Samsung 2493HM Repair: Burnt Out Resistor

[Matthew_F]

Hey guys!

So I woke up the other day to a black screen and a blue power light on. I poped the sucker open expecting some caps to have died, but found a burnt out resistor hole.

I'm a complete novice.

A few question. Is a burnt out resistor ever caused by other components dying? Or just mostly self failure?

It appears the circuit ring on the board was also burned out with a small bit of the copper trace left. What's the best way to handle this during replacement?

I've attached 7 pictures to IMGUR:
http://imgur.com/a/qW8d8

Lots of appreciation.
Matt

[Agent24]

Re: Samsung 2493HM Repair: Burnt Out Resistor

I think I've seen that model on here before.. The photos look familiar. The problem is that shitty brown glue. It becomes conductive over time and shorts things out.

For a start, you'll need to remove all that glue and clean up the burnt areas so there is no more arcing. Replace any burnt components. You may need to replace some other parts too.

Also please attach your photos to your posts (you can upload them to this website when you post) as it makes it easier for us, and keeps them around for future reference.

[re-atari]

Re: Samsung 2493HM Repair: Burnt Out Resistor

The problem is that shitty brown glue. It becomes conductive over time and shorts things out.

And the glue corrodes the metal parts of the components covered by it.

For a start, you'll need to remove all that glue and clean up the burnt areas so there is no more arcing. Replace any burnt components. You may need to replace some other parts too.

I´d replace all components that were originally covered by this brown goop. Chances are they are corroded anyway, which makes them unreliable in the long term. Check the FET´s with your multimeter for shorts, it´s likely they didn´t survive the accident without battlescars.
It looks to me you can bridge the traces that are burned away with a piece of wire. Just replace the original 2 wires with longer ones, and use the excess wire to bridge the gaps on the solder side.

re-atari

[Matthew_F]

Re: Samsung 2493HM Repair: Burnt Out Resistor

Okay, great. What's the best way to remove the glue safely without damaging parts? Should I use Isopropypl to help? I'm chiseling out the glue right now. There seems to be multiple areas that are beginning to char.

Here is the resistor that burned through the hole.
http://imgur.com/yqK7Jsn

What would be a viable replacement for this little sucker? Would radioshack have it?

I haven't done any type of electrical work in many years so I'm very rusty on terms and labeling.

Thanks for your help guys.

[re-atari]

Re: Samsung 2493HM Repair: Burnt Out Resistor

Okay, great. What's the best way to remove the glue safely without damaging parts? Should I use Isopropypl to help? I'm chiseling out the glue right now. There seems to be multiple areas that are beginning to char.

I always take a small flat plier and squeeze the glue untill it breaks away. On your board it looks quite crusty, so will probably just desintegrate in flakes. Do make sure you remove all residu on the board itself, I use a small flat screwdriver to scrape it off. As I said, replace all components that were covered in this stuff.

Here is the resistor that burned through the hole.
http://imgur.com/yqK7Jsn

What would be a viable replacement for this little sucker? Would radioshack have it?

That's a ceramic capacitor, 47pF rated for 1000 Volts. I doubt Radioshack will have it, but Mouser or Digikey probably do.

re-atari

[Matthew_F]

Re: Samsung 2493HM Repair: Burnt Out Resistor

I'm having trouble figuring out a few of the color stripes on these resistors that I should probably replace. Is it possible to find the original layout of the board and just look up the specs of each of the components? Like a PDF.

Thanks

[Agent24]

Re: Samsung 2493HM Repair: Burnt Out Resistor

This may be what you need: http://elektrotanya.com/samsung_2493.../download.html

[re-atari]

Re: Samsung 2493HM Repair: Burnt Out Resistor

I'm having trouble figuring out a few of the color stripes on these resistors that I should probably replace. Is it possible to find the original layout of the board and just look up the specs of each of the components? Like a PDF.

Thanks

Insiders info: there are already more than a few threads on this forum dealing with this particular PSU, as it´s also used in Samsung 245B monitors. Do a search on this type or on BN44-00195A (the PSU mfg'er nr.), and you'll find lots of information.

re-atari