I will try to give you a general idea how to fool the projector that was designed to squeeze some extra $$ out of your pocket. I will illustrate it with the pictures taken while I was fixing a certain projector but this model is rare and the idea I want to share with you is general. Sorry, it's not a real 'instructable'. I can't name the exact steps for your particular projector but the ideology will remain the same for any case.

Disclaimer - you are going to work with the device that has several dangerous components:
circuit board with live terminals, high-voltage power supply unit, pressurized lamp that can blow up if not handled properly. Think twice and take corresponding precautionary measures to avoid injuries and death :)

P.S. As you can see from the comments in some cases the old lamp may blow up.
I never faced with that myself and the bulb in my friend's projection TV is more
than 10,000 hours old but this "statistics" is not enough so  "forewarned is forearmed".
The safest (and most expensive) way to avoid this problem is ... to buy a new lamp but this
defies the purpose of this very instructable. The compromise is to study the construction
around the lamp and if it looks weak then one can install a metal mesh screen.
The design is up to you - it should have fine openings and at the same time it should
not hinder the cooling.

robyav5 months ago

sir i have a sony projector vpl-cx76 which i need to convert i have got the led lamp but i am not able to figure out how to fool the projector .i have got the service manual for this projector but i am confused .please help .service manual


ánagy101 year ago

Hi! I have just the same problem with my Benq PE8700. Although I found the service manual in no time (http://www.manualslib.com/manual/249900/Benq-Dlp-Projector-Pe8700.html), unfortunately I was not able to obtain how to bypass the lamp. Could you give me a hand in this?

artemff (author)  ánagy101 year ago
first of all, I don't see the comment you are referring to as to "the same". Can you give more information? Do you want to install another light source or you want to use the old one once again?
In any case, see p.43 of the manual - J1 pin 1 and J1 pin 3 of DMD board - the bypassing starts there.
Lamp hours reset is done through RS232 serial interface - see the commands list on p.60 - lamp reset is a "public function" accoding to p.59.
artemff (author)  artemff1 year ago
OK, then check what's going on with these pins #1 and #3 and try to emulate the signal "original lamp is working" (I understand that pin #3 is responsible for that) when the lamp power supply board is unplugged. When you succeed, just swap the light source.

I'm sorry, you are right. I would like to change the lamp to a LED source

repa321 year ago

Hi, I need help as well. I have got an Acer P1220 projector. I reached the lamp changing time but did not care to much when I had a problem and switched off all fuse in the house finally when I could switch on my projector there was a big sound and went off my projector. Probably it is the lamp, that's why I checked the lamp type I mean the cheap solution to buy only a lamp with the same parameters. When I received it I recognised the wire which goes to the lamp is broken as well. So I went to the electrical company who put a cellotape on it. I tried to pu everything together how I found earlier and switch on. Fans start but the lamp is not and after a couple seconds the lamp warning light start to flash and switches off itself. If you can give me any idea to fix it it would be fantastic.


