$2.50 Computer Monitor
A few weeks ago, I took a look in my school's awesome electronics recycling pile, and found a Samsung SyncMaster 740n 17" monitor there. I assumed something was wrong with it, but a while ago a friend of mine got a similar monitor from the pile and the only thing wrong with it was the VGA cable. So I took it home, and powered it on. The LCD itself worked, but the backlight did not. I opened it up and found that there were 4 cold cathodes inside, and figured it would be fairly unlikely for them all to have died, so I took a look at the power circuitry. And what do I find? This picture should speak for itself:
I searched for the problem, and found a thread dedicated to this issue on Badcaps.net. According to them, there was also a 3A picofuse that usually died along with those 3 capacitors. It is the green thing that can be seen above the first two. I was already planning to make an order from an electronics supplier for switches for my HTPC, and added some new capacitors plus a box of fuses. The original caps were 870uf 25v caps, but the store did not supply those, so I got 2x1000uf and one 470uf to add up to a similar capacitance, which works according to the people on badcaps. Also, the store did not carry the picofuses, so I got a box of 3A glass fuses.
Everything came so I got to work
Caps, with some extra:
The first thing I did was switch out the capacitors:
On testing the monitor again, I still had the same problem, so I then switched the fuse.
Here's the old vs. new:
The new one would not fit where the old would, so I soldered some wires to the bottom of the PCB, and then the fuse to those:
The whole assembly:
Monitor reassembled:
And the moment of truth.....
It works!
Here was the old monitor setup on my desk (excuse the mess)
The monitor on the right is an approximately 10 year old 15" Dell LCD, which amazingly is still working great. Here's the new monitor in place:
Looks much better. The new one has an extremely thin bezel, the colors more closely match my 21.5", and the pixel density is much closer than that of the old screen, which had a resolution of 1024x768, as opposed to the newer's 1280x1024.
Here's a closer look at the split:
There is still some stretching when moving to the smaller screen, but the size is much closer than it was before.
That's it. I'd say I did not do such a bad job, as this was the first time I have done any component level repairs on electronics. In total, this cost me about 2.50 for parts, and around an hour of time to do, which is not a bad price for a monitor in my opinion.
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Originally Posted by Technochicken
so far left of center i'm in right field
