Sunday, December 6, 2009

Neck Ache: Part 6.5

I have been scrambling the last week, working on school stuff as the term comes to an end. I also have finals next week. After that there's the hustle and bustle of the holiday season with relatives and driving and such. Long story short (or by now, short story long), posts are probably going to be sporadic over the next month. 


I opened the neck back up and wrapped the ethernet wire with some aluminum tape. I tried to get it down into the super skinny part but the angles were too extreme. All in all, I probably covered 95% of it, but that either wasn't enough or wasn't the problem because the display still had the same issues.


I need to track down some ferrite cores and try those, though I fear even if they do solve the problem, the one that will need to go behind the display won't fit. We'll see I suppose.

I'm still in the process of trying to track down somebody who actually knows about this sort of stuff. There's an uncle of a friend who might, and I'm also working to track down some electrical engineering professors... we'll see.

Monday, November 23, 2009

Thanksgiving

So here in the States, Thanksgiving is coming right up which means four days of stuffing our faces in celebration of what can best be described as genocide. But I like to concentrate on the stuffing of the face with family part of the holiday. However, I would like to point out that the whole Native American killing thing should really be blamed on the Spanish (discovering the new world) and the French and English (colonizing) Probably mostly the English and Spanish though because as I understand it the French got along with the Natives pretty well. Luckily, Jinsuk Kim (see comments) and his fellow South Koreans can rest easy knowing they had absolutely nothing to do with that whole ordeal. 

Bottom line is, if I'm lucky I'll have some time tomorrow to troubleshoot this. Otherwise, I'm going to be pretty busy through the end of the holiday so not much will probably be happening here until the beginning of next week.

Saturday, November 21, 2009

Neck Ache: Part 6: More troubleshooting

I spent a little over an hour yesterday with two professors trying to troubleshoot the screen issue. We didn't solve it but we discovered some interesting things. We found that changing the screen resolution affected the flicker rate. 800x600 seemed to be the sweet spot, with very intermittent flickering. However both at higher and lower (640x480) the flickering was considerably worse. The backlights still only stayed on for a second or so.

The best we were able to come up with was the shielding (or lack there of) on the extra wire that I ran through the neck. I'll get around to troubleshooting that either later today or tomorrow.

On a side note, I'd like to take this moment to point out what a world wide endeavor this is. As you can see from this Google Analytics map, the interest in this project is global. I just think this is awesome and every time I get discouraged I can look at this and all the great comments you've all left me and I really get reenergized.


Wednesday, November 18, 2009

Changing Gears

I am currently in talks with two professors who I hope will be able to help troubleshoot the LCD problem. Please don't be discouraged though! If you have any ideas, drop a comment; the more ideas, the better.

Anyway, while this is going on, I'm going to begin work on preparing the base for the Mac mini. The first order of business is getting all the ports of the mini extended to the port openings on the iMac. I had first planned on doing this by getting a custom circuit board made which would be custom cut to fit and have the ports soldered onto the board and then attach extension wires from the board to the mini. In the end however, this proved to be more work than I wanted to invest considering I couldn't find anybody that I could locally take my board to and have it matched for under $1000. (yes the bid was one thousand dollars)

So I move on to plan B: PLASTICS! There's a place (probably several actually) here in Eugene that sell plastics for all sorts of applications. My plan is to take a sheet of plastic, mark it and cut it, and secure off the shelf cable extenders to it (USB, Mini Displayport, etc.)

I started at MonoPrice.com and for the very good price of $16 (shipped) I got 3 USB extenders, 2 3.5mm audio cable extenders, and 1 Mini DisplayPort extender. (all 3 feet) Not to shabby I'd say. I already have the supplies for the ethernet, I'm not sure if I'll use the dial-up modem port for anything, and I was unimpressed with MonoPrice's selection of firewire cables. (mainly, I either want an FW800 male to FW400 female cable or the 800-to-400 adapter and a 400 extension cable, none of which they had)


I did find this pretty awesome FW800-to-FW400 adapter ("Moshi's 800 to 400 FireWire adapter") for about $10 which, depending on how the Mac mini actually ends up sitting in the base, might just be the only FireWire cable I need. I'll wait on that until I actually have the Mini situated in place so I can measure the exact distances.

