Please note that this is my first instructable and that the project is still WIP.
My projector is a toshiba TLP-T521 and I want to convert it the a led light source.
I have sourced all the parts and i'm still waiting for some to arrive, I will update this with the new steps once I receive the parts.
So far I have managed to bypass the bulb check and run my LED with a boost converter but it had problems. The image was to dim and the LED was flickering.
Step 1: Prologue
For anyone who just wants to see the project skip this step as it will just be a bit of history ;)
I'm currently 15, when I started this project I was about 12 or 13.
I had wanted a projector for a while but could not afford a new one for a few hundred, I needed one under a 100 euros. It was one of my first times buying online. I went on ebay and searched for a few weeks finding lots with blown bulbs for very cheap prices but bulbs were expensive so I wanted a working one!
I finally found one marked as working with a bulb for around 60€ so I bought it.
After a long wait for me, being excited to finally be getting a projector it finally arrived and was soon in my bedroom. I turned it on and it had a great image! (one I still remember and want to achieve in the instructsble). But disaster soon struck, 60€ was too good to be true, after a few hours of YouTube videos later the bulb light came on and the projector off!
I let it cool down and turned it back on, it lasted another 10min before that red light of doom came on again. arrrh!
It was bulb searching time, I went online and found the bulb for around 100€, too much for me, at 12 I would have been spending all of my money on a light bulb, it seemed like madness!
I thought to myself: "It's just a light bulb, why can't I use any old one?"
So back online again! I found a few people who had done it but there were no tutorials for my model so I followed the general rule of connecting the 3.3v to ground to bypass the lamp check and it worked! success!
Now I needed a bulb, I didn't know about high powered leds back then and so this is where the project got stuck. I tried car headlamps, overhead spotlights and some others but they were never bright enough. Also I had a lot of trouble mounting them not having a drill or glue gun.
So now we arrive today, the projector sat in a box under my bed for years and I never touched it until a few months ago. I researched again and found out about high powered leds. Well let's hope it works this time!
Step 2: Bypassing the Bulb Check
In this step I had to fool the projector into thinking that it's bulb was working. I found the wire going the ballast and checked with my multimeter. I found a wire at 3.3v I connected it to the ground wire and it worked fine. For anyone with the same projector it was the red and white wire next to the red one that I connected together. Job done!
Step 3: LED
This step I don't recommend you follow because as my step up converter isn't current regulated it's no good for my LED.
First I mounted the led on an old computer heatsink (with fan). I then connected the fan wires the one of the projectors fans in parallel. I then set the boost converter to 32v, connected the led and then a 12v pc psu to power it all.
But here's the problem: I don't know if using a non current regulated supply damaged the led or if it's normal but at above 30v the led starts the flicker between bright and dim. I have tried different boost converters and 12v sources but it's always the same. The leds current draw is continuously varying!
I have now ordered a 100w led driver and a new led.
Step 4: Tests
My first tests were a bit disappointing, I had read about people using 30w leds and getting good results so why was a 100w not that bright! Well as I described in the previous step something wasn't right in my setup.
Keep in mind that this really was a pitch dark room and that it was a big projection. And I think it might now be even dimmer than when I took this photo :/
Step 5: Preparing for My Led Driver.
Now I'm stuck again at the mercy of Hong Kong post! So while waiting for my new led and driver I have completely removed the ballast as the driver should fit in there. I have also removed the first glass in the light tunnel so that the led fits better. In my tests the image didn't seem to change with or without this piece of glass.
Finally I have fitted a relay so that the projector can control the led just like the old lamp. I found a wire going to the ballast that was 4.5v when the lamp should be on and 0v when off.
I used one designed for micro controllers like in the photo but the single version. I connected 4.5v to signal or in, ground to ground and +5v to the IR receiver 5v pin (you can use any 5v pin I just used that one for convenience).
Step 6: After Thoughts
Now my goal is for everything to fit inside the projector and for it to work like normal. The driver should fit where the ballast was and works on 230v so I don't need any extra power supplys. The relay will control the led and I even found a heatsink that fits inside so I don't need to move anything inside the projector for the new lamp to fit! In theory everything should be perfect but I'm still waiting for the last bits!
I will update this once I have fitted in the new stuff and post results. I might even make a video demonstrating it! Who knows!
Edit: I got everything working how I wanted a while ago but didn't update this because the light output is still weaker than I would have liked... I have tried various methods to direct the beam (Reflector's, Fresnel lenses...) but nothing improves the light output! The projector is fully usable as normal but not as bright!
I still haven't made a video but I might do soon. I am also working on a 3d printer so I might make an instructable on that to! Who knows!