Instructables
I found an LCD flatscreen monitor on the sidewalk. Took it back to the lab, turned out the screen was pretty dark, especially on the bottom half, so I figured the backlight was broken. I opened it up and found this to be true. turns out one of the two outputs of the power inverter that fed the two backlights was broken. I had a set of CCFT lamps + inverter ($15--> http://www.allelectronics.com/cgi-bin/item/FL-122WH/search/SET_OF_2_CCFT_LAMPS_(WHITE)_W_INVERTER_.html) lying around from a previous project (lighting a sound proof temperature controlled experimental box) so I decided to pop one in. Here's how I did it (it worked great).

Step 1: Open it up carefully

FIRST OF ALL, BE VERY CAREFUL, THE CCFT LAMPS CONTAIN MERCURY GAS WHICH IS VERY POISONOUS. I take no responsibility if you are in any way injured by mercury gas or any other procedure described in this instructable. To be safe you should do this outdoors or in a very well ventilated area in case the lamps break.

having said that, open the monitor carefully. There will probably be at least two or three weird overlapping wire connections (see picture) which you'll have to carefully unplug to get everything apart. Inside you'll find the LCD screen, a thick glass/plastic light diffusion panel, some thin plastic light diffusion sheets, and two CCFT (cold cathode flourescent lamps)backlights (at the top and bottom of the LCD screen).

Figure out which lamp doesn't work. This may be because the lamp itself is dead, or because an inverter output is dead (the lamps use AC which is converted via an inverter from the DC sent to the monitor). These lamps take high voltages, if you plug in the monitor to figure out if the lamp is broken be careful.
 
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IronManMC2 years ago

I'm an electronics engineer. I've spent 5 hours repairing a $3 transistor radio many times. It's not the money (well, not always). It's a challenge, a game. And when I go through the radio (or??), I make improvements. First, I "bullet proof" (replace/modify parts/circuits most likely to fail). I'll replace an IF transformer with a ceramic filter, improving selectivity and fidelity. I use larger interstage caps and rebias sections that are distorting. I might add a 3 watt mono class D power amp, power it with D cells or a 6 volt 7 amp hour gel cell, add a charging circuit that won't fry the battery, and mount it all inside a nice speaker cab. I *hate* those little tiny tuning wheels and usually replace them with vernier knobs. These are very accurate, and eliminate the need for digital displays. I snap up vernier dials for pennies on the dollar at ham swap meets, estate sales, and such. Some of these are 30:1, and built like They're too expensive (new) for consumer gear. They're fairly routine on lab gear and military electronics. I *LOVE* JAN (joint Army-Navy) and MIL SPEC surplus.
beowolf6 years ago
I have an old Gateway FPD1800 flatscreen momitor (circa 2000) that doesn't seem to work when I give it power and turn it on. I can see the green power light turn on then it quickly turns into a somewhat yellow color. But nothing is happening on the screen. the "no signal"/ "loss of signal" window doesn't even show, the screen is just black. Can anyone possibly tell me what is wrong with my monitor? Please excuse the unprofessional style of the following pics.
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Did you ever figure out a way to repair the gateway monitor that was going to sleep. I have an Acer CRT monitor that is doing the same thing , green led , then it goes back to sleep (orange)  like there is nothing connected to it. The connector is fine, the VGA card works flawlessly , and the Hz signal is within monitor specs so ? what could it be?.

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legless beowolf6 years ago
It sounds like the power supply is going into power saving mode (like standby mode) and won't come out. I have one with the exact same problem that some time or another I will fix.
is there anyway to stop  a moniter going to standby when theres no input signal ? i have a bust moniter and am wanting to use the backlight ( i cant seperate the inverter from the mainboard cause i cant figure out the 4 wires to make it work 12v . any suggestions would be great because its been on the workbench for a week and its doing my box in . thanks
If it is the inverter and you definitely can't fix it or find it, you can buy a suitable inverter board on ebay fairly cheaply if need be. I will have a go at repairing my inverter but still had no chance to do it. It's quite often a separate small circuit board. Usually obvious as it is connected to the backlight not the LCD panel.
Lynstef legless5 years ago
hi legless when you fix your monitor could you please do it as an instructable as my monitor is behaving exactly like you described. Hopefully you'll feel like having a go in the very near future. Thanks! regards Lyn
Have you tried a new adapter? There are lots at <a href="http://www.12vadapters.com">12V Power Supply</a>.
Take a look at the instructable I just posted, pretty similar, if you read the steps I tell how you can check the screen with a flashlight

http://www.instructables.com/id/Replace-LCD-Backlight-Inverter-on-Any-Monitor-for--
bwpatton14 years ago
ohh nooo!! Tell me thats not a viewsonic!!! I have one exactly like that, with a burned out inverter!!!
Hmm I may try this.....
xenoalien7 years ago
Do all LCDs contain a lamp?
leevonk (author)  xenoalien7 years ago
all LCD monitors, yes. Even on palm pilots and cellphones.
jongscx leevonk6 years ago
Not necessarily. At least not Cold-Cathode Lamps. Recently, they have been moving to LED backlights. small appliances (cell phones, PDAs) especially...
cyrozap jongscx5 years ago
And Apple's new LED cinema display.
a lo of laptops especialy netbooks are led nowdays
baneat5 years ago
i'm not screwing around with mercury gas to save a buck.
ironsmiter6 years ago
just curious, why not tap the power source from the burned out backlight, for your 12V source to run the inverter?
leevonk (author)  ironsmiter6 years ago
it's funner my way :)
Cool Stuff! Well done!
PetervG8 years ago
Why would someone throw out a LCD flatscreen monitor. I'm sure someone would repair it for them and then they could do somthing with it?!
Why? Because you now live in a "throw-away & Recyclable" society. Even your cars are made to be recycled with aluminum engine blocks to melt down. Plus some people out there just have enough money to spend on new stuff instead of using their brain to improvise, which makes us even happier.
n0ukf PikesPeak7 years ago
Recyclable? Come on, most people forget about recycling when it comes to electronics. Nokia however has a phone recycling program (I just found that out last month), my latest Tracfone came with a postage-paid envelope for this. I found a free scanner at a yard sale and replaced the broken CCFT with a $3 one from All Electronics and it worked fine.
Don't forget the repair principle! If it will cost less than 1/3 of the price to buy a new one to fix it: Fix it If it will cost more: Don't "Price" Includes monetary value ($$$) and time. That is just something that people tend to follow. Personally, if I'd save a nickel, I'd do it.
leevonk (author)  PetervG8 years ago
all kinds of wonderful stuff is thrown out in new york city. This was outside of a business, so they had enough money to just get rid of it. It would have cost a lot to have it fixed (would have needed a new inverter), and they have to run a business so they can't go for a week without a monitor.
robodud37 years ago
how much could i sell one for on ebay if i called it "refurbished" cuz i need $600 for an iphone by june
jeasterl8 years ago
think it could be rewired for a string of high brightness white LEDs (tougher and not likely to burn out anytime too soon)
leevonk (author)  jeasterl8 years ago
yeah, any number of things would work. initially I was planning on just cutting off pieces of the back of the case and putting a lamp behind the monitor. It's hard to do that though because there are electronics in a big box right behind the lcd.
mikesty8 years ago
COOL! FYI, i think you can either sand down, file off, or yank off those knobs on the end of the CC.
leevonk (author)  mikesty8 years ago
yeah, but I'm paranoid, I prefered to leave the protective enclosure around the CCFT, expecially considering that it wasn't really secured very well in the case (although that could be done pretty easily).
trebuchet038 years ago