artemff (author)  repa321 year ago
you can upload the picture to any of the free image hosting sites like picasa and provide a link. Another option is to use "add images" button - in my account, I see it just under the "reply" window on the left.
repa32 artemff1 year ago
My email zoltanrepasi37@gmail.com then I can send pictures.
repa32 artemff1 year ago
Hi, I hope that will work. I had this picasa before but did not care about it. Here are the pics. https://plus.google.com/app/basic/photos/photo/106994802370728900426/6020979661870170418?cbp=ro8gslviving&sview=20&cid=5&soc-app=115&soc-platform=1&pct=ab&pcv=6020975390179729217&spath=%2Fapp%2Fbasic%2Fphotos%2F106994802370728900426%2Falbum%2F6020975390179729217&sparm=cbp%3D3z0007leuzxq%26sview%3D26%26cid%3D5%26soc-app%3D115%26soc-platform%3D1%26spath%3D%2Fapp%2Fbasic%2F106994802370728900426%2Fphotos%26sparm%3Dcbp%253D3z0007leuzxq%2526sview%253D26%2526cid%253D5%2526soc-app%253D115%2526soc-platform%253D1%2526pgpnum%253D1%2526spath%253D%2Fapp%2Fbasic%2Fstream%2526sparm%253Dcbp%25253D1b4txjy6qw8ge%252526sview%25253D26%252526cid%25253D5%252526soc-app%25253D115%252526soc-platform%25253D1 and the other https://plus.google.com/app/basic/photos/photo/106994802370728900426/6020979935003841842?cbp=1mghre714ucig&sview=20&cid=5&soc-app=115&soc-platform=1&pct=ab&pcv=6020975390179729217&spath=%2Fapp%2Fbasic%2Fphotos%2F106994802370728900426%2Falbum%2F6020975390179729217&sparm=cbp%3D3z0007leuzxq%26sview%3D26%26cid%3D5%26soc-app%3D115%26soc-platform%3D1%26spath%3D%2Fapp%2Fbasic%2F106994802370728900426%2Fphotos%26sparm%3Dcbp%253D3z0007leuzxq%2526sview%253D26%2526cid%253D5%2526soc-app%253D115%2526soc-platform%253D1%2526pgpnum%253D1%2526spath%253D%2Fapp%2Fbasic%2Fstream%2526sparm%253Dcbp%25253D1b4txjy6qw8ge%252526sview%25253D26%252526cid%25253D5%252526soc-app%25253D115%252526soc-platform%25253D1
artemff (author)  repa321 year ago
I get "Error 400, file not found" when I try to open the links. Can you upload them using "add images" button?
repa32 artemff1 year ago
Im not sure where is that add image button, under the reply I dont have anything.
artemff (author)  repa321 year ago
From this story, I can't establish a link between the lamp hours counter and blowing of the fuses in your house. Can you provide a picture of the lamp and of the "fixed" wire? If it's a hi-voltage wire, a simple patch might not work (in fact, it can be also dangerous since nobody knows where the discharge will happen).
repa32 artemff1 year ago
How can I attach picture? When I put back the fixed wire with the old lamp it started to give burned smell. I switched off straight away. Then I changed the lamp. There was no smell. Worked all fan but no picture and after a couple seconds the lamp light start to flash and switch off. There was a white powder around the lamp after the blast sound.
zopo1 year ago

Hi, I need help with my kodak dp 2000. Here is a photo of boards, i will post more detail photos. http://s22.postimg.org/5v7anikqn/kodak_dp2000.png Thanks

artemff (author)  zopo1 year ago

first of all - do you try to fool the lamp hours counter or to replace a lamp with a LED? Is the projector still working or the lamp doesn't start (in the former case, one can measure the voltages on the logical connector).

Looking at the photos I would say that the high-voltage power supply shares the board with the "normal" power supply, right?

Try to find the circuit diagram for this projector - it will also help.

zopo artemff1 year ago

Thanks for fast reply, i figured it out but right now i'm trying to find some good lens for led but i'm completely lost, can you help me with choosing lens ? I have 20w led, it is about 5x5cm. Thanks :)

zopo zopo1 year ago

Can i use "bi-convex lens" ?

This looks perfect but I'm not shure.


artemff (author)  zopo1 year ago

The only limitation I see is geometrical factor - how much space do you have to install the LED + lens system? I would say that you need at least 68 (focal length)+20 (lens thickness)+20 (LED+radiator)=~110mm.
You can also check this link on LED mods: http://hackaday.com/2013/03/28/epson-projector-led...

zopo artemff1 year ago





Can you sugests me some lens ? :) Thanks.

artemff (author)  zopo1 year ago

hmm, that's a good question - I never tried to make a collimated beam from a source of this size. I would try a telescope-like two lens system, but you don't have enough space for it. In principle, the lens you found might work. I saw schemes with extra reflectors on the sides to return the escaping light back to the system. I would also think about adding a fan to the LED.

zopo artemff1 year ago

Heatstick with fan is on to do list but for first i have to make collimated beam if it is even possible from this led. Btw I'm not limited with space, i can a nev case for projector.

artemff (author)  zopo1 year ago

then I would say that a system of "pre-collimator"+lens+lens will make it close to telescope (go from right to left in this sketch http://www.studydoctor.co.uk/site/wp-content/uploa...)

