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dwtt
10-07-2009, 5:01 PM
I figured since this involves analog circuitry, it may fall within the technology realm of this forum. :) Well, our TV of 21 months died and it was the power supply board. The company wants $130 for a new board but I tried looking up the schematics for the board with no luck. This board, it turns out, is a purchased item and also used in Viewsonic lcd TV's, so I'm hoping someone here might be able to point me in the proper direction to getting the schematics for the board. I don't know the manufacturer, just the model number on the board, FSP271-5F01

I would much prefer to replace a $1 or $5 part on the board than buy a whole power supply board for $130.
Thanks everyone.

lazyworm
10-07-2009, 8:41 PM
I'd think the schematic is propriety. Unless you're experienced with circuit
boards, I'd think it'd take quite a while to troubleshoot it. How much is
a couple hours of your time worth?

a quick search showed you can probably find it cheaper online.
e.g. http://www.google.com/products?q=FSP271-5F01&oe=utf-8&hl=en&scoring=p

Gunaria
10-07-2009, 9:49 PM
IIRC if there is a FCC ID# on the board you can go to some .gov site and look up who the OEM is. Use the power of the google. I used to have it bookmarked long ago.

phish
10-07-2009, 10:41 PM
It could be more trouble than it's worth. PCBs are so f'n densely packed these days with the majority of the components being smt. If you have access to a DC power supply, o-scope, DMM and time to spare, by all means...

I doubt it's a busted cap, in all my years of troubleshooting PCBs, it was never an obvious thing such as a busted cap.

Corbin Dallas
10-09-2009, 7:00 AM
It could be more trouble than it's worth. PCBs are so f'n densely packed these days with the majority of the components being smt. If you have access to a DC power supply, o-scope, DMM and time to spare, by all means...

I doubt it's a busted cap, in all my years of troubleshooting PCBs, it was never an obvious thing such as a busted cap.

Exactly, and not only that, most PCB's are multi layered (6 or more) internally. If any one of these traces is the cause of your problem you have to replace the entire PCB anyways.

I think you'd be better off getting a new PS board.

GrizzlyGuy
10-09-2009, 7:54 AM
Here is the same PS unit for $70:

http://cgi.ebay.com.my/Viewsonic-POWER-SUPPLY-UNIT-FSP271-5F01-N3752W-LCD-TV_W0QQcmdZViewItemQQitemZ110290002106

Other than maybe trying to reflow the solder joints on the old board and hoping that fixes it (unlikely) I think your best option is to replace it.

JDay
10-09-2009, 6:52 PM
Here is the same PS unit for $70:

http://cgi.ebay.com.my/Viewsonic-POWER-SUPPLY-UNIT-FSP271-5F01-N3752W-LCD-TV_W0QQcmdZViewItemQQitemZ110290002106

Other than maybe trying to reflow the solder joints on the old board and hoping that fixes it (unlikely) I think your best option is to replace it.

Did you look at the postage on that? $47.99!

Gunaria
10-10-2009, 1:23 AM
Did you look at the postage on that? $47.99!

That's about as much as a long gun from some GB dealers.

GrizzlyGuy
10-10-2009, 7:33 AM
Did you look at the postage on that? $47.99!

Holy crap! No, I didn't see that.

dwtt
10-10-2009, 8:27 AM
I looked at the board and the component density is very low since it's a power supply board. I ended up paying the company for a new board instead of spending the time to trace out the circuit. The board is not multilayer and only double sided, so it's pretty straight forward, but the thing still costs a lot. Must be those expensive transformers. :(

I didn't think the supplier would sell me the schematic and I had no luck finding it on the web or any online sellers.