Groups

    Tricking an Infocus LP-340B Projector into thinking there is a bulb installed?

    Hia there,

    I have an InFocus LP-340B projector which has no bulb and I do not plan on buying a new bulb.

    My question is, does anybody know how trick it into thinking there is a bulb plugged in, so that a bulb could be DIY'ed in... - basically so that the projector will power up and display the Infocus logo with the help of a light source.

    Also the bulb plugs in via a 2 pin connector thing.....

    Tim

    21 Comments

    Banned

    The trick is.....
    buy a bulb

    Banned

    it seems projector bulbs are the new inkjet ink

    made to be as awkward and expensive as possible

    Original Poster

    ryman1000;8029009

    The trick is.....buy a bulb



    At the price of a bulb and for a projector of this age there would really be no point.

    As it is relitevly old I would think the method of bulb detection would be relitively simple?

    Tim

    timothyw9;8029018

    At the price of a bulb and for a projector of this age there would really … At the price of a bulb and for a projector of this age there would really be no point.As it is relitevly old I would think the method of bulb detection would be relitively simple?Tim



    If you tell us why you want to do this, it may help us answer it a bit better?

    Banned

    I think he would gain by using a cheaper bulb behind it!

    of course it will never be as good as, but perhaps he doesnt want to spend 100 quid plus for a bulb

    Original Poster

    aircanman;8029072

    If you tell us why you want to do this, it may help us answer it a bit … If you tell us why you want to do this, it may help us answer it a bit better?



    So that I could fit a cheaper halogen. (MR16 bulbs seem to be used on this : jjdogg.wordpress.com/200…ix/)

    If I can get a projector to at least project an image , in Pitch black if needed (velux windows with blackout blinds) It d be cool.....
    Tim

    Original Poster

    dcx_badass;8029081

    What would you gain from this?



    A working projector!:thumbsup: hehe

    timothyw9;8029107

    So that I could fit a cheaper halogen. (MR16 bulbs seem to be used on … So that I could fit a cheaper halogen. (MR16 bulbs seem to be used on this : http://jjdogg.wordpress.com/2009/12/11/broken-projector-modfix/)If I can get a projector to at least project an image , in Pitch black if needed (velux windows with blackout blinds) It d be cool.....Tim



    Ah right ok. Projectors use a discharge lamp, which needs quite a lot of power to ignite first off, I dont think this is recommended IMHO - It may be worth buying a bulb, I know alot of people think the bulbs are very expensive, but if you buy a good quality one, it should last you a long while.

    Original Poster

    jubbyme;8029104

    I think he would gain by using a cheaper bulb behind it!of course it will … I think he would gain by using a cheaper bulb behind it!of course it will never be as good as, but perhaps he doesnt want to spend 100 quid plus for a bulb



    Pretty much yeah.

    timothyw9;8029120

    Pretty much yeah.



    After having a little look at what you would need to do, is it really worth it?

    You need to find out where the power circuit is that tricks the unit into thinking there is a bulb in it, you then need to use a ELC standard bulb in it, with a possible custom mount for the bulb, with a seperate 12V power supply to power the bulb, because the psu in the projector will probably blow it up straight away.

    All for a sub standard quality picture? Surely you can get a bulb for around £75?

    Original Poster

    aircanman;8029137

    After having a little look at what you would need to do, is it really … After having a little look at what you would need to do, is it really worth it? You need to find out where the power circuit is that tricks the unit into thinking there is a bulb in it, you then need to use a ELC standard bulb in it, with a possible custom mount for the bulb, with a seperate 12V power supply to power the bulb, because the psu in the projector will probably blow it up straight away. All for a sub standard quality picture? Surely you can get a bulb for around £75?



    Seems to be about £200 cheapest - filron.com/uk/…888

    Which I wouldnt call cheap....

    If I could use a MR16 Halogen bulb, powering it would be as easy as using a computer power supply (via the molex connector).

    The problem in the way though is trying to figure out what causes the projector to display the splash screen. (aka. makes the bulb known to be present.)

    timothyw9;8029163

    Seems to be about £200 cheapest - … Seems to be about £200 cheapest - http://www.filron.com/uk/index.php?act=viewProd&productId=241888 Which I wouldnt call cheap....



