About Circuit Board
Not all circuit board are design to be removed easily for testing. Some of the board like the LCD Monitor board have the power IC soldered behind it and this make us difficult to test the signals. Well, you can always remove the board and turn the board but sometimes because of the output wires connection to the Mainboard are short, you will still have problem in testing it. Sometimes, with just a minor fault (accidentally touching on other components due to constraint of space) it may blow up the power board.
In order to solve this problem, what you need to do is to solder external wires to the critical points in the power supply. Just solder the wire to the supply voltage pin and output pin of power IC and you will know if it good or not when testing it with meter and scope. Actually you have the choice to choose whether to do it this way or just directly replace the power IC and check all the components in it, but because you want to understand more about the troubleshooting, i guess you have no other choice other than solder wires in the important points. You may use this method to apply on any boards that the meter probes hard to reach.
GeoNOregon
February 27, 2010 at 1:06 pm
Jestine:
Have you ever tried to fix or even just messed around with a keyboard's insides? They have a very small circuit board, but it's the membrane contacts that are the mystery to most.
My wife has very small hands and works on her computer for a living. I found her a keyboard several years ago and foolishly didn't buy a half dozen of them. They were the only keyboard on the market that has less than the standard .75" center to center distance between keys. Now they are out of business, and I haven't been able to find her a replacement keyboard.
The problem she's having is like there's a 'stuck' key, but the key is not physically stuck. We took it apart and thoroughly cleaned it, hoping that might help, but it didn't. If you have any ideas, suggestions, or even if you'd like to give a go at fixing it, let me know and I'll send it to you - obviously, I'd compensate you if you want to try or can fix it.
Thanks,
GeoD
admin
February 28, 2010 at 1:35 am
HI Geo,
Have you try to find one from Ebay? I suggest that you send to any electronic repair shop in your country to ask if they can repair such keyboard or not. The Membrane type is quite hard to fix.
Jestine
Waleed
February 28, 2010 at 4:02 am
Yes Jestine, I sometimes do that and very very easy to do and very safe. I always thought to my self that this is a not a professional way to do things but I guess I was wrong. thanks for making me feel good.
admin
March 1, 2010 at 1:11 am
HI Waleed,
Thanks for sharing!
Jestine