Flickering monitor - Samsung 226BW

[thomas101]

Re: Flickering monitor - Samsung 226BW

I replaced all of the caps include the big one. My monitor still having this weird problem. Please help.

The monitor turn on with a blue light around the power button. When I plug in the computor into the analog on the monitor it display for 2 second then goes to black screen.

Can this be a backlight problem? Please help me fix this monitor

Thanks in advance

[Wrog]

Re: Flickering monitor - Samsung 226BW

I replaced all of the caps include the big one. My monitor still having this weird problem. Please help.

The monitor turn on with a blue light around the power button. When I plug in the computor into the analog on the monitor it display for 2 second then goes to black screen.

Can this be a backlight problem? Please help me fix this monitor

Thanks in advance

There are many, many threads on this type of problem. Search for "two seconds to black" in the Troubleshooting Computer Displays forum for the possible causes and remedies. Post back with any specific questions if you have questions on executing some tests or interpreting some measurements. Posting pics of the top/bottom of each board (power, logic and inverter) using the forum guidelines will probably get you a step further. Above all -- read, read, read and then ask questions.

[Wizard]

Re: Flickering monitor - Samsung 226BW

That's not flicker, flicker is sudden subtle intensity of backlight, that's exact definition of flickering. That's 2 second and out symptom (blanks out). Need to check waveforms of the inverter transformers (if bad, one will be weaker than other) and test the lamps to troubleshoot.

Cheers, Wizard

[thomas101]

Re: Flickering monitor - Samsung 226BW

Hello Wizard and Wrog,

First of all thank you very much for the fast reply. This is my first time trying to fix monitor.

Wizard: Could you please show me how I could check the waveforms of the invertransformer? What tools do i need?

Sorry but I'm news at this, Once again thanks in advance

[BlueSteel]

Re: Flickering monitor - Samsung 226BW

My 226BW (manufactured/bought spring 2007) was also dying since a few months, today the flickering finally went so bad that it would only stop if I set the brightness to 1.

I took the screen to a friend who owns a computer store, and we replaced caps C110-C112 who were already bulging outward. Since we did not have the correct components, we used 1000uF/25V for C110 and C111 (should be 880uF/25V) and replaced C112 with a 470uF/25V instead of 330uF/25V.

For now the screen works perfectly again, but my friend suggested that I should at least replace the 470uF one with the correct one. Does anyone know what could possibly happen while I run it with the 470uF one?

btw, we measured the old caps and the 880uF ones were down to ~120uF while the 330uF one was down to ~180uF

[PlainBill]

Re: Flickering monitor - Samsung 226BW

My 226BW (manufactured/bought spring 2007) was also dying since a few months, today the flickering finally went so bad that it would only stop if I set the brightness to 1.

I took the screen to a friend who owns a computer store, and we replaced caps C110-C112 who were already bulging outward. Since we did not have the correct components, we used 1000uF/25V for C110 and C111 (should be 880uF/25V) and replaced C112 with a 470uF/25V instead of 330uF/25V.

For now the screen works perfectly again, but my friend suggested that I should at least replace the 470uF one with the correct one. Does anyone know what could possibly happen while I run it with the 470uF one?

btw, we measured the old caps and the 880uF ones were down to ~120uF while the 330uF one was down to ~180uF

The most likely result is that it would work perfectly. If your friend used General Purpose caps, not low ESR caps, the higher values may delay the inevitable failure a few months. If he used low ESR caps, there is a very, very slight possibility it might lead to a premature failure of the rectifiers. For a 22" I would order a full set of caps from Digikey. With USPS First Class mail shipping your total cost would be about $10.00.

PlainBill

[BlueSteel]

Re: Flickering monitor - Samsung 226BW

Well, it does indeed work rather nicely right now. I plan on getting a new screen as soon as I can afford one anyway, so as long as this holds a while longer it's ok. I'm not sure what kind of caps we used, we just removed some from an unused replacement PCB for a CRT screen that he had lying around. It was more of an emergency measure than a planned repair.

Thanks for the tip with Digikey, unfortunately the shipping costs to my country would make it rather expensive. But I'll probably change the 470uF capacitor anyway, just to be on the safe side. Unless you think that it should not matter much at all...

[retiredcaps]

Re: Flickering monitor - Samsung 226BW

Well, it does indeed work rather nicely right now. I plan on getting a new screen as soon as I can afford one anyway, so as long as this holds a while longer it's ok. I'm not sure what kind of caps we used, we just removed some from an unused replacement PCB for a CRT screen that he had lying around. It was more of an emergency measure than a planned repair.

Thanks for the tip with Digikey, unfortunately the shipping costs to my country would make it rather expensive.

Reusing old caps is good for testing, but you should get new low ESR caps all around from manufacturers like Rubycon, Panasonic, and/or United Chemicon.

This monitor is only 3 years old and should last a few more with new caps.

What country to you live in? When newbies sign up they are not prompted for their country so we always assume North America until told otherwise.

[BlueSteel]

Re: Flickering monitor - Samsung 226BW

I'm living in Sweden right now, so I guess I should try finding a place that sells quality caps around here. You are of course right that the monitor should hold longer than three years, but I am also a little bit afraid that it will break completely when we replace the caps again.

The caps we used were new (as in never used) since that replacement PCB where we got them from was never actually built into anything. But the quality of the caps is probably not exactly stellar, so ordering a full set and replacing everything might indeed be the best idea. I'll have a look around for a good electronics store.

[digge]

Re: Flickering monitor - Samsung 226BW

If youre in Sweden you could try elfa (www.elfa.se) or electrokit (www.electrokit.se) or bihab (www.bihab.se)

There are more of them, just the ones of the top of my head. Elfa at least carries Sanyo wich are at least half descent. Electrokit have some Nichicon and Rubycon models.

[Wreckless]

Re: Flickering monitor - Samsung 226BW

would you believe it i got up toay and switched on my syncmaster226BM and it now has a strobe introduction lucky for me i am a service tech with some electronics knowlage.
came here to find all the hard work had been done for me
i am based in the uk and noted items needed off i went to RS Comonents site to order my parts.
if you are in the uk and know of RS Components then this may help you.
RS partnumbers for what you want sadly as std they only come in packs of 5,
they are the panasonic ones and have same EEU numbers stated earlier in this post.
47uf 50v 105 °C 572-198
820uf 25v 105 °C 526-1571
330uf 25v 105 °C 526-1519
680uf 25v 105 °C 526-1569
total cost £8.66
will post how it goes once done

[Wreckless]

Re: Flickering monitor - Samsung 226BW

seems there where only 3 bad ones so i replaced them
c10 330uf c11 820uf c12 820uf all 25v
screens seem ok for now
thanks again for all that posted here to make my life so easy

[Scenic]

Re: Flickering monitor - Samsung 226BW

bad idea to only replace the obviously failed/bulging caps.
the other ones won't be far behind..

[MonSync]

Re: Flickering monitor - Samsung 226BW

Hi - just signed up to say that I too had a flickering SyncMaster 226bw monitor and thanks to the help on this thread (and a friend with a handy soldering iron), the caps have been replaced and it's now working perfectly - thanks very much guys.

I ordered my capacitors from RS who supply in packs of 5, so I now have some spare. If anyone is in the UK and looking to fix the same monitor, drop me a message and I'll post them over.

Geoff