Pssst. Yeah, you. Wanna learn how to build your own digital projector? Last time
we started building our own DIY HD projector. Today we're voiding the warranty and stripping down our 19-inch Samsung display. Next time we'll start preparing the LCD's new living quarters -- that is if we don't end up with a $340 door stop after today.
Tearing down the LCD is one of the most essential parts of building the projector. Mess this up and there's no way you're going to resurrect it. This is where we meet the greatest risk and find out if the display will actually work for our application. One of the caveats here is that some LCDs have cables that end up in the way, making them incompatible. This guide should serve generally, since we don't necessarily expect you to have the exact Samsung LCD that we're using. Your mileage may vary, but hopefully this will be useful in instructing you how to get at the sweet, sweet panel within.
Before getting started with our LCD debauchery, it's a good idea to take some measurements of the actual visible area of the LCD screen. These numbers will be handy later on when we're mounting the display inside our projector. The visible area on our Samsung 940MW-SV 19-incher is 16 x 10-inches.
Before gutting the display, set up a nice clean workspace. We reused some of the packing material - it's a nice soft foam sleeve. It's critical to protect the actual display as much as possible. Grab a small bowl or something similar to put all the screws in as you remove them.
The base is easy to remove, we installed it when we set it up for testing. Loosen the winged screw and it pops off.
The bracket that the base was attached to is held on by these four screws. While we were at it, we removed two screws along the bottom edge of the display. Six screws? Our original Game Boy had more than that!
Once they're out, the bracket slides easily out of the display.
Now that all six screws are out, we need to separate the display housing. Traditionally, we'd damage the edge of the case and pry it apart with a regular screw drive. That gaping hole that we just opened up looks handy. Slide your Phillips head screw driver into the slot and gently
pry the casing upward. Ours came apart with no damage to the outer casing.
Once the cover pops up, it lifts up and away from the heavily shielded battle station
... uh, display.
On the left side, we find the IR receiver board. Just above it we find the control buttons and one of the speakers. We want to re-use the IR receiver in the projector, but we're leaving the speakers out of the equation.
On the right side we find the connector for the controls and the opposite speaker. That long wire on the controls looks handy for the conversion.
Each of these unplugs pretty easily, just use gentle force and they come right out -- once the tiny locking tab is depressed. Press the tab and work them loose.
Remove the single screw holding the IR board in place and pull out the controls. We'll need these later.
Now that everything is clear, we get to start in on the fun stuff. First we need to pull the outer layer of shielding to expose the control board and power supply. We start by removing all the screws around the edges of the shielding.
The side RCA cover slides right off once the two screws anchoring it are removed.
With all the screws out, the shield lifts off to expose the power supply on the left and the controller board on the right. Now's a good time to point out that charged capacitors are dangerous
, so know what you're doing!
The power supply ribbon disconnects easily, these connectors for the cold cathode lamps are a real pain to remove. We had to unscrew the board from the mount before we could get at them.
Once the power supply is out, place it on some of that convenient anti-static packing. Watch those capacitors, man!
Now that everything is disconnected from the controller but the actual LCD, we can remove it and get to work on that final connection.
This connector is another painful part. The ferrite core is attached to the shield with some double sided sticky tape. We partially disconnected the cable, then pried loose the core, then finished the job. Once again, it's critical that these components aren't damaged. Once it's out, remove the controller board to a nice safe place -- a good place might be next to its old pal the power supply.
With all of the external electronics out of the way (we don't need no stinking speakers) we remove the last of the shielding. Inside we find our precious, the 19-inch display.
The display lifts out of casing easily, once it's out, chuck the case and get the display to your nice soft work area. The display is a bit of a high tech onion. We'll have to peel off the layers to get the display free of it's usual garb.
Whip out your tiny screw driver and remove the three small Phillips screws holding the top of the case together. If you don't have the right driver, we've found that the small nail file blade of a Swiss army knife works in a pinch.
With the screws out, the cover flips off to reveal a bit of PC board and the 'flat flexible cable' (aka FFC) ribbon that connects to the actual LCD display. Be very careful here, this is the most vulnerable part of the display. If these are damaged the whole thing could be ruined. (Remember that voided warranty.)
Now's the time to deal with those pesky cold cathode lamp cables. We removed the white cable guides, but we really didn't need to. They're stuck down with more double sided tape. Removing the upper one did help us figure out the casing a bit easier.
Work your way around the edge of the casing and pop each of the lock tabs apart. It requires gentle force and the use of a small flat screwdriver.
Once you're popped all the tabs, the front frame should pop loose. Once it's off you're free to remove the LCD. (We didn't realize it and kept going... but that's all you need to do in this case.)
Remove the frame and lay the display face down. Lay out the FFC cable on your work space. Now the backing should lift away from the display.
There it is. This panel is the key to everything. On the right we can see some FFCs that connect the edge of the display together. We'll have to watch out for these when we frame the panel into our enclosure.
Phew! That was a harrowing experience. We forgot to mention one extra cost. The massage therapy session you'll need after spending an hour knowing that a mistake could cost you a $340 LCD panel. It was really pretty easy to disassemble, but don't try it if you're having an off day. Next time we'll frame up the panel and get started on the projector housing. Watch out!