Sunday, November 15, 2009

Neck Ache: Part 5: yuck

So I had a little chat with my dad this morning and he suggested that it could be a grounding issue. When he was my age he built a dune-buggy with a VW Bug chassis and a fiberglass top. The when securing the instruments to the new fiberglass dashboard, they kinda worked but always gave funky data. He realized at that point,  the instruments were all designed to be grounded through the original metal VW dashboard and since the fiberglass wasn't conducting electricity, they acted funky. A couple jumper wires later and he was in business.

Fantastic story really, and it all seemed to fit so well into the problems I was having. On the video card and power supply, all the screw holes on the boards are surrounded by solder as if to make sure there's a good connection between that point and the metal housing they're all connected to.

Well it turns out grounding may have been some of the problem, but I'm not sure how much this actually had to do with this. (granted, all my testing was done with all the screws securely screwed into the original metal housing)

I had the exact same symptoms as before: staticy picture with no backlight. However, I made the discovery that the reason the I got no image or backlight yesterday was because I had taken the rear of the display off and hooked the neck directly to the LCD. If the metal chassis the LCD sits in was not in contact with the metal inside the back of the display, there was no image what so ever.

I did have one interesting revelation however. With the monitor still on showing the staticy image from my computer, when I unplugged the VGA cable from the monitor, the backlights came right on and the monitor's dialog box saying "No display connected" (or something like that) flashed on for about 1 second. It was crystal clear, just the way it should be. However, after that one second, the backlights went out. The message still seemed to be there just as clear though or a second or 2 more.

I also tried hitting the monitor's menu button and the menu did come up, but the backlights didn't turn on. This is very strange.

Saturday, November 14, 2009

Neck Ache: Part 4: Ugh

Right-o lets get this over with. 

Took this super tiny piece of wire and soldered the two broken ends together. 

I know it's not the prettiest thing in the world, but the three bits are securely attached to each other. A little electrical tape and I should be in business... Should....

So at this point, I plug everything in to test it. It doesn't work of course. Here's what happened: The backlight turns on for a second and then turns off again; the status light is amber. I wiggle the video wires a bit and get the backlights to stay on and on the screen I get black static. Wiggle the wires a little more and the black static turns a little bit into the image of what it should be showing but with lots of static and the status light turns green. A wiggle later, the backlights are off again and there's not even a black staticy image left on the screen. However, the status light is still green. 

If you click on the image, you'll get a bigger version. Notice the LED is still green and there's nothing on the screen...
Now in the process of doing all this, I removed the neck from the LCD back so I could get to things easier while I was troubleshooting. Unfortunately, I couldn't think of anything else to do. I went back and multi-metered all the video wires and everything connected right were it was supposed to be and there were no exposed wires touching themselves or anything like that. 

I'm really out of ideas. It doesn't seem to be a problem with the backlights because they were functioning perfectly when they were on. The LCD itself seems to be doing well: when it did show a staticy image of my computer, besides being staticy and stretched, the colors were all accurate and things seemed to be in the right place... I don't know, but that's enough for tonight anyway... 









Friday, November 13, 2009

Neck Ache: Part 3

With the bottom cable all soldered up It's time to move on to the top half. Instead of soldering the top half, I gambled and decided to just replace the pins. The gamble was that even though they're the same size, the pins on the iMac's cable might pull out easily if the little plastic keepers don't go all the way back down.

So I just grabbed my handy x-acto knife and carefully pried the little keeper bits up the smallest amount possible to release the wires. Once I had them all out, I consulted my pinout (see bottom) and started plugging the iMac's wires in. Because of that pesky extra green wire, I stole the green wire from above and soldered it to the green cat 5 wire I ran so it would fit into the adapter.

It actually took me a really long time to get all those tiny little wires pushed into the plastic thingy. But I eventually got it.