In any case, you'll need the lens you were going to buy so you can start with it. If the light losses will be too high (only part of LED light will forma a collimated beam) then you can add a second lens and some pre-collimating reflector in front of the first lens.

zopo artemff1 year ago

Thanks for pdf. I just ordered http://pages.ebay.com/link/?nav=item.view&id=171199870428 for start digging dhis optical sh*. :D

artemff (author)  zopo1 year ago

the link doesn't open but, anyway, good luck :)

zopo artemff1 year ago

Ou, damn. Here:


aduy1 year ago
hello, ive got my projector all apart and found the three optocouplers, but the signal doesnt change when I turn the unit on and off even though the lamp light blinks on and off.
artemff (author)  aduy1 year ago
Hello, can you provide more information? Do you mean that the lamp power supply is connected with the main board through optocouplers? I wonder what is the purpose of three optocouplers, one should be enough. Perhaps, the system is sophisticated and the power board sends a digital sequence to tell that everything is OK, but it's an overkill.

Just to be on a safe side - what kind of the problem you are dealing with? A projector with a "native" lamp which is over NNN hours on it and which was working before?
aduy artemff1 year ago
ok so im basically just trying to disable the lamp and trick the main board into thinking the lamp is fine. i have an led light source that im going to replace the lamp with. it is a dlp projector, an optoma ep771 to be exact. i saw a video and it explained that almost all projectors use 3 optocouplers, two of them go from the main board to the lamp supply, one comes back, it seems as if the one that comes back is sending a digital signal of some sorts, instead of a simple on/off it must be sending a code. perhaps ill take it into the local hackerspace and hook it up to the scope and see if i cant decrypt the code.
artemff (author)  aduy1 year ago
another option would be to find the IC which decrypts the signal from the optocoupler and hope that it provides 1/0 on its output.
However, all this seems to be overcomplicated - I wonder why did they choose this approach. BTW, could you add a link to the video you mention?
Back to your problem - do I understand correctly that the projector works, but you want to change the light source? If this is really the case, you can check all the signals with the scope and then try to emulate them. It might require adding something like Arduino, but it should be doable.
aduy artemff1 year ago
I wonder if there is a way to trick the ballast into thinking it is powering the bulb.
artemff (author)  aduy1 year ago
this _might_ be possible (the lamp and the ballast have different voltage/current characteristics, especially during the ignition cycle), but this would kind of defy the purpose - you wanted to use a different light source and here there will be two parallel systems, one of which will be just producing heat.
I would still try digging in the direction of making the main board believe that the lamp is present through simulating the logical signals.
(of course, it would be much easier if the projector could be assembled back to working condition)
artemff (author)  artemff1 year ago
I guess you saw the diagram on p.15 of the service manual - indeed, the lamp module talks to a mainboard (RxTx to DDP2000 module), so it becomes tricky and your solution might be not so bad - otherwise you'll have to emulate all the signals somehow.
dtommyd2 years ago
It looks like folks are still looking at this thread so I'll add a question. Hopefully someone can help me. Instead of photos I actually found the service manual for it. Look for the "Get Manual" link under the preview photo on the download page.

I have pretty much the same question as everyone else. What do I need to jump to fool it? It's for the cp-s210. The photos are a few screenshots of the pdf I linked to. I plan on powering the lamp separately. I just need the projector to power up. I'm also aware of the lamp door switch I'll need to engage.
artemff (author)  dtommyd2 years ago
check page 23 of the manual - it just says "reset the lamp timer". I do not see anything else on the diagram, which would prevent one from doing it for an old lamp, there are no control circuits.

If the projector just doesn't work, then it's a separate problem and the manual contains a lot of useful information regarding troubleshooting.
dtommyd artemff2 years ago
The original ballast and bulb are out of it. The bulb blew. When I go to start it up the blue startup screen doesn't come on. (I am shining a pretty bright 4 watt led bulb powered from 12v outside of the projector.) The main power led blinks green for about a minute (searching for the bulb?) After about a minute the power led blinks red and the bulb led goes to a steady red. It then shuts itself down after about a minute and both the power and bulb leds stay steady red.
Are you saying that if I put any 130 watt UHB or 130 watt bulb in there, it will work? Or are you saying that with the ballast and bulb out, it should be working? Theres no blue startup screen and of course there is no menu. I've done this before with another projector and I'm aware of the dimness and I'm sure I'm out of focus but I was moving that around during startup and see no blue whatsoever.
artemff (author)  dtommyd2 years ago
Do I understand correctly that you try to power it on without any bulb at all?
Then it is not surprising that the power board reports a failure. The question is - do you want to use an alternative bulb and want to fool a projector?

