Well, if any of you here have a DLP projector (mine is a InFocus 7205) that is experiencing white vertical lines and/or black horizontal lines... I HAVE A FIX!
Simply, the problem is the connection between the DMD board and the DLP light processor. I took mine apart, cleaned contacts and even replaced the DLP chip trying to correct the problem with no success. But, I did realize that the black bars had become one after one of the times I took it apart and the pattern of white lines had slightly changed and a few were blinking in and out. It had to be a connection problem, not a chip or component failure. After pulling the light engine for the 5th time, I looked at the DMD slot board that the DLP chip is attached to, and noticed the problem, plain as day, right there in my face. Think Xbox 360 problem here, and you start to realize where I'm going with this. The heat sink is attached on 4 corners and uses 4 springs on this model projector to hold down a clamp that sandwiches the PCB of the DMD, the "spring tooth" connection interface, DLP chip and finally the light engine housing. By applying the force on the 4 corners, and not anywhere in the middle, and high heat of a unit like this caused the PCB of the DMD to warp. The clamp, 1/4" think cast aluminium warped as well, so it doesn't hold the entire unit tight in the middle. The teeth on the "spring tooth" component are so minuscule that even a mm would cause them to lose contact.
So, to fix the problem, I used some layers of heat-sink foam (scavenged it from a Plasma TV that I have torn apart that needs to many parts to fix) between the heat-sink and the 1/4" aluminium clamp. And, fixed! It doesn't fully rid the PCB of its warping but it clamps the chip tight enough that it solves the problem. If I had a CNC mill I would mill out a new clamp out of high grade solid aluminium to fix it in a more professional way, but oh well.
If any of you have these projectors laying around and dont want to fix them, I'll take them
if you want to fix them, go for it and feel free to ask more questions. I'll attach pictures of what I have done below.
sorry, forgot to take a file picture of it re-assembled.
Matt
Simply, the problem is the connection between the DMD board and the DLP light processor. I took mine apart, cleaned contacts and even replaced the DLP chip trying to correct the problem with no success. But, I did realize that the black bars had become one after one of the times I took it apart and the pattern of white lines had slightly changed and a few were blinking in and out. It had to be a connection problem, not a chip or component failure. After pulling the light engine for the 5th time, I looked at the DMD slot board that the DLP chip is attached to, and noticed the problem, plain as day, right there in my face. Think Xbox 360 problem here, and you start to realize where I'm going with this. The heat sink is attached on 4 corners and uses 4 springs on this model projector to hold down a clamp that sandwiches the PCB of the DMD, the "spring tooth" connection interface, DLP chip and finally the light engine housing. By applying the force on the 4 corners, and not anywhere in the middle, and high heat of a unit like this caused the PCB of the DMD to warp. The clamp, 1/4" think cast aluminium warped as well, so it doesn't hold the entire unit tight in the middle. The teeth on the "spring tooth" component are so minuscule that even a mm would cause them to lose contact.
So, to fix the problem, I used some layers of heat-sink foam (scavenged it from a Plasma TV that I have torn apart that needs to many parts to fix) between the heat-sink and the 1/4" aluminium clamp. And, fixed! It doesn't fully rid the PCB of its warping but it clamps the chip tight enough that it solves the problem. If I had a CNC mill I would mill out a new clamp out of high grade solid aluminium to fix it in a more professional way, but oh well.
If any of you have these projectors laying around and dont want to fix them, I'll take them
if you want to fix them, go for it and feel free to ask more questions. I'll attach pictures of what I have done below.sorry, forgot to take a file picture of it re-assembled.
Matt