Like i feared, many of these wires aren't really in there all that well and tend to want to slip out with relative ease. I'm not 100% sure how to remedy this issue. I thought about hot-gluing where the wires go in but I'm paranoid about melting any insolation or screwing anything up like that. For the time being, I just flattened out the wires and wrapped them in electrical tape.

Once the video cable was all finished, I moved on to the backlight wires. For these, I'm using the cables Apple allocated for the Inverter to run the two pairs of backlight wires. I started by cutting back the heat-shrink on the backlight power cables.

Incase you haven't noticed, I have a lot of... lets say, "special" moments. I get it into my head that I know what I'm doing and got it all figured out, and then, do something really stupid. Like cut off the the end of that video cable! grrr... Anyway, in this installment of "Dave's Super Special Moments", (most likely brought to you by leaded solder), instead of cutting off end so I have the connector part to solder onto the bottom, I just pulled off the plastic part as I've been doing and soldered the the plug ends right to the inverter cable, or rather, the cable that plugs into the inverter cable:

This is the cable that connected the original inverter to the inverter cable right behind the display.
Anyway, so that was dumb. Luckily, since I just happened to have some spare monitor parts lying around (weird, right?) so I was able to solder on the end from that:

So, that's it. Everything was ready for the big test. As of that moment, I was 50/50 with this monitor stuff working. After I got everything hooked up and turned the monitor on... it didn't work. Now at this point a familiar feeling of dread passed over me, but I was able to shake it off and go right into troubleshooting mode.

Symptoms: The backlights turned on for a second, then turned back off. The picture on the screen was present even after the backlights turned off and was very fuzzy.

Testing: I grabbed my multi-meter and began testing to make sure all the wires were still connected and no exposed wire bits were hitting any other wires. I did the continuity test on the inverter wires first, and they all checked out. I then moved onto the video cable.

I made sure each of the wires was where is was supposed to be based on my pinout. All good. Then I did a continuity test from the black connector that plugs into the video card to the plastic thingy (above) that plugs into the back of the LCD, making sure that there were no broken solder points. I also wanted to make sure there were no exposed wires touching other wires, so while I had one end of the multimeter on a wire in the black connector, I slid the other lead of the multimeter across all of the gold ends on the plastic thingy and made sure it only beeped when touching the right pin. A lengthy explanation for a lengthy process.

Anyway, after doing all this, I found that a single wire had managed to go and get broken.

That's right, that little bastard, RIGHT THERE, ruined my entire day! To add insult to injury, it was one of those hair-thin stupid wires that was a pain the butt to strip and solder the first time when it wasn't surrounded by a heaping glom of un-shrumk heat-shrink tubing. Yuck.

At this point I grabbed some cookie dough out of the refrigerator and called it a day. I REALY hope that is the culprit and I'll have the monitor fully functional by the end of the weekend. We'll see.

Oh, here's that pinout I promised:

I know it's messy, but it I understand it and that's all that really counts.

Tuesday, November 10, 2009

Neck Ache: Part 2: Soldering

My shrink tubing isn't shrinking all that much when I put it next to a soldering iron. Any ideas?

I was very sad when I shattered the first new $100 LCD panel I got, but that was about it. Right now, I am in a fit of rage over my stupidity in cutting off that flipping cable end. I spent well over two hours today stripping and soldering wires, many of which were no thicker than my hair. I'm not sure which hurts worse, my back, my neck, or my fingers... Anyway lets take a trip back in time and try to figure out how I got here:


These are the devil's wires. They're ones in the black cable. They are so thin, if you showed them to a MacBook Air, it would probably have a kernel Panic on the spot. That's a terrible mac joke, but these cables have damaged my mental stability! Sorry. I found the best way to strip these super slim wires was to take my x-acto knife and lightly cut through the insolation all the way around and pull it off. I should say, even after discovering this trick, I was still less than 50/50 at not just breaking the wire. It sucked. But you wont have to worry about this, because you didn't cut the cable.

