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Old 28th December, 2004, 09:35 PM
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Chernobyl Chernobyl is offline
Projector Wizard
Join Date: November 2004
Location: UK
Posts: 594

Originally Posted by gizmo
You can blow air directly on the bulb to help cool it and extend the bulb life, but you have to be very, VERY careful. Reason being, as hot as that glass envelope gets, you can create enough of a temperature differential to shatter the bulb. This means that great care must be taken in ensuring that you have even airflow across all of the bulb. As this is very hard to ensure, most of the less expensive designs don't even try.
Great stuff!
At some point I'll put a slow little fan inside the OHP in the vain hope of moving more heat from the bulb, extending bulb life.

My first bulb died after about 2 weeks of (ab)use! I did expect this, but at least we can gauge a little, how much powering up/down the bulb can affect its life. It was switched on/off 10+ times a day with many changes between low/high power. I cant say how many hours it was used, maybe 1/2 its rated life for high power?
In theory on the low power setting it will last up to 270 hrs.

For a real one shot innacurate measurement of switching vs lamp life, it will last 270hrs or around 140 switches.
This equates to around 2 hours per switch on. If you use it for less than 2 hours each time you power it up, you will lose lamp life.

Thats real rough and shoddy but I have to start somewhere
2.9m DIY home made LCD PC projector !
Venice 3000+ (1.8GHz) @ 2.7GHz, 1.4V
Stock air cooler
X1800XT clocked to PE
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