I have had an InFocus LP120 projector for just over a yar and the lamp has burned out. I've tried twice with two different companies to order a new lamp. Each time I received an email a few weeks later stating that they could not fill my order. (Most likely out of stock.)

In the interest of science and saving money, I've decided to try making my own replacement lamp. I went to Home Depot and bought a 120v 100W Philips Halogen bulb. Everything fits together fine, the bulb is set up to run off of the projector's power supply. When I press the power button on the projector, the lamp lights and slowly gets brighter as the countdown from 10 progresses. However, when the timer reaches 7, the bulb turns off and the LCD on top of the unit reads "Retrying...Wait". It does this five times and then tells me that the "Lamp would not strike."

I assume that I am using the wrong bulb type, voltage, or wattage. Does anyone have any ideas as to what I'm doing wrong?

Thanks in advance,
Skylar

[beecee]

try reading this thread, might answer your question...

BENQ Bulb burned out, can it be hacked?

Thanks, that did answer my question. It appears that it can't be done...cheaply.

It would be extremely difficult to find a place to buy the correct bulb, and even if I managed to find it, I would still be paying just as much for it.

[throwit]

hi LiqdPlumr

i'm really interested that you got this far...did the bulb you used require a startup power supply (did you use all three wires), or did it require you to trace the two appropriate wires to supply the bulb you bought ?...if so , your projector may not be working because it needs the startup to be simulated

have a read of this... to all projector owners...anyone made an led lamp yet ? done some research, need help ...i've been looking into an led lamp for much the same reasons as yours

The bulb that I used required no high starting voltage and, surprisingly, it doesn't hurt the bulb. Actually, my projector only has two wires for the bulb. It sends a high voltage pulse through these two wires to strike the bulb (I found this out after frying my 1kv multimeter.)

I have simulated the startup with a large 8W 100Ohm resistor. The projector was actually tricked into thinking there was a bulb there. The only problem was that when I looked at the resistor (this thing is a monster) it was glowing red hot. It actually melted a pretty good sized hole into the countertop without even contacting it.

This shows that fooling the projector can be done, we just need a safer way.

And my halogen light will actually turn on to full power, providing about 1900 lumens...the same amount of light as the stock lamp gave off.

I think an LED lamp would be very possible, though pretty expensive up front. Excellent idea.

[throwit]

thanks...you're braver than i !...although i desperately want to make this work, i've had my fair share of electric shocks from bad house wiring (not my own !) and consequently i have been happier typing about this than actually doing it

do you know about programmable microprocessor controllers as suggested by rjp996 ? i have not the slightest clue how these work, but maybe you do ?

perhaps we could pool your knowledge and my tiny brain and get our lamps going ? - if you can help with fooling the circuit i'd be very happy to help/share any info etc i can

I think that it is possible to get these things working. It'll just take lots of time and lots of thinking. My goal is to get this done before Super Bowl sunday...but that's probably not gonna happen

Yes, I do know about microprocessors. I have a whole collection of them and have used them on many-a-project.

I'm still brainstorming safe ways to trick the detection circuits.

I just discovered a patent for a lamp control system. It could be very helpful in figuring this thing out:
http://www.freepatentsonline.com/6891338.pdf

Also, I found a whole page of InFocus patents to sort through:
http://www.freepatentsonline.com/sea...=on&sort=chron

this is all rather fascinating... my projector (Plus HE3200) also has a 130W UHP bulb, which now costs more, at over £300, than the projector's worth. Would be cheaper to buy a similar spec projector with a 2000-3000h lamp life, and chuck my projector out altogether. such a waste.

anyway, cool project I look forward to hearing how you get on...

I'm surprised the hi voltage at startup did not blow your halogen bulb. This is news to me, I would have thought that would have just obliterated the filament instantly. You actually were able to get an image to project out of the lens though? I see someone referred you to the other thread so I won't repeat my lengthy post here but in a nutshell I had just connected directly to the back of the 110v poeer plug to toally bypass the ballast circuit, and just light the bulb, but I got no image whatsoever out the lens. WHen I looked up lumen diffrences I found there to be quite a diffrence, for a 150 watt hal at only 2900 lumens a 150 watt UHP was about 14000 lumens. What wattage was your original bulb, if it only put out 2900 lumens it couldn't have been much over like 50 watts, being an arc lamp? I'm kinda confused by that spec. Where did you find the original only putout 2900 lum? You can't go by the ANSI spec on the pj as that lumen output is after its already been through the optics and the actual output of the lamp itself will be much higher. I too am interested in this "fooling circuitry" perhaps mine would have put out a dim image if the DLP chip would initialize?? I'd be satisifed with a dim image even on that old Zenith if even just for testing purposes, but I couldn't get squat to project w/ my 150 watt hal.