The wires in the grey cable are still thin, but soooooooo much easier to work with. Though they are too small for the 20-22 AWG hole on my wire strippers, I found that using the area just below that to lock onto the insolation worked out great. Just don't squeeze the handles together too hard or you might cut the wire.

I used the same trick on the wires that attached to the LCD's video card

Oh forgot to mention, I wen't out and grabbed one of these puppies for $10 earlier today and it saved by butt! They are super great, free up your hands, and you should get one if you don't have one.

When I was at QCM inc. (the cable making place), they nice guy there demonstrated how to properly solder connections such as these. First you get your wires situated right up next to each other as shown below. If, like in this case, they're stranded wires, inter-tangle the wires a little. Then, take you hot soldering gun and melt some solder onto the tip. Then, in a single motion, bring the tip down onto the overlap between the two wires, lay the melted solder along the strands, and pull it back up.

22 wires doesn't sound like a lot. But it is. Anyway, I'm completely burnt out on this soldering business for tonight. The top is just going to have to wait.






Monday, November 9, 2009

Backlight Extension.

These backlights are weird. There's just not much else I have to say about them. But let's get to that in a minute. So as I've discussed before, there seems to be some question as to whether or not lengthening the cables from the inverters to the backlights will cause any dimming of the lights. Well here's what I've managed to come up with:


Can you tell which is brighter? They look the same to me. One of these has a 3 foot cable from the lamp to the inverter, the other's is about 4 inches. And I gotta say, They look pretty identical to me. So, it would appear that lengthening the cable from the backlight to the inverter (at least a short distance) should not affect the brightness of the lamps. Now to the weird bits.

When both lamps were attached via the 3 foot cable, and that cable was coiled up, weird things stated happening. When I touched the aluminum housing on one of the lights, (grounding them I suspect) it got a lot brighter and started humming at some high pitched frequency.

When I touched the aluminum housing of the other one, half of it went out. (It didn't matter where I touched it, it went out in the same place.)

Very interesting. The cable's definitely didn't like to be coiled. When I stretched them all the way out, they both lit up just fine and didn't appear to be affected by being touched.

Note: All 4 of these pictures were taken with exactly the same exposure settings. Their relative brightnesses should be quite accurate. 

Oh, and I really didn't feel up to soldering today. Probably tomorrow though. 

Sunday, November 8, 2009

Neck Ache: Part 1



When I stopped by the cable company QCM inc. and talked with one one of their very nice employees. Long story short, it was going to cost at least $100 for them to do it. However, due to the non-ribbon style cable that came in my new, new monitor, he said it should be easy enough to solder it myself and save myself the money. However, he was kind enough to demonstrate the proper technique and leave me with a bag of pre-cut shrink tubing.

With my knew knowledge, I sat down to make it all happen this morning. Five or so hours later, I've learned a lot, but haven't gotten very far.

I started out by dissecting the video cable that runs through the neck and discovered a few things about it. First off, taking the insulation off of the grey cable, there are 4 wire groups. Each group has 2 wires and one hidden wire: 2 hair thin wires and the shielding around these is the third.


As you can see, these wires all have golden ends. This is because I used an x-acto knife and pried up the little tabs on the on the plastic connector and gently pulled them out intact. This is a very smart thing to do.


Unfortunately I only had the brilliant insight to do this on the top. On the cable coming out the bottom, I cut it before having time to think about it. Please, this is a public service announcement: DON'T CUT THE EFFING CABLE!!! Sorry. I don't like when people use all caps, but seriously, this is important and I am very sorry that I cut the cable. Anyway, yes, if you don't cut the cable, use a small flathead screwdriver to peel back the steel cover.

You will then clearly see it's just another plastic connector with the little gold pins in it. Like before, grab the trusty x-acto knife and peel up those tabs. You'll be treated with this beautiful display of pretty gold bits!

Congratulations! You've just made your soldering life 400 billion trillion billion times easier! I on the other hand am going to suffer as a result of my incompetence. Aren't you glad I get to suffer for you? :)

Well now that that's done, we're still 1 wire short. The new, new monitor's cable requires 22 wires. The iMac's cable, despite the clever shielding trick, only has a total of 21 wires. So it's time to crack the neck and add a new cable. Heads up: this part sucked.

