Fooling the projector

Picture of Fooling the projector
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.

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zopo2 months ago

Hi, I need help with my kodak dp 2000. Here is a photo of boards, i will post more detail photos. Thanks

artemff (author)  zopo2 months 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 artemff2 months 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 zopo2 months ago

Can i use "bi-convex lens" ?

This looks perfect but I'm not shure.

artemff (author)  zopo2 months 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:

zopo artemff2 months ago!UYUyhYbA!FIHN2aWoTaoZbm1iKLAGHbOgv-jlfFTx7sOhv0E58WI!pZMRhZ5B!W_m71ccSC2dIt0diyVBFQApQ0muOs7U7V1-qPetPFXw!RAdAmTZL!8r1_dmlmRmyspmOixdHG7S3oe7E2HxiLZpgPOdM_7S4!xUURwJ5Q!Ma6_rM325ZpoYJgAa0EDvkm9sY6fpHYA8jqdQHpZ348

Can you sugests me some lens ? :) Thanks.

artemff (author)  zopo2 months 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 artemff2 months 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)  zopo2 months 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

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 artemff2 months ago

Thanks for pdf. I just ordered for start digging dhis optical sh*. :D

artemff (author)  zopo2 months ago

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

zopo artemff2 months ago

Ou, damn. Here:

aduy3 months 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)  aduy3 months 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 artemff3 months 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)  aduy3 months 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 artemff3 months ago
I wonder if there is a way to trick the ballast into thinking it is powering the bulb.
artemff (author)  aduy3 months 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)  artemff3 months 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.
dtommyd1 year 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)  dtommyd1 year 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.
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)  dtommyd1 year 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) 1 year 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.
kahodges1 year 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.
hassan24951 year 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)  hassan24951 year 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?
hassan24951 year 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)  hassan24951 year 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.
hassan24951 year 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
antioch1 year 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)  antioch1 year 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!2 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!2 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!2 years ago
Congratulations !
Now you can write your own instructable :)
ikaros452 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 (

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)  ikaros452 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.

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