**addendum** I couldn't help but chuckle at the statement " I found that out when I fryed my 1kv voltmeter". Please note I'm not laughing because you fried the meter, I been there done that with many other electronics (fryed them doing something stupid and then being p**sed at myself for awhile over it) but at the gross difference between the rating of that meter and what actually is used for startup spike, most PJs pop at least 15 kv to strike the arc. Have you simply tried shorting the 2 HV leads together? From what I understand I think some PJs may just sense the "complete circuit" once the arc is struck...since before it is struck the bulb is technically "open" as in its an open circuit. I often thought about trying that, just shorting the 2 leads together but was afraid to, as I'm not positive that'd be all the PJ would look for was a completed circuit thru the bulb. However please do not try this on my suggestion alone, I woudln't want to feel responsible if it blew out something in the PJ. I just wondered if perhaps you had already tried it and it didn't work.

[throwit]

is that correct...150 watt uhp equals 14,000 lumens ?? i know that some brightness goes passing all the cogs and wheels but that is hugely bright !...if a 150 watt uhp gives off that much light i'll have to change my led lamp plans quite a bit ! pleeaaase tell me this was a typo !

I will try and find where I read the article about arc lamp efficacy and post it, I may be remembering wrong but I don't think I am. I too was taken aback at 1st by the large diffrence.

Until I figure this out (or someone else), I found a site where you can buy the exact stock bulb that you need: http://www.myprojectorlamps.com/

For my projector, I would save about $200 buying just the bulb and not the whole lamp assembly.

[throwit]

scarier and scarier !

so, although as you say, not one to try for larks, it may be possible to join the startup circuit together (IF one KNOWS what one is doing), would this be all that was necessary to do the fooling i wonder ?

that's the darn difficult bit...if we can overcome that, you could light your projector with just about anything...even a solar collector ! (in the day anyway)

I was thinking about directly shorting the power leads but I am still not sure if this is safe, or if it will work without frying the control circuitry.

I'm very tempted to try it but if I fry my projector, I'm totally defeating my purpose of trying to spend less money

The first step to finding out what type of light sources will work in a projector is to find out what kind of bulb was originally in it.

On the side of my burned-out bulb it says Hg (The symbol for mercury). My guess is that the lamp InFocus uses is a Metal Halide lamp. If this is true, it would mean that my old 132w lamp gave off 14250 lumens when fully lit. My dinky 1900 lumen halogen would barely give a very dark picture.

Does anyone know for sure what type of lamp most projectors use?

By the way, I found a site with a graph comparing the luminous efficacy of various lamp types: http://www.lamptech.co.uk/Documents/...troduction.htm

[throwit]

this sounds like awful news. but...my lp240 does have what looks like a really chunky slab of reddish purple plastic immediately in front of the lens, which i believe to be a colour correction filter, if there are one (or more) of these, and if they were to be removed, then perhaps that might go some way towards compensating for a feeble 1280 lumen led lamp

similarly, if the polarizers were to be adjusted, then it could still work

Yeah, it appears that if we want to use our "wimpy" light sources, we're gonna need to do some physical modding to the projector itself. However, it may still be possible to build an external setup based on a cheaper but larger metal halide lamp. A high pressure sodium lamp may also be a possibility: http://www.socorroelectric.com/rateSEC.htm

Currently, we have 4 options for fooling the control circuits:

*Directly shorting the power leads together - Risky. Might work but would use a lot of power. Some sort of control system involving a relay might be required.

*Using a resistor - Dangerous...though I have tested it and it works. The resistor would get very hot, and would be gigantic. It must be external.

*Directly tapping into the control circuitry - The control board could be fed the signals that it wants via small microprocessor. Gurateed to work, but highly complicated.

*Using a similar but cheaper bulb that uses the same ignition method as the original lamp.

[throwit]

it's not beng precious, but i'm still keen on the led idea if workable, as if i'm honest i couldn't even afford the projector which is still a part of my visa balance ...i can either buy an off the shelf lamp, or if we can make this happen, then i can halve my electricity bill and get 10,000 to 20,000 hours from led. and although i make extensive daytime use of my projector, i can live with a dimmish picture especially if there is a side benefit of greater contrast at night

the final bonus for me is the possibilty that the projector will last far longer without deterioration - the lamp could last 2 to 3 years and the projector maybe a decade, by which time not only will led be all over the market, but i'll actually be able to afford that replacement !

So you did find the lumen chart...and yours was about 14k lumens too, I thought so. THe metal halide lamps are very very bright. That was my main reason for giving up on it, once I found out that info I figured nothing would work, I too considered LEDs but figured no way in he** are they gonna work if we need that kinda lumen output. Also considered an HPS lamp (as I have a 150 watt right now too) but figured the orangeish color of that would so mess up the pic it wouldn't be worth smashing even a $28 bulb and trying to rig the arc tube into the PJ somehow only to find out if it does light ok the PQ is horrible cuz of the orange color of HPS.