So I wrapped the neck up in an ethernet cable to ensure it didn't explode on me (Fun Fact: turns out they don't explode, they implode). Then using the fantastically made bits I had made, I unscrewed and removed the screws.

Now at this point, it's very important to know which way's up. I didn't know. Thus, as alluded to by my fun fact, it imploded. It wasn't really that bad, but it took blood, sweat, and tears (ok, not tears, but blood and sweat) to get it back. I didn't take any pictures of this due to extreme anger and frustration, but if this happens you to, find a small headed flathead screwdriver with a long, sturdy handle. Stick the blade of the driver into the hole on the back and use it as a lever to align the two holes. Make sure the two pieces click back into position, and you're good to go.



Ahem! So, when you remove the weird 3 pronged screws, underneath them, there are holes. Three of them have one hole. One of them has two. Make sure the one that has two holes is face up. That is the top. If you have it face down, you will have to go back and read the grey instructions above as to how to fix your imploded neck assembly. Two holes = face up.

Once it's all open, get comfy and begin attempting to thread your new wire. It's hard. I threaded a twisted pair of wires I scavenged from some spare ethernet cable I had laying around. The thinner the better, cuz it's a tight fit.

I started out by pushing the pair up through the bottom, and grabbing it with a pair of needle-nosed pliers and pulling them through. (again, sorry no pictures of this, I was still cooling off from my state of rage) That was pretty easy. Getting them through the top was a pain though.

First, unscrew the three screws.

Top View
Once the three screws are out, you can pull the end bit up, away from the neck to make it easier to thread the wires. (as much as I tried, I couldn't get it to actually come off, which is too bad because that would have made life easier, but oh well.) So take the new wires and push them down the hole where the other wires are going and pull them out with a pair of pliers.

Bottom View
Keeping the end bit separated from the neck as much as possible, bring the wire around and push it through the back. After trying a few (hundred) times, I finally got it. Pull the excess wire through and make sure it curls up nicely next to the other wires.

Then just snap the top bit back in place, re-screw the screws, put the neck back together and you're ready to get your solder on. However, I'm done for the day, but stay tuned for the exciting conclusion.

Keep in mind, this whole wire-threading process took me about an hour and a half. This thing it built to withstand a nuclear blast and there's not a lot of extra room. Good luck. 

Thursday, November 5, 2009

Monitor Replacement: Renaissance

Today went very well. The new LCD Monitor came and when I opened the box I was surprised and very worried. It wasn't the same. HANNS•G model HW173A (old) vs. HB171B (new)

Ignoring the outer shell, the components themselves are quite different. The new boards are linked directly together instead of with a ribbon cable. The monitor controls use a 12 wire ribbon cable instead of the six used by the original which nixes my plan of using one of the iMac's Firewire ports as the outlet for that. The power supply is slightly longer where it meets the video card. And the cable connecting to the monitor is not the same ribbon cable.

However, it turns out all of this is either quite beneficial or easily gotten around. The longer board doesn't seem to pose any problems in terms of fitting into the dome, I should be able to get a simple cable extender for where the two boards connect, the controls ribbon cable... well that really does suck but I'll think of something, and finally, the cable connecting the video card to the monitor saves me a lot of work; it should be super easy to splice it into the iMac's cable that goes through the neck. Ohh and the new one has DVI too which I initially thought would make the card bulkier but doesn't and will provide me with better video quality.

After my epic failure with the last display, I was keen not to make the same mistakes twice. I did a little forensics work on the old panel and it seemed to me like the new panel (which is slightly larger than the old) cracked because of too much pressure along the edges from the metal surround holding it in place.




This is because the metal surround was made for the smaller screen and thus is ribbed to help hold it in place. When the ribs pressed up against the glass panel, they cracked it and coast me $100! Grrrrr




I also wanted to hedge my bets so I'm going to be sporting matching powder free latex gloves and anti-static wrist strap.

