Samsung le19r86wdx - Noise

[mcfly666]

Hi,

I have my GF's Samsung le19r86wdx LCD here. A strange high pitched sound is being emitted by what I think is the powerboard.

It's been like that for ages and has never had a fault apart from the sound, but the other half will not use the set for fear of it blowing up...

Is there anything I can do to stop the sound, I have tried isolating it by way of a stick in order to see if anything was vibrating but nothing.

Thanks in advance people.

[mcfly666]

Re: Samsung le19r86wdx - Noise

I have had a further look at the set and noticed that some caps are a little strange, slightly raised. Though I don't know if they could be cause for the 'noise'

On one picture the caps are identified by a red circle.

Any thoughts?

[Dang]

Re: Samsung le19r86wdx - Noise

Yep, definitely caps, simply change like for like and all should be fine.

[vinceroger69]

Re: Samsung le19r86wdx - Noise

i would change all the capacitors on that board except the very large one as there usually ok i only see 7 or 8 i use cpc farnell at the moment free delivery and no minimum order use panasonic fc fm fr capacitors in my opinion.

[mcfly666]

Re: Samsung le19r86wdx - Noise

Yep, definitely caps, simply change like for like and all should be fine.

Hi, Thanks for confirming. It's a great help!

i would change all the capacitors on that board except the very large one as there usually ok i only see 7 or 8 i use cpc farnell at the moment free delivery and no minimum order use panasonic fc fm fr capacitors in my opinion.

Hi, I am a little confused. The FC, FM, FR you said about, are they just the quality of the caps or do they hold some other value to the running of the set?

I am going to order FC series caps from CPC. As long as the voltage and microfarad's are the same everything is OK?

Thanks for your help!

[tom66]

Re: Samsung le19r86wdx - Noise

FC = Very good
FM = Even better
FR = Best

"Very good" is still fine!

[mcfly666]

Re: Samsung le19r86wdx - Noise

Thanks for the help Tom66, parts are all ordered and I will update the thread when I get the TV back together.

Much thanks!

[mcfly666]

Re: Samsung le19r86wdx - Noise

Ok, so the caps came from CPC this morning (superb delivery time) After replacing the suspect caps the TV still makes a noise.

I don't think the noise was as bad as it was, however it's still too noisy for the other half.

Anyway the noise is coming from the component marked WD-17, the noise is a whistle and i can only describe it as an "old kettle coming to boil"

Any thoughts, Is it work replacing the other caps as previously advised or could the out of spec caps damaged component WD-17?

Thanks guys.

[tom66]

Re: Samsung le19r86wdx - Noise

It's a transformer. They use varnish in them to stop the windings vibrating and producing a noise. You can try taking the tape off the top and using glue on the windings. Sometimes the varnish dries off and it begins making noise.

[mcfly666]

Re: Samsung le19r86wdx - Noise

Thanks Tom,

Just had a look and the tape on the top seems to have a plastic 'lid' underneath. Not sure if I take it off I will get access to the coils.

Tape on the sides seems to have been heat treated to melt into the coils, if i try to take that off I'll probable damage it. Or am I missing a trick?

How hot do these things get tom? I am contemplating putting a layer of silicone round to see if that would dampen the noise, but not if there would be a fire risk.

[Alastair E]

Re: Samsung le19r86wdx - Noise

Ive had the Backlight Board caps fail--and make the PSU make buzzing noises on one set--Cant remember the make at the mo....

Worth just checking out the caps on your B.L board....

Edit--Scrub that, you dont have a BL board....
--Its a combined board with PSU....

[tn245]

Re: Samsung le19r86wdx - Noise

I had an LG that was squeeling even when in standby. I think it was tom66 suggested I use varnish on the offending transformer (remove the transformer first obviously). I think there's special varnish you're supposed to use and techniques involving a vacuum pump in order to get the varnish right into the windings, but I literally just dipped it into some quick drying wood varnish. I heard you need to make sure it's totally dry so I dried it out in a low oven first then submersed it in the varnish hoping it would penetrate as much as possible. After the varnish dried I reinstalled it and amazingly it did quieten the transformer to the point it's only audible if you're trying to listen for it.

[mcfly666]

Re: Samsung le19r86wdx - Noise

Hmm Food for thought.

Would cooking the transformer in the oven @200c have any benefit, or would it destroy the transformer? or even better is there a place that would supply the transformer?

[tn245]

Re: Samsung le19r86wdx - Noise

Hmm Food for thought.

Would cooking the transformer in the oven @200c have any benefit, or would it destroy the transformer? or even better is there a place that would supply the transformer?

I suspect some parts may be plastic and would probably melt. Not sure what you're hoping to achieve by cooking it. I only put it in around 50-70C I think and that was just on someone's suggestion to dry it out before applying varnish. Also, as it cools it's supposed to pull the varnish in. Worked for me. Worth a try before looking for a replacement don't you think?

[mcfly666]

Re: Samsung le19r86wdx - Noise

Just cooked it, I thought the heat wrapping of the tape might have melted and quieten down the coils. I don't have any varnish to hand which is a bummer.

On the bright side I didn't kill the transformer and it still works, I'm afraid I'll have to bite the bullet and source another transformer or board (quite likely not to too far off the cost of a pot of varnish @ bnq)

I'll have a phone around and see if i can liberate some.

Thanks

[vinceroger69]

Re: Samsung le19r86wdx - Noise

you need electronics varnish like this really shop around for best price imo
http://uk.rs-online.com/web/p/produc...Fafnwgod_zkAYQ

[mcfly666]

Re: Samsung le19r86wdx - Noise

OK, strange turn of events. got myself a borked board on the cheap and replaced the transformer over with my noisy old board...

No real change in the noise, the noise still seems to be coming from the transformer - I find it odd that two transformers exhibit the same noise?

Anyway, could there be anything "out of spec" on the board which causes a strange whistling noise?

Cheers in advance.

[Kilroys]

Re: Samsung le19r86wdx - Noise

If the board is bn44-00152b then
change C 106 1000pF 1kV to another type.

[mcfly666]

Re: Samsung le19r86wdx - Noise

If the board is bn44-00152b then
change C 106 1000pF 1kV to another type.

Hi there, thank you for your input.

I think the board is bn44-00152b S/N number is :CN08BN4400152BSE38B5NA193

I located the part described (in front of a large cap) Part is labeled: B 102k 1kv

If that sounds right I have a spare one on the old board or I can buy a new one, problem is I don't know what on earth it is and if I bought a replacement, I wouldn't know whether to get the same spec.

Would it be possible to ask what it is, and is it worth buying a new one or will replacing it with the part from my old board make a difference?

Thank you so much.

[tom66]

Re: Samsung le19r86wdx - Noise

Don't know where Kilroys got the idea from, but I would presume if he means it's making the noise, you'd want to use a new one.

It's a 1nF 1000V polyester capacitor. I have heard them make noise before.

This might work, dimensions might be tight though:
http://cpc.farnell.com/lcr-component...1kv/dp/CA05652

Alternatively:
http://www.ebay.co.uk/sch/i.html?_tr...at=0&_from=R40