[throwit]

possible (though rather clunky and basic) solution to lamp simulation...

okay, here's a thought...extend the wires out from the lamp housing in the projector, have the original lamp in a custom airtight housing somewhere close by...but instead of it being operated and illuminated in the usual way, perhaps it could start up as usual (the hardest part to simulate), but in place of the normal running of the lamp, a resistor could be wired in at the lamp (assuming that used in this way, the resistor will not get very hot/use much power) to replicate it running normally

then the previous info regarding an led lamp could be applied to lighting up the picture

on the same topic, maybe the uhp lamp to be rigged in this way could be sent off to a relamping company and have the pressurised vessel removed to make it (i guess) safer but no replacement installed - would the arc gap still work in a normal room atmosphere

i know this is all pretty crazy talk, but ideas like this can explode outward (hopefully the lamp won't ) and later contract down to something more sensible

*i've posted this anywhere there are related topics so please don't get annoyed if you've read this before or do again !

greetings all.
i`m also interested in trying to `trick` an Infocus LP540
but my electronics knowledge is Zero.

have you guys read this thread,
ragedemon has cracked it after a long time tryin.
he also offers his email addy for assistance.
http://www.stereo3d.com/discus/messa...tml?1080477918

[throwit]

thanks Codepuncher !...i'll have a look at that right away

[throwit]

seems to know what he's doing doesn't he ?

i put up a post asking his advice, if no reply i'll email him in a few days

yes a very knowledgeable bloke.

looks like you got a result from your post, may be able to get him
through the other forum for a direct chat as well. very friendly.

let us know how you get on please throwit.

[throwit]

no real progress as yet...i'll follow up when i have more...i'm going to post on the other forum he frequents and prefers

as you will know from reading at stereo3d.com, he got the job done with use of resistors, but i'm a little concerned and depressed that these may be the only way to go, as the mention of great heat radiation suggests to me that there will be little or no energy use reduction, that would be a shame

its one of those real annoyances that the right person (myself excluded) could SO EASILY rewrite the firmware on any of these projectors to make them speed up or slow down the fans, run without a bulb or many other tweaks, but this theoretically simple move is effectively impossible

i'll keep digging

[throwit]

got a reply from RAGEdemon, he's encouraging, especially seeing as how he's done it...haven't coaxed him to here, but when i've got something together to ask him, i'll get back to him with questions

just a quickish update (same as at "to all projector owners...")

well, i sent this to the maker hkje (ebay)...

hello...i have (with others) been researching leds to replace the uhp lamps in projectors...we require dimmable, mains powered led lamp clusters, if you're interested...the common factor is that the space in the lamp housing of basically all uhp lamped projectors is 45mm x 45mm x 45mm (square), and the brightness requirement is in a range from approx 500 to 5000 lumens...although this may be beyond the current capabilities of led technology, the closer you can get to this ideal, the more potential customers you will have...incidentally, the high lumen number i have stated is most likely only as a result of filters/polarizers fitted into projectors, which could be removed, giving (i estimate) a maximum requirement of 1500 lumens...this may appear to be a restricted market i am asking you to develop product for, but think of the general lighting market - the potential for sales of compact lamps this size is huge (desklamps etc) - i would be happy to answer any questions...regards, matt

...lets see if anything comes of it

i was writing about this lamp business elsewhere, and it occured to me upon reading about the mitsu pocket pj (http://www.bigscreenforums.com/forum...572%26page%3D2 - 40 lumens output ! or possibly 120 lumens output - if 40 each of three leds) that the real problem here after the phoney lamp use bit, must be neutral filters and polarizers...if and when i get brave enough to do this thing (post warranty - still some months away) it would be wise to try with either no neutral filters/polarizers in place at all, or if adjustable, polarizers tuned down to minimum filtration

i'm going to contact luxeon/futurelectronics again with a similar message to the above

[throwit]

yet another barmy idea

i know it's not much good, but i wanted to see what any interested parties thought (this thing is getting complicated to say the least, but it's just another thought for the pot)...

you know when people have solar panels and put the juice into the national electricity grid...well i was thinking that maybe (assuming cost/complication are small, which they probably wouldn't be) a similar setup could be used...the projector would have a sparkgap for initial load, then in place of a resistor, the juice could be recycled back into the mains circuit (after being converted to compatible output)...assuming that the projector could be fooled in this way, then it is a possibility - of a sort

and there's now a sister thread at stereovision.net...(where RAGEdemon resides - he's got way further than me !) http://forums.stereovision.net/viewt...2467&forum=4&2

(same applies - this has been posted in my other signature links)

sorry i`m a bit thick and cant add to the technical aspects of this thread


Here`s another discussion on using LED`s
http://www.diyaudio.com/forums/showt...threadid=75568

[throwit]

Codepuncher

there are many kinds of smart, and many more varieties of stupid, i'm sure you haven't done half the completely moronic things i have, and good for you if you haven't (just for the record, i'd like to advise anyone who cares to know, that time is precious, women can be huge liars, as well as totally two faced and insane, the right person is hard to find, life is short, and if something is genuinely good or right, don't ever forget it or let it go as long as it stays good or right) i could go on but never mind

you have been an immense help to me and anyone else who is trying to figure this out, that cannot be overestimated i had no idea about this other forum and the many intriging links contained therein, i'm gonna do some digging there

i'm sure you didn't really mean your comment - but don't think that way - okay ?...knowing a little about stuff, i'm sure that you have many insights more to share, so don't stop

by the way, did you mean adding here, or there /\ ?