With this in mind, I got to work. The steps I went through are the same as in Monitor Replacement Part 1 and Monitor Replacement Part 2.  Here's where we left off:



With the new backlights in place, the newly dremeled black plastic surround is placed back onto the backlight assembly fallowed by the diffusion sheets from the new monitor.



I then placed the LCD panel on top of this and used electrical tape instead of the metal surround to secure it in place on 3 sides. And that's it. I screwed the whole assembly back into the iMac's front bezel and hooked it all up. I must say at this point I was honestly expecting it not to work. However....




IT WORKED!!! Please forgive the poor lighting and all but... it worked!

So tomorrow I'm going to bring the iMac's neck into a Cable company I found on the internet called QCM inc. and see if they'll fasten some connectors to the video cable so it'll easily connect to the monitor's video card. I'm super excited for all this!

Monday, November 2, 2009

Planning Ahead

Well I got a call from the website I ordered the monitor from and long story short is, it's on backorder. So, in the mean time, I've decided to do a little troubleshooting.

Here's where I am right now: Both the LCD's power supply and video board will fit at the top of the dome no problem. There is a .25" gap between the bottom of the power supply and the top of the CD Drive. And leaving me with exactly this much space to work with:


Please, bear with me. There are four posts that connect the top of the dome to it's base. Therefore, nothing can cross those four posts. As this diagram indicates, the motherboard on the Mac mini can't be more than 6" wide, or it won't fit flat inside the base. If it won't fit flat, then I have no choice but to nix the CD drive (then again, it might just nix itself in a minute here). I've looked around online a little and couldn't find anybody who had listed the actual dimensions of the mini's motherboard. The best I could tell from looking at some high resolution pictures I found is that it might just come in at 6" so Hopefully that's taken care of. 

Next, there's the mini's power supply. I really wan't to get this inside, but I'm just not sure how it's going to happen with the CD drive. From what I can from pictures online (again, nobody measures these things...), It looks to be about 6.5" tall, a little over 2" wide, and something over 1" deep. Bottom line is I really don't think it's all going to fit in there with the massive desktop sized CD drive. On the down side, that really sucks. On the bright side, who uses optical drives anymore? That just freed me up more than 60 cubic inches of space that I can use for all kinds of fantastic things! Like getting those proprietary powered sphere speakers to work!

Well, it's true what they say, it's very difficult to fit a square peg in a round hole.

Saturday, October 31, 2009

When Life Gives You Lemons: LCD Edition

The only benefit I can see that came from my little upset yesterday is that I am now able to do a little experimenting. I have first decided to test the backlight dimming theory. The ideas is, as stated a few days ago, that if you lengthen the wires from the power inverted to the LCD backlights, the extra resistance will cause the light to be dimmer. 

So using some extra cat5 cable I had, I soldered in an extension just short of 3 feet. My results: Hard to tell. In the process of doing something, I managed to kill one of the backlights. However, the remaining backlight was still producing a decent quantity of light. It's difficult to judge if it was dimmer or by how much, but it definitely seemed close. So that remains a viable option anyway.

There has also been another development. For the iMac, Apple designed a special, standalone inverter which sits right next to the display. It was suggested that if I could figure out how to use that one instead of the built-in one on the new LCD's power supply, I wouldn't have to worry about cable length. It turns out that might just work.

As seen in the picture below. The iMac's special inverter has a 6 wire "power cable" coming out of it. On the new LCD's power supply, where all the rest of the inverter circuitry seems to be located, there's that big black square thingy which has, at the front of it, 6 beefy solder connections to the board. My theory is, if I pulled that piece out and soldered in six wires in its place, I could run that from the power supply to the iMac's special inverter be home free.



The only problem is, I have no idea which way to orient the wires. Even if you make the giant assumption the wires are in the same order, if I hook it up backwards (the red wire at the top when it's suppose to be at the bottom), I'd probably fry the inverter if not the entire power supply. I'll soon have a backup power supply, but only one inverter...

