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Discussion Starter · #1 ·
The other day I experienced a loss of power to my LT150. The power came back on in a few seconds. The LT150 came back on, a short buzzing sound came from the projector and it gave some trouble codes matching the ones from a burnt out bulb. The bulb was off at this point, the codes flashing, and the fan in high speed. I left it alone so the fan would cool it off while I proceeded to freak out about the bulb being burnt out at only 60 hours of use. After the fan cut off, I left it alone for a few minutes, then unplugged it for a minute, and plugged it back in. It powered up normally and all seems fine. Has anyone experienced this? My power company is very reliable but these things happen from time to time. I could have lost a bulb there, or maybe worse! I think the buzzing may have been coming from an overheated bulb. Any input or similar experiences?
 

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The projector is made of plastic. When the power cuts off, the hot bulb heats up the precision optical assembly at the heart of the projector. Hopefully nothing is damaged when this happens, but there is that chance.


My guess is the buzzing was a rotating part, either a fan or a color wheel, distorted by the confined heat of the bulb, rubbing against something else. When it cooled down, it more or less returned to it's previous shape, and the buzzing ceased. Clearly this is something you do not want to do on a regular basis.


Two possible answers would be a UPS or a battery-powered external fan to cool down the projector - I built such into my hushbox.


Gary
 

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Discussion Starter · #3 ·
The sound was definitely not a warped plastic part. I am very familiar with electronics and the sound was clearly an electrical arcing sound. My guess is it was the ballast(or equivalent) circuitry trying to start an over heated bulb. Possibley a safety breaker or something. No optics are warped because the focus is as sharp as ever. Surely, the manufacturers would design an ability to handle this unavoidable occurance on a limited basis. And I doubt the color wheel is close the the bulb. I would think it more likely that it is after the DMD in the optical path. I guess I am lucky, it seems to be working perfectly, alhtought the bulb life may have been reduced, although I think it is better than the 1000 hour rating anyway. The LT150 must be rated so low because of heat buildup in the small case, and bulb bursts are better avoided. A UPS would be a good idea, but they are expensive.
 

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Shahram,


Once when I called tech support he told me that the light bulb was actuall covered under the warranty. He said that if it goes out before 6 months NO MATTER HOW MANY HOURS it will be replaced. i haven't checked the fine detail on my warranty card but you should check it out


Keep in touch


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David

Intel Pentium III 1GHz Processor 133MHz FSB

ASUS CUSL2-C ATX Motherboard with Intel i815E Chipset

Toshiba combo DVD CD-RW

ATI Radeon AGP 64 MB DDR VIVO

M-Audio Delta DiO 24/96 256MB PC133 SDRAM

60GB ATA/100 7200RPM (75GXP) IBM Deskstar Hard Drive

Windows ME

(made by Digital Connection)

And last but not least the infamous Dell LT 150
 

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I agree that a UPS for $100 is not unreasonable. My LT150 did the exact same thing though power was not out but a second or less towards the end of a VHS movie via Svideo. My VCR never shut off and the sound system was uninterupted. Power must have been flashed off and on quickly to cause LT150 to hickup like that. Of course LT150 image was shut off, funny smell gave off, and buzzed when it was plugged back in. Only a cold reset by unplugging would fix it. I'm sure it's hard on the bulb but what can you do. I'm gonna get a UPS unit to prevent this from happening. I notified NEC Tech. by toll-free number so they can log in computer. NEC tech had no idea why LT150 shut off while other equipment (VCR, stereo) was unphased. May be LT150 is a lot more sensitive. Anyways it's fine now but lord knows how many hours that episode took off this expensive bulb :-( Thus, $100 UPS may just be the ticket to let us powerdown unit appropriately and for fan to cool unit. External fan is a good idea too except for the additional noise :-(


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Huey ;-]
 

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There are relatively large capacitors to store energy in those other devices, especially the sound system. The LT-150 only weighs 3.5 pounds. I wonder how much of that is a capacitor? It makes sense that it cannot ride out a small blip in power supply as well as other equipment.


Doug
 

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Check this out for a UPS: www.directron.com/us1000.html

At 1000 VA, heck you can watch a whole movie on battery power :)


Even with $20 S+H, it's a great deal for 1000 VA. This may be overkill though :)

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Huey ;-]


[This message has been edited by Huey (edited 09-26-2001).]
 
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