If you really plan to do it then you have to change pin 3 (E804) from "Lamp missing" to "Lamp present" logical level or to remove the power board completely and just put "Lamp present" voltage (check the manual - I don't know the logical level voltages in this projector) to this pin.
artemff (author) 2 years ago
most probably, this is a loose connector or a failure of "blue" LCD chip (this projector uses 3 separate LCDs) or of its driving board. Sorry, I don't know where to get the parts and I suspect that they will be more expensive than a used projector (especially, with a non-working lamp).

I would carefully open the projector, identify the LCD and its connector and slightly move the latter - if the line disappears, then the problem is half-solved (proper restoration of the contact might be quite tricky).

P.S. Usually, there is a safety switch preventing operation with a cover removed.
P.P.S. Be careful if you want to bypass this switch and play with a powered projector - first of all, there's high voltage. Second - it's pretty easy to shorten something or break/misalign LCDs.
kahodges2 years ago
I was wondering if you could help me? I have a used Hitachi CP-X1250 projector that shows a blue vertical line on the left side of the screen, from top to bottom. Which part could cause this, and do you have any idea where I can get parts for this machine? Thanks in advance.
hassan24952 years ago
Hi, thank you for the reply. This is the board attached to the power board which carries the optocoupler circuit. The white on is the signal wire.
there is a good chance it is not just a logic level but there is serial communication between the main-board and the (ballast) high voltage power supply since is a newer projector that can be the case also the proximity to that Nec microcontroller uPD78F0511 can indicate that but I'm not sure.
With a replaced lamp it runs fine. so the rest of the parts are predicted to be ok. Can you help me tricking the lamp ?
artemff (author)  hassan24952 years ago
OK, if it's a real communication between the PSU and the main board, then it's a different story - we don't know the protocol and we don't have hardware to emulate the "OK" signal.
The first idea, which comes to mind is to measure voltage and current for the working lamp and for the faulty one (better with oscilloscope since the ingnition phase might be the cause). The problem is that everything is insulated + you need to solder 1:10-1:100 voltage divider to measure the voltage with a regulat voltmeter and you need to break the circuit with an amperemeter to measure the current - not a good idea.

Another option would be to compare the voltages on all the 'thin' wires, which connect PSU with the main board, for a working lamp and for a bad one. Again, little can be done if the PSU is talking to the mainboard and diagnoses some problems with the lamp.

BTW, how does the lamp look like? Is it just the lamp or something is mounted on it?
hassan24952 years ago
I need your help for my hitachi CPX300 projector. I can not find the signal wire.
It has five wire besides the lamp wire, first one is white and it carries 2.80 v.
next one is ground. rest three caries 15 volt.If I run my projector the end wire ( gray) caries 11.35 volt, rest others stay unchanged. My lamp is 200 hours used, enough bright but shut down after two min. Service center said the lamp is gone. So want to bypass the signal that makes my lamp not working.
Which one is the signal wire? what is the logical voltage ? what will i do to fool it ?
artemff (author)  hassan24952 years ago
first of all, are you sure that this is the board, which powers the lamp?
I don't see hi-voltage elements (transformer, thick insulated wires).
May be they are hidden somewhere but to be on a safe side I'd trace the whole chain from the lamp to the main board. I also understand that 200 hours is nothing for the lamp and I wonder why they told you to replace it. A standard lifetime of a lamp is on the order of 1000-2000 hours.
If the projector goes on and then off, it may indicate a malfunction of the power supply board for the lamp or the overheating due to a malfunctioning fan or a temperature sensor fault. It's just a guess on the information I have at the moment.
hassan24952 years ago
please help me for my hitachi cpx300 projector. i can not find the signal cable. I want to bypass the lamp.
five wire comes from the board. the white carries 2.80 V next one is ground, the other carries 15 v. if I run it the end wire becomes 11.35 v, others does not change ( you can see the wires at picture)
which one is the signal wire ? what will be the logical V ? Please help
antioch3 years ago
You might want to add "Beamer" as tagword. This is what a rojector of this kind is called in parts of Central and Eastern Europe.
artemff (author)  antioch3 years ago
good idea, thanks.
Actually, I made so-called "Volksbeamer" quite a while ago, using a dia-projector and a tiny TV matrix :)
Thanks for the post, very informative. I wonder if you could help me out with my conversion as I'm a bit new to all of this?

I have a Sahara AV 2100 projector with a blown bulb.

I have taken apart the projector and removed the high power board entirely, but am struggling to find the octocoupler or feed to tell the projector that the bulb is OK?