By the way, here's the code printed on the top of the black square thingy. I googled in but didn't find anything. It's unclear whether the 0 is a zero or the letter. I tried both but neither came up with anything.

SPW-095
LSE r15Ch

If only I had won the lottery, I could just buy up a pickup load of LCDs and iMacs and not have to worry too much about the whole screw up thing. if only...

Friday, October 30, 2009

Monitor Replacement Part 3 - Devastating Failure




There it is.... Well, the backlights worked at least, right?

Anyway I set the LCD matrix in the housing (went to lowe's and called local electronics shop and nobody had heard of that double sided tape so I gave up on it) and put the metal surround back on. Used a little electrical tape to secure everything and went for a test run.

I think the worst part about this is I had the monitor face down on my desk when I first turned it on. When I saw the backlights come... never mind. Needless to say, I'm super down about this.


I have no idea what happened here. The screen obviously cracked in a few places, but that's not what's causing the blue. I've seen tons of people drop their laptops, completely shattering the LCD but there are still portions of different colors and usually have small portions that still accurately map. Not just blue. It doesn't seem to be a problem with the connection to my laptop either (Aluminum 13" MacBook) because the monitor's built in menus weren't working either.

The monitor is no longer on sale at Staples.com but I was able to find it for $107 at PCconnection with free shipping so hopefully it will arrive sometime next week.

Thursday, October 29, 2009

Monitor Replacement Part 2

Spent $45 on the way home from school today to get a shiny new Dremel. I find it interesting that the cheapest Dremel you can buy (at Lowe's) is cordless. The cheapest corded versions started at $70. More powerful motors I guess...

Anyway, got back and took those tabs off in no time. (Don't judge, it's been a while since I've used a Dremel)

Now, there are more different tabs that need to be removed. When I put the diffusion screens from the new monitor onto the iMac's backlight assembly and tried to put the black plastic surround back on, I noticed these diffusers have tabs sticking out in places that the iMac's diffusers don't. I considered just using the iMac's diffusers but upon closer inspection, they one of the layers looked much different so I figure it's best to stick with what was made for the LCD matrix. So I just grabbed a pair of nice scissors and cut 'em right off clean and pretty like. And you're like, that's what she said!

Once everything was all happy with the diffusers, I decided to test-fit the LCD matrix. Too bad it was too big. And you're like... sorry, I'm very tired But seriously, the LCD matrix of the new display was a few millimeters bigger than the one that was installed in the iMac. To add insult to injury, the ribbon cables connecting the LCD matrix to its circuit board is a few millimeters shorter than the iMac's. Yuck. I'll save you the hours of thought process and trial and error that went into figuring this out and get right to it (lucky you!):

So you can't see it in this picture naturally so I've taken the liberty to draw on the track that the LCD matrix fits within. Now the bits on the left are what's in the way. There's stuff in the way on the top to but don't worry, we'll talk about that later. The track along the bottom is (I figure) critical for the LCD to rest on and along the right, the plastic is too thin and cutting the entire track would probably end up breaking it. So I used my Dremel to bring the track down to the surface level.


With the left side out of the way, we can tackle the next problem: the ribbon cables being too short. My solution for this was to completely cut the top of the black plastic surround. I was surprised it actually seemed to free up just enough room and at the same time, still managed to stay firmly connected to the assembly all by itself.

Things to note from the photo above:

  1. When I cut the top off, I left the top corner intact. There is a tab/snap combo that is the key to the black plastic surround not needing any glue to stay on.
  2. Taking the top off the black plastic surround left the aluminum from the backlight lamps exposed. I wasn't sure if that was a good thing or not, so I just covered it with a strip of electrical tape. This has the added benefit of covering and smoothing out my shoddy Dremel job of the tabs on the top at the beginning of this post. 
I test fit the panel and everything seemed to work out. I'm going to wait to install it completely until I can get my hands on some of the double sided tape that was originally used on the black plastic surround to keep the LCD Matrix from sliding around.

Monitor Replacement Part 1

Alright, so I lied. I ripped that iMac to shreds last night. Heres how it all went down:

Note: I'm not going to go over how to dismantle the iMac base or the monitor. Apple's own repair guides are very good, and it's all pretty straight forward. 

