Samsung le19r86wdx - Noise

[mcfly666]

Re: Samsung le19r86wdx - Noise

^^ Thanks a lot for your help Tom, I think that I will swap the part around from the two boards for now and see if it changes the noise at all.

Looking at the two boards, the part in question has no markings for positive and they are soldered on the board in opposite ways.

What i mean by that is on one board the writing is facing the large 450v capacitor and on the other the writing is pointing away from the cap.

I suppose it does not matter which way round the small cap (C 106) is soldered?

[tom66]

Re: Samsung le19r86wdx - Noise

It is nonpolar, so it can go any way.

As I said swapping them over may well do nothing if both boards have the same fault.

[mcfly666]

Re: Samsung le19r86wdx - Noise

^^ Hi again Tom, I had nothing to loose and swapped it over before dinner cant really tell if it produced a change or not, though I don't think the sound is coming from there (hard to say with high frequency sounds)

From what I can gather there is a noise coming from the transformer area and there is another noise coming from the area below. The noise from the transformer at the moment is bearable. Though the noise coming from the area below is the "kettle coming to a boil" noise and it quite often changes pitch (not related to screen settings) Could it be coil whine from the inductor?

Might have to bite the bullet and get a new board, though it would be grand if I can keep this one away from the scrapyard.

[tom66]

Re: Samsung le19r86wdx - Noise

Could be that component, triedusing some kind of varnish or epoxy on it?

[Kilroys]

Re: Samsung le19r86wdx - Noise

Dont change it to another blue 1000pF. Try another type.
There are gray, brown caps.
Guess it goes into resonance with the transformer.
Perhaps exactly 1.000 pF on this cap, while another
type could be 10% up or down.

[mcfly666]

Re: Samsung le19r86wdx - Noise

Well, just to try I swapped the inductor over. no change. But as you said Tom the board could have the same fault.

I could try using some epoxy on it, not got varnish. Will the epoxy be ok for heat?

[mcfly666]

Re: Samsung le19r86wdx - Noise

Dont change it to another blue 1000pF. Try another type.
There are gray, brown caps.
Guess it goes into resonance with the transformer.
Perhaps exactly 1.000 pF on this cap, while another
type could be 10% up or down.

Sounds good mate, thanks for saying

On another note i've been looking at some later revision boards and apart from having different caps there are two big changes..

Ether side of the inductor there are two yellow boxes and they have been changed to blue one in the later revisions. It might be clutching at straws but it does seem to be in the area of noise.

I wonder what those boxes are and if they could make a whining noise?

[tom66]

Re: Samsung le19r86wdx - Noise

They are probably capacitors and the colour likely indicates a different manufacturer made them because they were more able to supply the parts, were cheaper, etc. It's probably not a design change.

[mcfly666]

Re: Samsung le19r86wdx - Noise

Thanks Tom66 - I'm going to see if I can get a known good board from Ebay Do you know if I will have any problems using a newer revision board like we would have got if I used the newer rev board on the plasma we fixed?

Plasma is still going btw

[tom66]

Re: Samsung le19r86wdx - Noise

I think any rev board will work if connectors and mount points are the same. Good to hear about the plasma I am tackling a newer LG plasma now, boy how little there is in these new plasmas!