Here are some pictures to give you a clue as to what's going on where, I would really appreciate your help.

artemff (author)  Trying to get a fix!3 years ago
if I understand the photos correctly then I would suspect that the signal connector is the one with 3 pins (with OK letters near to it, I'm speaking about the lower). BTW, where do two thicker wires go and what is written near their connector? Most probably, it's the power wires for this board. What happens if you start the projector with the power board removed? Does it show any signs of life (like a blinking LED)?

Thanks for the quick response!

Yes, that was my guess, unfortunately the pictures have been reduced in size on here, but the other end of that three pin lead connects to the main board and says 'Ballast'.

I have tried the unit with the high power board removed and it still 'works' as before, ie, it starts up, obviously checks for the bulb and then shuts back down.

The two thicker wires on the top RHS in the first photo are from the high power board to the bulb itself, but I had already disconnected the socket from the bottom RHS of the picture (above the blue sleeve).

So, in theory, if I test the voltage of the three pin 'ballast' wire when the unit starts, I should notice a drop in voltage once it shuts down again?

artemff (author)  Trying to get a fix!3 years ago
I actually meant a white connector with two wires that can be seen in the left corner of the board in the lowest panel. As for the "ballast", I'm not sure since the ballast wires should be thicker.

In general, the hi-voltage board must have two power wires, two high-voltage wires which go to the lamp, and XX signal wires which go to the control board. There should be no direct coupling of power to logic (or high-voltage to power or high-voltage to logic). We are looking for the "logic" wires. Can you identify where are three thin pins connected to on the main board? I suspect, one is the ground, another one is +5V, and the third one is "our" signal wire.
Well, after a little playing around following your advice, I've managed to convince the projector that it doesn't need a bulb anymore!

Thanks so much for the help and advice!!

All I need to do now is sort out a new light source!
artemff (author)  Trying to get a fix!3 years ago
Congratulations !
Now you can write your own instructable :)
ikaros453 years ago
This is an AWESOME work guys. Really appreciate it.

I would have one more questions. I'm trying to replace the bulb of my beamer (toshiba TDP S20), and was thinking of a high power LED (http://www.youtube.com/watch?v=Yx0G-4xfMRc&feature=related)

It seems this projector checks whether there is bulb or not with a high voltage signal. So, let's suppose I can fool the control system, but what about the high voltage? isnt it going to fry the poor led? is there any way to get rid of that?

Thanks a lot in advance.
artemff (author)  ikaros453 years ago
First of all, one has to forget about using the high voltage power supply
to power the LED. There are special high-current, low voltage power supply units, check the specs of your LED and google "powering the powerful LED"
If possible, remove the high-voltage circuit board or at least
cut the power to it. The last thing you want in your projector
is the arc between the unplugged hi-voltage connectors.
I doubt that the beamer checks the high-voltage directly without voltage divider.
In this case you may fool the system by simulating the correct (low) voltage
on the input of the control board.
Can you post the pictures of the bulb board somewhere and provide a link?
In any case, I would split the tasks:

1) First, try to make the projector running without the high-voltage
module (use a flashlight in a dark room to check if the system works).

2) When this part of the work is done, make the LED working, align it properly,
and so on.
artemff (author)  artemff3 years ago
actually, the voltage dividers are unsafe - the correct way of interfacing the
high voltage with low voltage circuits is the optocoupling. In any case, the control board should receive the low voltage signal and your task is to identify the corresponding wire, cut it and put a correct voltage on it that will make the control board thinking that the bulb is there and it's working properly.
Thanks very much for the quick answer.

Yeah, I understood I have to shortcut certain pins of the optocoupling (which i'm not really sure what they do, but let's skip that point =)

This is the pic from the high voltage board:


Taken from a german thread on a DIY forum:


And I understand that I have to shortcut the pins 2 and 3 from the white port. I did but when I switch the beamer on, nothing happens and a small LED control for "Lamp" blinks. Exactly as before shortcutting.

So far, the goal is just to make it work... I don't care too much if I have to put an externar powersource for the LED.

artemff (author)  ikaros453 years ago
let me check - did you remove the connector and shortcut the pins or you
just make a shortcut on a cable that is still attached to the board?

My understanding is that one has to unsolder the connector and shortcut
the pins (or just put a piece of wire to the other side of the connector and
make a shortcut there). If you have exactly the same model like posted
on the German board this trick should work (and make sure that the lamp
lid safety switch is activated).