So after cracking open the iMac's monitor, I realized there is one minor issues: the new LCD won't fit. The casing on the iMac's panel is, of course, especially designed for the case.

After removing the iMac's Panel and placing in the new one, I noticed that the screw holes that hold the iMac's panel to it's housing are in the way the new panel. I thought about using a Dremel to take them out but that would probably destroy the case.

So instead, I transplanted the new panel into the case of the iMac's panel. This is wasn't really hard, it was just very time consuming and one mishap means I need to buy a new $100 monitor which I would not be happy about. Luckily, it will be quite some time before I'm even able to test to see if this part of the mod worked and by then, there will be so many more things that could catastrophically gone wrong, it won't really matter.

Start by breaking the aluminum colored tape wherever it is present on the iMac's display.

Then, carefully unsnap the tabs that go all the way around the iMac's display and remove the metal surround.


Next de-tab and remove the black plastic surround

Remove the plastic that covers the circuit boards on the back, unscrew the screws holding the boards in place and carefully peel them back. (Fun Fact: I'm just going to stop saying "carefully" and "be careful" now because I don't like to nag (yes I do). Just promise me you'll be careful.)





Now the white plastic bit should just lift right off. There are a few sheets of plastic (diffusers and polarizers I believe) in between the two pieces so make sure you don't let any of them get away from you. I also feel it appropriate to note that it was this step when I had on of those "what the ef am I doing?" moments. Reminding me of this talk Mythbuster's Adam Savage gave regarding failure and these moments. It's worth a watch. 

Now here's where the two roads diverge in the woods. If you were happy with the brightness of your iMac's screen, you can probably try to leave the backlights in, saving yourself loads of work. However, if your screen was dim or non functional (like mine), you're going to need to swap the backlights from the iMac with the backlights (above) from your replacement monitor.

The backlights are pretty easy to remove from the iMac. Just push the exposed ends (where the wires are coming out) up and out of the case.


Once you have them both out, set everything aside and begin to dismantle your new monitor. The process is very similar to the iMac's, but screws are in different places and the tabs/snaps are slightly different. Once you've gotten the casing off of the panel, the actual LCD matrix is completely unprotected so I lay it down on some very soft cotton fabric to prevent any scratching. Yes, those are clean underwear, don't judge me! 


Now the backlight assembly on the new monitor is much easier to take apart than the one on the iMac (you can actually easily pull out the piece of Plexiglas. When I tried to do that on the iMac, I broke one of the tabs holding it in). This is a good thing because you'll need to take the whole thing (Plexiglass and lamps) out of the plastic case in order to get the lamps out.

Take off the last plastic surround by de-tabing it from the back and cutting the tape on the front.


As illustrated below, the backlight lamp is itself different on the new display than the iMac. Because it's so much longer on the back side, it won't fit into the iMac assembly and needs to be trimmed.

Because the lamp's shell is made of aluminum, it's pretty hard to just cut it. There are probably about a million better ways to do this, but I had limited supplies and it was getting late so I used a utility knife to score the cutline (making several passes to get a good dent in the aluminum) and a pair of pliers to twist it off. Make sure you cut enough off the back. If you leave too much, it won't slide all the way into it's new housing.

Once the new Backlights are ready, slide them into the iMac's backlight assembly from the side. I found this to be pretty difficult. Like I said before it would be easier if you could remove the Plexiglass, but when I tried, I broke one of the tabs.

When I got to this point, I was very excited to reassemble the whole thing. But not so fast. Turns out the ribbon cables that connect the circuit boards to the LCD matrix are located in different areas on the new display than they are on the iMac's display. Because of this, almost all of the tabs along the top of the white container are in the way and need to be removed.

After working on this for a while with my utility knife, I was getting nowhere. It was late, I was exhausted, and so I stopped for the night. I'm going to go buy a Dremel tool this afternoon which will make quick work of it and I will probably appreciate having as the project progresses.