Re: Samsung Syncmaster 245BW



Hi again,
I just replaced the piece as you described also with a 22nF cap and it helped . Thanks for the hint, you made my day. I already bought the caps like 2 months ago because they came like 40 cents a piece just to make sure, but somehow I never suspected them to be the reason. So thanks again.

Best regards from Germany
bermudahonk...

Re: Samsung Syncmaster 245BW



Hi,
did your board also did not have 24V? and showed the same voltage readings on F9222L as it is in my case? I have Caps with 22n 630V. I'll give it a try next weekend. Thanks for the hint....

Re: Samsung Syncmaster 245B

Hi,
I'm also stuck with a broken 245b, no 24V but everything else working. I've cheked the RB805/7 resistors but they are OK. I check every part and used a working board to see a difference and still have no clue what's going on. I also got a new oscillator F9222L but with the same result. Somehow the curcuit is not oscillating, therefore I don't get 24V. Any Ideas?

Re: Samsung Syncmaster 245BW

Hi,
I got the new F9222L but still didn't get the unit to work. I also got another monitor that had a burned resistor RB805. This unit is working again. Now I have a working unit so I can check for differences and already done some stuff, but had no luck to find something. I figured out that voltage on pin 11 also is a feedback loop from 24V side. Because the faulty unit does not have 24V the voltage differs on that pin.
I'm still stuck. It seems, that somehow the unit isn't oscilating. I got high voltage ratings on primary winding. But...

Re: Samsung Syncmaster 245BW



It does not. The monitor stays on and shows the "no cable connected" screen. The idea with the white screen is to see if the lamps are on, while the monitor is laying face down. That way when you lift it a little bit, you'll see the reflections much easier....

Re: Samsung Syncmaster 245BW


Yes, just disconnect the plug between panel and the logic card....

Re: Samsung Syncmaster 245BW

Hi,
I checked everything ... well besides the SMD-caps but everything seems to be OK on that board of mine. The only thing that remains ist the F9222L. I will order one today. But since I will have to wait a few days until it's arrival, I'm still up for testing .

Re: Samsung Syncmaster 245BW

Hi,
I was checking the path to pin 11, since I get there 4,62V and others get around 1V. I was using the schematics from zeha and my readings on QM803 didn't make any sense. So I cleand the surface of that item and could clearly read "3Ls". There was a fourth sign, but I could not recognize it. Still I looked the part up and as I guessed it should be some sort of an pnp thingy. I found out its a pnp double transistor. I drew it on paper and guessed my readings before making them. They turned out to be exact. I found the [URL="http://www.datasheetcatalog.org/datasheet/infineon/1-bcv62_1.pdf"]datasheet[/URL]....

Re: Samsung Syncmaster 245BW

Hello,
since no one has answered yet, I did the tests. In my case, I don't have 24V.


Yes they do. Standby is (as the name indicates) always at 5,2V. PSON shows 0V when the power button is off and about 3,6V when ist on (blue light).

Althought there are no marks on that picture i just followed your instuctions. When the power button is off there ist just around 30V sitting on the bottom pin. When power button is on (blue light) there is also 30V on the upper one.
In a few hours from now I will provide...

Re: Samsung Syncmaster 245BW

Hi,
I provided some better photos. In my case I measured the QM802 and althought it should be a npn transistor from my readings I would guess it's a pnp transistor. So I think I should replace it.
I'm from germany . I would be glad for some pointers on where to get the replacement. So far I just found shops which only sell huge amounts....

Re: Samsung Syncmaster 245BW

Hello guys,
I also posess a 245b without 24V. After looking around an taking measurements I only found that the resistor RB813 has no rings and is completly black. From a scematic attached by Zeha it should have a value of 1.5 Ohms. Can someone confirm this? You can find the resistor nearby TB810S. The resistor is not smelling burned, but it's odd to me that the body i just black. I'm reading 1.2 Ohms
Thanks in advance.
My readings on the F9222L (no 24V, blue light on):

Pin 04: 0V
Pin 07: 19,2V
Pin 10:...