Thank you a lot!!

Now I'm just curious about how to get rid of the high power part. Do you think it's a good idea just to remove the small transformer? without it, everything stays at low voltage.

By the way, do you think a 50W LED is a good option?

Once again, thanks a lot!

artemff (author)  ikaros453 years ago
you may remove the transformer or simply remove the board as a whole. It will give you more space (to mount the power supply unit for the LED).
Average efficiency of modern LEDs is ~50 lumen / watt so with 50W LED
you'll get something like 2500 lumen light source that is of the same
order of luminosity as an average projector. It's not guaranteed, though, that
you'll efficiently collect all this emitted light and throw it to the LED chip
but on the other hand, making the screen 1.5 times smaller increases the
brightness by more than two times. Watching the movie at daytime and
at night also makes a big difference. Check the specs of this LED and if
it produces more than 2000 lm then you are on a safe side.
BTW, with 50W LED I would seriously think about the cooling.
Usually, these LEDs are mounted on the fan-cooled radiator.
Hi again,

You mean removing the whole board... i.e.:


I'll try later if it works without it but uhm, if I had to bet, I'd say it won't. But it could be good to get extra space yeah.

Do you think it's possible to get power directly from some point of the projector? or I just better go to an external power supply.

I thought that... normally these projectors are using 130-160W, so I wouldn't have to install any extra cooling. 50<<<<150W... I'll anyway be really careful on this point.

Thanks again!
artemff (author)  ikaros453 years ago
1) I don't know why the projector should bother about the mising high voltage power supply unit once you have shortcut the signal wires.

2) I doubt you'll find the point where you can get necessary voltage and current
from. Moreover, it's a good idea to have a variable power for LED so I would
buy something specifically designed for this purpose (~3.5V, at least 15A,
check the specs of your LED).
Hi again,

You were right. Works like a charm without the powerboard.

Yeah, the easiest way is to use an external power supply. There are some LED kits that come with a LED power driver that allows you control the light by PWM, like this:


The problem with this kit is that the driver only works till 10W (what a non-sense to sell it together with a 50W ), so I'm looking for other combinations... preferably directly from AC. There are cheap powersources but without power control. Any idea for this?

Btw, these high power leds work around 15v or 30v, depending on type.

And... I've seen that some people use this kind of lense together with the LED... I guess is to make a zoom effect and concentrate the light.


I'll upload some pics when everything's working

artemff (author)  ikaros453 years ago
first of all, congratulations :) The first part is finished.
Regarding the LED driver - it's really strange to sell a 10W PSU for 50W LED.
May be there's a mistake in the description? I'd ask them before making a purchase, anyway.
Regarding the lens - most probably, it's a collimator lens. You put a point light source in its focus and get a "parallel" beam. The only thing to watch is the focal length since you are limited in space by the walls of the projector.
Hello again,

I tried either by conecting the two pins by putting a wire between the pins 2 and 3 in the connector, or just by removing the isolation of the cables and just putting them together "out of the board".... with no results.

Under a electrical point of view, both things are exactly the same.

This lid safety you are talking about, is a safety system to check that the department of the bulb is closed? I was checking it with the lid open, so maybe this is the reason.

I'll check and tell you later.

Thanks again!!
I am curious as to what model projector this is. It looks very similar to the that i have now. when i found the projector it did not come with a bulb and i am trying to use an alternative source but i think i need to bypass the circuit in order for it to work.
artemff (author)  invisiblelight3864 years ago
the model is kind of rare: ASK Impression A6+
The bulb costs about $350 so the desire to use an alternative
light source is understandable :)
Most probably you'll have to remove the hi-voltage block completely
and use something like halogen bulb or powerful LED.
As I wrote, the key thing is to make the projector thinking that the
light source exists and operates.
You may open the projector, identify the hi-voltage module and
see what wires connect it to the main board (and, possibly, to
power supply unit). Knowing this will help to make the next step.
i have a Sharp pg-d100u. I'm most likely going to use a high power LED for the light source. I think I'm going to probe around the thing this week end to find the circuit for the light sensor and see were it goes from there.

tyler96135 years ago
Not to be a buzzkill, but, just as a warning:


This is why projectors have the built in counter in them. Apparentally, yours may have a sensor, but almost all projectors I've seen have a lamp counter in them. The projector manufacturers put this in place for a reason, to protect its users.

