Samsung Syncmaster 225BW

[selldoor]

Re: Samsung Syncmaster 225BW

I have not been aware of many members looking at lifetime of caps.
if you want a longer life you could go for this
http://www.digikey.com/product-detai...5CT-ND/3072165

By going up a voltage step you can get an FR series cap which is longer life.

[S0und]

Re: Samsung Syncmaster 225BW

I dont know what is available in Hungary - try to stick to leading brands - panasonic

Luckily, Farnell ships to Hungary.

http://www.digikey.com/product-detai...613747?cur=USD
http://www.digikey.com/product-detai...613752?cur=USD
http://www.digikey.com/product-detai...266330?cur=USD

Someone mentioned in the topic that FM series is a good choice. But caps lifetime variates from :

330uF - 4000 Hrs @ 105°C
820uF - 5000 Hrs @ 105°C
47uF - 1000 Hrs @ 105°C

so what is the priority, go with a good series, or aim for higher hour/°C

[selldoor]

Re: Samsung Syncmaster 225BW

If it is placed where it getting hot Temp is critical.
Lifetime usually suggests a good cap.
I dont know what is available in Hungary - try to stick to leading brands - panasonic
rubycon- nichicon- There is lots or info on here re series or look at what brands
/series are sold on the forum owners site
https://www.badcaps.net/kits/ then look at full stock.

Care if buying on ebay - lots of fakes about.

EDIT

I see you have posted similar before - the list you gave panasonic FM and FC are good for the purpose

Just check the physical size is ok.

[S0und]

Re: Samsung Syncmaster 225BW

I got a quick question, it's kinda stupid/obvious tho.

How important is the Life Time @ Temperature when i choose a cap? Should i go for 10k hour one? My friend told me that it's not that important.

[jlk69]

Re: Samsung Syncmaster 225BW

No, test lamps lit for 10 min then shut off on one test only. After that lamps went out on all tests after a few seconds.

[selldoor]

Re: Samsung Syncmaster 225BW

OK so now you have a pair of bulbs that stay on -yes?
So on the other pair use just one test lamp and one bulb
and then one test lamp and the other bulb, to try and narrow it down further.

Can you tell on the panel where the bulbs that light are - top/ bottom
one side or whatever.

Until it is established whether the bulbs and transformers are good
there is no point doing other tests yet.

[jlk69]

Re: Samsung Syncmaster 225BW

That was with both test lamps on one side. Additional test show lamps turning off after a few seconds. According to the guide there are more tests to run but I don't know the location of the components.

[selldoor]

Re: Samsung Syncmaster 225BW

Is that 10 minutes with its own lamps lit or both/one of the test lamps. Have you narrowed it down to just one or two faulty ccfls. I think you should just run the test for a minute or two at a time.

[jlk69]

Re: Samsung Syncmaster 225BW

Well after several tests I got the lamps to stay on for a while after hooking it up to VGA port by itself. First couple of times lamps only stayed like a few seconds. Both test lamps and display are flickering badly. Several minutes have now passed with lamps still on. I can see dim image on screen. Lamps went out after maybe 10 minutes but can still see image on screen with bright light on.

[budm]

Re: Samsung Syncmaster 225BW

So the way you test it, you put two test lamps in two lamp sockets (other two sockets have the LCD's panel lamps attached) that are sitting next to each other then turn on the monitor with having hooking up to running PC, then it goes out after 10~15 seconds? Then you move the two test lamps to the other two sockets instead, and the LCD's panel lamps attached to the two sockets that had the test lamps attached, turn on the monitor with having the running PC, then it also goes out after 10~15 seconds.
Lamps turning off after 10~15 seconds sounds like the monitor goes into standby mode due to no video signal detected.

[jlk69]

Re: Samsung Syncmaster 225BW

OK, set up 2 small test lamps (the exact same 13 watt bulb). Did tests again. The lights always go out after 10-15 seconds max. Some time they only flicker. What does this mean? Seams to me that the CCFL lamps are good on my monitor. Is this a correct assumption? Please advise what the next test I should perform.

[budm]

Re: Samsung Syncmaster 225BW

That second big lamp is too big and it is trying to draw more current from the circuits, you need to make one more curly lamp.

[jlk69]

Re: Samsung Syncmaster 225BW

Made a second test lamp. The first few tests the lamps would stay on for a while but would flicker and a buzzing sound was coming from something but I could not figure out exactly which component. After trying several different combinations I only get a short flicker from bulbs when power is applied. Not sure where to go from here. Video of part of the test when stayed lit for a while.

[budm]

Re: Samsung Syncmaster 225BW

I would make one more test lamp since there is possibility of having two bad lamps.

[jlk69]

Re: Samsung Syncmaster 225BW

Just the figures would do - they seem to be within 3% so ok.
(never seen dots between each digit before.)
You need to examine the ends of the ccls for burning/bad wiring.
Do you have a spare bulb in another monitor or can you make one of these.
https://www.badcaps.net/forum/showthread.php?t=19987

OK, made a test lamp. I tried out on monitor with everything plugged in including the 3 other CCFL's. Lamp lit up for a few seconds then shut off. I tried this test with all 4 of the sockets and got similar results. I started with cn5 socket then did cn6 then cn4 and finally cn3. Each time the lamp stayed lit for a shorter amount of time. Did I do the test correctly? Should I make up another test lamp?

[selldoor]

Re: Samsung Syncmaster 225BW

I only have 1 other LCD monitor but it is the one i am using right now a Viewsonic VA903b. Will try to set up something to test. I looked at where the ends of the ccls but have not disassembled any more. Is it easy to take out the ccls.

Not easy - they get very brittle but initial test is just by plugging something into the socket on the powersupply to see if one bulb or the wiring is causing a problem.

As it is difficult to tell from the quick flash what bulbs are lit, another thing you could try is you disconnect all but one ccfl lead and see if it flashes then unplug lead 1 and plug in lead two and see if that flashes and so on.

CARE - High Voltage 1200v - machine should be off when plugging /unplugging

[jlk69]

Re: Samsung Syncmaster 225BW

I only have 1 other LCD monitor but it is the one i am using right now a Viewsonic VA903b. Will try to set up something to test. I looked at where the ends of the ccls but have not disassembled any more. Is it easy to take out the ccls.

[selldoor]

Re: Samsung Syncmaster 225BW

@selldoor re the decimal point

http://www.eevblog.com/forum/chat/re...900/#msg172900

http://www.eevblog.com/forum/chat/re...909/#msg172909

http://www.eevblog.com/forum/chat/re...979/#msg172979

Thanks
Hmm that could be interesting then. - perhaps OP should start on fixing his meter?

[retiredcaps]

Re: Samsung Syncmaster 225BW

(never seen dots between each digit before.)

@selldoor re the decimal point

http://www.eevblog.com/forum/chat/re...900/#msg172900

http://www.eevblog.com/forum/chat/re...909/#msg172909

http://www.eevblog.com/forum/chat/re...979/#msg172979

[selldoor]

Re: Samsung Syncmaster 225BW

Just the figures would do - they seem to be within 3% so ok.
(never seen dots between each digit before.)
You need to examine the ends of the ccls for burning/bad wiring.
Do you have a spare bulb in another monitor or can you make one of these.
https://www.badcaps.net/forum/showthread.php?t=19987