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Thread: Value of this Resistor

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    Default Value of this Resistor

    Hi all,

    Having a go at repairing a Samsung Monitor 24".
    I'm guessing the burnt out bits was the resistor arcing away merrily as both connections at the pads were even loose! Yet is still fired up, gave a screen for about 2 seconds....

    As a first step I'm going to replace the resistor and re-track the tracks and then see how it goes.

    I can't work out the two middle bands, they look white or yellow, plus I would have assumed that they would be the same as they are used for the backlighting.

    Any clues as the value of this Resistor, and is it 1Watt?

    Cheers,
    GT250.




Look Here ->
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    calculator

    Last edited by diavalo13666; 16-05-17 at 05:14 PM.
    Never take your partner or loved one for granted life is so short

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    Rule one, get circuit or trace tracks to find WHY. res burnt. Will be sumping drawing TOO mucho current.. Otherwise you are wasting your time thinking r/p res will Fix prob!.

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    As Tom Mix says, without the schematic, you are only guessing. When resistors get hot like that, the colour code bands often change colour, and can't be relied upon to work out resistance.

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    First thing to do is remove it from circuit and measure its current value to see if works for the readable colour bands.
    If it is only a case of hot joint, the resistor may be still close to value.

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    Check and see if the manual is at the link below. Plus what is the model number ?


    Last edited by mickstv; 16-05-17 at 10:35 PM.

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    Monitor is a B2430L

    I'll pull the res out later tonight and check its value.

    I only decided to 'have a go', as it powered up ok. Screen lit up for a few seconds showing the Windows Desktop, and I thought it would be a easy cap job on the P/S...!!

    Just thought I'd post the Res as I wasn't going to be confident as to its value in case the colour bands had changed.

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    If you can't find a schematic for your monitor, have a look on the back of the board and find the part number of the board. It will be something like CN08BN44-00323A?????? . then do google image search on that number, and you will most likely pic up some images on ebay. You can then zoom in on the parts to see if you can find a similar colour code match. There seems to be a bit of variation on that board for different models etc, so make sure that the one you follow is the same.

    As for the resistor, it will likely be high in value, due to the amount of heat it has suffered. Also, with the replacement, it looks like it is a low flammability type.

    similar board here:
    But note values look different to yours.





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    Also as with all electronic boards, when one part cooks it usually weakens/stresses/destroys adjacent parts as well!

    And as tom mix said SOMETHING caused it too cook . . . it just didn't take the day off on it's own!

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    Can you take a photo of the other side of the board ?
    I'd like to see what it looks like behind those resistors.

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    I measured the R and it's reading 350K

    Bob - CN08BN4400323A SK285SCTE019 Rev 1.0
    Your ebay link shows (what appears to be the correct PCB replacement), - It's a Rev 1.2! and the R's are the same value, whereas mine are certainly not the same, unless the heat has seriously 'mis-coloured' them.


    Loopy - I'll take photo later this afternoon. Didn't get back till late late last night

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    A set of schematics might show what R923 value is ??

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    Quote Originally Posted by cmangle View Post
    A set of schematics might show what R923 value is ??
    It'd be pretty useless if it didn't LOL.
    The problem is, finding a set of schematics.

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    There are many internet sites where the manual is available for a fee, including .

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    Here's the other side Loopy. Pretty burn't up there...


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    Well, I've cleaned up the board and will have a go at putting the R back in and I'll use some thick cable links to the relevant pad connections.

    I'll do it tomorrow when I have some time

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    Hi GT, have you cut out all the burn't area between the tracks if not drill it out then get a round file to clean it up. Otherwise the carbon will track due to the high voltages.

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    Quote Originally Posted by mickstv View Post
    Hi GT, have you cut out all the burn't area between the tracks if not drill it out then get a round file to clean it up. Otherwise the carbon will track due to the high voltages.
    Yep...That's a pretty seriously burnt PCB.
    You might have room to drill a few holes and mount the new resistors in the open area just above where they are now, then join up with some wires, but I wouldn't go too far away from the transformer.
    Sorry I can't help with a diagram.

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    IT WORKS!!!

    Well, sort of

    Yeah Mictstv, I did clear the carbon away and cleaned what I could. Got some thick cable and soldered it all up and put it all back together again.

    First of all it didn't fire up when the PC was turned on, but as it's a touch on/off I'm not familiar with screens without a physical on/on button - so I assume that it's always 'on' from default.
    It then required two presses of the on/off button to power up and the screen was fine. Didn't power down, didn't power off - but! Each time that I did power down the PC and back on, dual power press, there was a fairly loud 'click' inside the screen.
    No smell. No sound of arcing. Left the misses with it for an hour or two and no smells no sound nothing.

    Powered down. Waited a couple of minutes. Back on (no auto turn on - and the two press power on), and that loud click...

    I'm not happy with this loud 'click'. So looks like it's a bin job. Somethings not right and after all I don't want it going belly up in a spectacular way

    Many, many thanks to for all your help people.
    GT250

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