Just sayin.
I have a neighbor who repairs TVs I've talked to him about these bulbs. Explosions are an extremely rare exception, not the rule with these. That said I have seen brand new ones "blown up" as well when owners did something (not sure what as they of course say they did nothing). My repair friend has not figured out what they are doing either. That said, my neighbor also hacks as he calls it, projector TVs for friends and family his brother's original bulb has now been reset for the 3rd time, a savings of around $750
On another note he said many units do not have a counter or a circuit to limit the hours but rather just eventually wear out on their own.
artemff (author)  Bad Maxx5 years ago
I guess, some of them blow up because people don't handle them properly. They open the projector when they want to check the lamp, touch the bulb without special gloves, and leave the skin oil marks on the bulb that leads to uneven heating and cracking of the glass. Some people also turn the projector off using the main switch while they were supposed to pass it through the cooling phase. This also lead to bulb overheating and possible damage. ---- And, you are right, some bulbs simply degrade with time.
That would make sense, I know my first experience with a halogen bulb went like this: Removed bulb from package with bare fingers (no warnings or instructions were included to tell me otherwise) placed in my brand new torché style lamp, enjoyed my new lamp while reading, used lamp approximately 1 week, while relaxing with a good book I heard a faint pop noise and the room went dark. Replaced "popped" bulb, about two days later popped the new bulb.... Called my father and asked him what he knew about halogen bulbs, first thing out of his mouth was "do not touch the glass with bare fingers"! Of course this was in the 80's when these bulbs were not as common as today.
My friend is in the av department at our school, and he tried installing an old bulb in a projector. It ended up blowing up in the middle of class and sending glass shards around the room. Luckily, it didn't get in anyone's eye or anything, but I don't recommend messing with these things.
artemff (author)  jimmy dean5 years ago
OK, sorry about your friend. I've heard about that, too but with a less scary scenario. However, even a brand new lamp can blow out if one touches it with naked fingers while installing it (the skin oils will lead to irregularities in the heat transfer that increases the risk of the lamp failure).

Another thing to check is the construction around the lamp: in my projector everything is solid and even if something happens the parts will remain inside.
Other projectors might have a different build, so - think twice, weight all "pro" and "contra" and then act but it's typical for many instructables :)
excuse me if i have put this on before couldnt find it on the site,anyway can you use a flourecent tube starter to strike the ark,then a normal halogen bulb connected to a separate supply or just tapped inside the projector.
artemff (author)  1000000VOLTS5 years ago
Let me check my understanding. Do you want to use some other
high-voltage bulb?
Then it's getting tricky since you have to solve two
tasks: 1) fooling the projector and 2) using an (unknown) lamp with a
(unknown/third party/self made) power supply.

The second part might be trickier that the first one.

BTW, recently I found that there are extra bright and powerful LEDs available for
reasonable price. For example, Allelectronics had one for $5. It's a single point light source and it's easy to work with.

thanks for your reply i was going to fool the projector by putting the flourecent tube starter the ones that constantly click when they are old. in replace of the broken bulb, because they strike an arc doing a similar job to the original bulb and then use a halogen bulb or leds doent matter whatever is brightest on there own power supply , i just need to fool the projector would the starter thing do this.
artemff (author)  1000000VOLTS5 years ago
Now I understand what you want but I wouldn't go this way.
The unit will measure the voltage drop and the current at and after the
arc and if the parameters will be off specs it will generate "FALSE" signal.
Why don't you want to find out which wire is a signal one and what is the
level of the "TRUE" signal? Then you'll make it in an elegant (and safe) way.
There shouldn't be too many wires coming to/from the ignition/power supply module.
ok i will try it your way seems a bit complicated to me electrics is my thing not electronics ,i will let you know how i get on cheers
amp20095 years ago
hi im also looking into replacing the current bulb for a led. i found a 100w led that claims 7000 lumens. im hoping this will be bright enough as my projector is nec vt560 and in the specs it says its only 1300 lumens. thought about using a focusing lens with a reflector to use the most of the light. i was also thinking a heatsink and aditional fan on the bulb housing. what do you guys think? this instructible is awsome if i can get the projector to think that the bulbs working ok then ill be so so happy.
artemff (author)  amp20095 years ago
I would suggest splitting the task to two: first, make the projector
working without lamp (and better yet without the lamp ignition module since this will eliminate the high voltage in your unit). You can use any light source
in the dark room to check if you succeeded (use a small throw distance).

