Samsung 223BW power supply problem

[pawzilla]

Hy! I bought a 223BW monitor, used, and borken When I dissasembled it, I found out that somebody replaced the original capps with some Rubycon non standard value capps. There is no output voltage from the inverter, and the output voltage to the other pcb is 14.5V instead of the nominal 13.5V (with no 5V output on "B-dim" pin on the CN2 connector)

The monitor, when plugged in, turnes the blue power key on, but it can't be turned on, or exactly, there is no display picture.

One other thing I think, that is worth mentioning is a squeaking noise from the transformator.

My question is, can ti be, that the inverter doesnt work because of the wrong capps, or the 5V output?

I'm new in this sort of electronics, and my english is really bad, as you can see, but I will apriciate any help with this psu problem


Shot at 2012-02-23


Shot at 2012-02-23


Shot at 2012-02-23

[selldoor]

Re: Samsung 223BW power supply problem

Hi - Welcome - Your thread is probably being passed over as you have broken/bent a number of the rules put in place to make life a bit easier. I have decided to reply as it is probably due to your English - some fluent english speakers have problems anyway.

Not in any particular order: when joining you have not completed the country you live in nor the mains voltage. The reasons for these questions are that not everyone looks at the New Member post. I see that you are from Croatia so can immediately make allowances for the English, which is actually very good. It is useful in suggesting where to buy parts and also as in your case there are some other members from the same country who may suggest things based on local knowledge.

The Voltage- most members are in the US/Canada so they think at 120v. If they advise you to do something thinking 120v it could be a big bang not to mention dangerous for you.

Next thing is the photos. Whilst not too bad we do ask that they are not posted in line. Recommended size is no bigger than 2000x 2000 jpg file no bigger than 2mb.
They are posted using "Go Advanced" under post quick reply and then "Manage attachments"
There is also flash or glare which makes parts of the board difficult to read - I could not see the board number /revision. The view of the bottom needs re taken as when enlarged it is not easy to see in the detail required.
Lecture over:

I found out that somebody replaced the original capps with some Rubycon non standard value capps.


In what way are the caps Non Standard? How did you know?


There is no output voltage from the inverter,

This is not usually measured as it 1000 -2000volts+
How did you measure.

and the output voltage to the other pcb is 14.5V instead of the nominal 13.5V

Probably acceptable with no load.

(with no 5V output on "B-dim" pin on the CN2 connector)

Which is CN2 and are the voltages shown on the board?
A picture of that would be useful



The monitor, when plugged in, turnes the blue power key on, but it can't be turned on, or exactly, there is no display picture.

Does the blue power light stay on?

Do the "back lights" - ccfls flash on at all, at any time?

With it all connected up and using a computer showing a vivid desktop can you see an image on the screen by shining a torch or bright light on it.


One other thing I think, that is worth mentioning is a squeaking noise from the transformator.

My question is, can ti be, that the inverter doesnt work because of the wrong capps, or the 5V output?

Yes & Yes