Samsung PN42C450 Sustain Boards

[rcewilson]

Both The X and Y boards seems to have shorted transistors. Is this common?
If they are unplugged I do get the startup audio sound.

[tom66]

Re: Samsung PN42C450 Sustain Boards

I've seen the X board go so yeah, seems fairly common. These TVs are built right down to the last cent so it's fairly common to get shorted semis on them.

[rcewilson]

Re: Samsung PN42C450 Sustain Boards

I'm trying to figure out if it's worth fooling with. Two boards are bad at least. Would I expect the buffers to be bad also? Or maybe something else I haven't thought of.

[tom66]

Re: Samsung PN42C450 Sustain Boards

I'm trying to figure out if it's worth fooling with. Two boards are bad at least. Would I expect the buffers to be bad also? Or maybe something else I haven't thought of.

You can do a resistance check on the buffers. They might be okay.

[rcewilson]

Re: Samsung PN42C450 Sustain Boards

Can you give me some hints on how to check out the buffer board? I do not have the service manual.

[tom66]

Re: Samsung PN42C450 Sustain Boards

SM for PS42C430 - maybe same/very similar?
http://www.tgohome.com/ServiceManual..._src=AltSearch

Can you please post a picture of your buffer boards.

[rcewilson]

Re: Samsung PN42C450 Sustain Boards

Yes, you are correct. It does look the the 42" model in the manual you listed.

[rcewilson]

Re: Samsung PN42C450 Sustain Boards

Let me clarify that.
In the Samsung_PS42C430_Disassembly & Reassembly_[SM].pdf it looks the same. The buffer board has the three connector near the bottom of the board.
I can still post a picture if needed. Thanks for pointing out this manual.

[tom66]

Re: Samsung PN42C450 Sustain Boards

If possible can you post a closer picture of the buffers so I can highlight where to test for shorts.

[rcewilson]

Re: Samsung PN42C450 Sustain Boards

Here are the pictures.

[electronicsurplus]

Re: Samsung PN42C450 Sustain Boards

On the connector of the buffer you will see 2 of the pins which are separated from the rest on one end (These are positive) and, there are most grouped together (These are grounds) check between these points. In one direction you should get infinite and the other anywhere above 500k using diode check on a multimeter.

If they read anything less then it is shorted (Very common)

[rcewilson]

Re: Samsung PN42C450 Sustain Boards

I don't seem to see this. All three connector have pins that are equally spaced just like the one I photographed.

[tom66]

Re: Samsung PN42C450 Sustain Boards

You need to be looking at the copper traces on the board itself. The lighter green lines.

[rcewilson]

Re: Samsung PN42C450 Sustain Boards

OK maybe the buffer board is bad also. In that case I am giving up on this one as it needs three boards plus I don't have the remote. Just not worth the cost for me. This model built in Oct 2010 must have cut too many corners in trying to be more competitive.
Thanks for your help. I did learn a few things at least. Maybe next time it will turn out better.