodes ending with explosion. Also do not use 1N4007 especially here in Europe at 230v. It breaks very easy. Use 10A10 - it can handle 10A current. normally when cold the bulb have 10 times lower resistance when it's hot, so for 100W bulb normal current its about 340mA , and when ignited 3-4A. All High Voltage work must be carried out by experienced persons, shock from mains can be lethal.

In conclusion in wiki is stated that lifetime is approximately proportional to V −16

So in my calculations reduction of the Voltage from 227v to 159v, and normal life of 1000h will increase the life of the bulb to 367529hours or 42years. Correct me if I'm wrong. Be safe to all.


Dimming any bulb makes it last longer. The health effects of CFLs are nothing compared to the health effects of mining coal and burning it.


Bulb life goes up as the third power of reduced voltage.

+1 as well

If we all dispose of CFLs correctly and don't eat them, then I think the health concerns are basically nil. Personally, I love CFLs, and still have one that is five years old and has survived three apartments and two storage units.

That being said, when I do use incandescent bulbs I always just put one bulb in the fixture instead of filling it all the way up. I save on electricity and bulbs that way.

I hate to be the one to tell you this, but... just like Roy Batty, filament style light bulbs were not designed with longevity in mind.

In fact this is the result of a vast conspiracy on the part of light bulb manufacturers to intentionally limit the life span to 1000 hours or less, as revealed in a documentary titled "The Lightbulb Conspiracy"

According to this film, light bulbs were one of the first products to be re-engineered to make them fail more quickly, and this idea of planned obsolescence spread to numerous other products, like um, almost everything!  The film also examines printers that self-break after counting a set number of pages, Ipod(r)s with batteries that die after 18 months, etc.

Right.  But like Roy Batty, you WANT MORE LIFE, for your light bulbs that is.

Putting a diode in series with your filament might work.  It would definitely make the filament colder, and dimmer. 

Leavingt the bulb on all the time will lengthen its life as the shock of heating up and cooling down is when they break.

The diode will cut off half the AC supply (that half of the cycle where the current is "going the other way".

Think of it as a crude form of PWM, effectively switching the bulb off and on sixty times a second, which would let the bulb run cooler, but also much dimmer (the hotter a filament gets, the brighter it gets, that is how filament bulbs work). I'd worry that the rapid switching cycle might actually stress the filament, shortening the bulb's life. You'd have to test a number of bulbs over several years to check.

So, you'd have to get a diode capable of running at 120V, and you would also have to have twice as many bulbs running to get your room up to the same brightness as you started.