After that you can play with the LED source - I think the heat production will be comparable to that of the bulb so you'll just need a good heatsink. The fan
is already there. But may be you're right and you'll need extra airflow.

Please, write a brief comment here if you manage to get a reasonably bright picture.

and when youve taken out the ignition circuit you could make a nice tesla coil out of it lol
ive only got 200 hours left and like the rest of you dont want to spend a fortune on bulbs,i have two phillips  lc1312 or somthing like that one with bulb other without the one without has a green screen cos the ribbons have broke ,not by me so i dont mind playing with it,i understand the risks of high voltages .lol.if the thing can be fooled into thinking there was a bulb in there any bright bulb would do ,i think the Hg bulbs run on about 20kv and need an arc to set em off correct me if im wrong..same as the flourecent tube starters.so before i kill it does anyone have any objections to that aproach.cheers.i was thinking of putting the starter on a direct short across the two bulb wires ..
abadfart6 years ago
nice i have an old epson elp-3300 for a tv this might work seeing as how it is from the 90s
fred416 years ago
hi It seems that I have the same projector as you infocus lp720... when my lamp shutted down, I trowed it and replaced it with a "deported" other lamp, hotter, but cheaper. all work fine but, i can't pass the "blue presentation screen", I already bypass the control module 2. So my question is : did I only have to cut the black wire you show on "step 2", and plug it to ground , the metal case for example, and wich side ? from the board, or the other side? sorry for my english, hope you could help. And why did'nt you produce this how to, two month ago, i would'nt have trow my lamp... so sad...
artemff (author)  fred416 years ago
First of all, my projector is not Infocus, it's a kind of exotic ASK Impression A6. Second, what do you mean by "blue presentation screen"? Third, are you sure you found a correct wire? In general, you have to tell the main board that the lamp is working OK. Check the voltage on this signal wire - if it is zero volts when the lamp is not working, cut it and pass +5V to the main board through some resistor (1KOhm will be fine, I guess). If it is +5V, cut it and ground the wire going to the main board through the same 1KOhm resistor. Hope this will help.
artemff (author)  artemff6 years ago
another comment - just to be on a safe side. My projector doesn't have this signal wire on the control module. I don't know if your projector is of "Type A" or "Type B" (see the steps 2 and 3) so don't mix up the power wires with the signal wire. (I guess you've already found what is what but double-check prior to cutting and grounding ).
fred41 artemff6 years ago
nice fast answer, I will test it and tell you, if I succed or not, the power supplies seems to be the same... thanks
eric9166 years ago
Great hack. But will this mod work with the newer, smaller projectors?
artemff (author)  eric9166 years ago
good question. Frankly speaking, I don't know. To answer this question one has to have a look at the lamp. If the lamp is not damaged (cracked, the glass is black or white from inside, etc) then most probably it will work for another couple of hundreds or maybe thousands of hours. For example, the bulbs in older projection TVs lasted for 10000 hours. So, if you see that the bulb is OK, look for the fuse. I'm afraid that bulb makers will start putting the chip on the lamp housings like they do with inkjet cartridges. In this case it will be trickier but I hope they won't go that far :)
486dx46 years ago
i just use 30 year old bulbs that i found at a shop for a dollar a piece =) the problem is i have to make a metal bracket for them and line them up just right. but i think my projectors bout dead anyway from me rebuilding it like 10 times to try to fix some dead lines lol. i found it for $10 tho so no big loss lol
artemff (author)  486dx46 years ago
you mean that these bulbs somehow match the voltages on your projector? Then you are lucky :) May be you use a separate power supply unit for them?
486dx4 artemff6 years ago
ive actually been thinking about making some kind of custom bright white LED bulb so i basically would never have to get a new one.
artemff (author)  486dx46 years ago
I doubt you'll find one that bright. Just check the specs of the LEDs and that of the bulb. Remember, uou need all this brightness in one point, not in 4x4" area. Otherwise you'll have to redesign everything in your optical system.
486dx4 artemff6 years ago
couldnt u just use a reflector, like the ones that usually come with projector bulbs? some of those tiny little projectors their making these days are useing leds.
486dx4 artemff6 years ago
yep im just lucky =) tho their actually just old slide projector or reel to reel projector bulbs, so it takes some adjusting to get the to work, but the biggest problem is that the hour ratings are usually sub 100