    Bloomin hell that is not cheap lol, still, I would say its better than the other way!!

    I am sure u can buy a projector for that much!

    Banned

    yep, 190 quid plus :?

    did edison hand make it or something?

    jubbyme;8029177

    yep, 190 quid plus :?did edison hand make it or something?



    These are the same style bulbs in the super white light car headlights, they cost an absolute fortune to replace, because of the power they need to light, I am not 100% up on them, but they have a gap filament, which basically acts like lightning going from one end of it to the other, cost alot more to make!

    Original Poster

    jubbyme;8029177

    yep, 190 quid plus :?did edison hand make it or something?



    He did.....

    I can see why projector bulbs are expensive (the way they have to be produced, the accuracy etc to keep it all safe and offer highest performance., even though it can be a pain.

    Original Poster

    bumpey

    If there's a bulb checking circuit in place, what it'll probably check for is that the circuit is closed (ie, there's a bulb in the middle of it, so those likkle electrons can make the round trip), and that the resistance is correct. Stick a suitably resistive resistor in where the bulb should be, and the circuit should be none the wiser.

    How you find the correct resistance of a live bulb, I don't know. Googling for specs might work, as might an email to the manufacturer, or a multimeter on a fully-working second unit. Good luck.


    Edit: Oh, and be careful with it. Electricity can really hurt.

    Original Poster

    dxx;8029553

    If there's a bulb checking circuit in place, what it'll probably check … If there's a bulb checking circuit in place, what it'll probably check for is that the circuit is closed (ie, there's a bulb in the middle of it, so those likkle electrons can make the round trip), and that the resistance is correct. Stick a suitably resistive resistor in where the bulb should be, and the circuit should be none the wiser. How you find the correct resistance of a live bulb, I don't know. Googling for specs might work, as might an email to the manufacturer, or a multimeter on a fully-working second unit. Good luck.Edit: Oh, and be careful with it. Electricity can really hurt.



    Thanks for the help, makes sense, either that or it requires certain wires to be shorted/grounded/something to trigger it to think the lamp is connected.....to be frank itd help if they if they didnt use stupid torx screws.., that would make getting to the ballast a helluva lot easier so that i can see the circuitry - as i currently cant get to to it because i dont have the right size..

    I can see being shocked by a ballast hurting a helluva lot more than a 12v power supply (Having shocked myself a couple of times on a PS2 or XBOX modding)


    Thanks,
    Tim

    Original Poster

    Having succesfully gotten to the ballast/power supply, I am now stuck finding out how to bypass it.

    This guide seems to be the answer: diyaudio.com/for…tml

    I assume it is talking about the two wires that connect to the bulb... my problem being of course I dont possess a multi-meter. Is there any other way of finding 3v? (Or assumably 3.3v ish as thats one of the voltages the ballast / psu sticker has on it.) I dont want to go frying the thing for the sake of a 50/50 chance...

    Tim

    Original Poster

    Just for general working out information, the sticker specifies this:

    INFOCUS 510-1486-25
    Magnatek Model 3979-03-100
    Input 100-120V/230V ~ 4.5/1.8A
    Output 75VDC @3.6A, 12VDC @ 1A,
    5VDC @ 1.5A, 3.3V @ 3A, -8.5V @ 0.25A

    I assume the 75V output power is either what strikes the bulb or what the bulb runs at.


    Tim

    Original Poster

    from a post in the thread, could the lamp optocoupler need jumping?

    diyaudio.com/for…tml
    Post a comment
    Avatar
    @
      Text
      Top Discussions
      1. Just heard this...2 ★★★★★★★★★★★★★★ congrats to all on 392k ★★★★★★★★★★★★★★7764207
      2. How dangerous is Donald trump?31137
      3. ❅☁☁❅ I want☼to talk☼about the☔WEATHER☔no politics☃no religion❅☁☁❅18846166
      4. Microsoft Gamescom - Possibly more free games / Project Scorpio44

      See more discussions