SAMSUNG T240, "2 seconds to black" resistor "R301" size?

[Jan_T]

Hi there
I have the Samsung Syncmaster T240-problem "2 seconds to black" as many others.
BUT only when the display has been used for some time. Not from "cold start".

My inverter-transformer (printed name on curcuit board "T301") isn't blackening (due to heat) the curcuit board as others has seen on their board though.
Instead the resistor next to it, the one named "R301" is blackening the board.
When I measure the connections on the inverter "T301" between the connections on one of the 2 longsides of the "T301" I get ohm-readings, but not when measuring between connections on 1 longside to the other longside.
AND the resistor "R301" shows "open" (no connection) when measuring it.
So it is probably melted inside the "R301".
The color of the size-coloring rings on the resistor can not be determined with certainty because of a little burned look.
The colors looks like brown, white and white ending with the bronze-looking tolerance-code.
The physical size of the resistor indicates that it is a 2 or 3 watts resistor.
The picture that badcaps-member r00x has posted on 09-03-2011, 11:52 pm shows a physically smaller resistor R301 than the 1 on my board and another color-code containing black or some other dark color. It may or may NOT be the same resistor size in ohms because the layout of the curcuit board is not the same. Mine is Rev.2.0 2009.02.20. (Information located right next to the end of the inverter transformer "T301")
I have ordered a new Inverter Transformer TM-10160 but will have to put in a new resistor too.
Could be the "R301" has a gap in its wiring small enough for a high voltage spark to initiate the current that has flow through it so that the display can start when cold? Just a theory....
Can anyone help with the size of the resistor "R301" ?? OR
does anyone know if the size in ohms corresponding to the color-coding brown,white,white (=199 ohms) seems reasonable?
Jan_T The Viking

[ben7]

Re: SAMSUNG T240, "2 seconds to black" resistor "R301" size?

Hi there
I have the Samsung Syncmaster T240-problem "2 seconds to black" as many others.
BUT only when the display has been used for some time. Not from "cold start".

My inverter-transformer (printed name on curcuit board "T301") isn't blackening (due to heat) the curcuit board as others has seen on their board though.
Instead the resistor next to it, the one named "R301" is blackening the board.
When I measure the connections on the inverter "T301" between the connections on one of the 2 longsides of the "T301" I get ohm-readings, but not when measuring between connections on 1 longside to the other longside.
AND the resistor "R301" shows "open" (no connection) when measuring it.
So it is probably melted inside the "R301".
The color of the size-coloring rings on the resistor can not be determined with certainty because of a little burned look.
The colors looks like brown, white and white ending with the bronze-looking tolerance-code.
The physical size of the resistor indicates that it is a 2 or 3 watts resistor.
The picture that badcaps-member r00x has posted on 09-03-2011, 11:52 pm shows a physically smaller resistor R301 than the 1 on my board and another color-code containing black or some other dark color. It may or may NOT be the same resistor size in ohms because the layout of the curcuit board is not the same. Mine is Rev.2.0 2009.02.20. (Information located right next to the end of the inverter transformer "T301")
I have ordered a new Inverter Transformer TM-10160 but will have to put in a new resistor too.
Could be the "R301" has a gap in its wiring small enough for a high voltage spark to initiate the current that has flow through it so that the display can start when cold? Just a theory....
Can anyone help with the size of the resistor "R301" ?? OR
does anyone know if the size in ohms corresponding to the color-coding brown,white,white (=199 ohms) seems reasonable?
Jan_T The Viking

If it looks like a 2 or 3 watt resistor, then go with a 3 watt resistor to be safe.

The color coding 'brown-white-white' will give you an insanely high resistance. A picture I found online shows the resistor I think you are looking for. (its R301, right above the inverter transformer, right? - that would be a 100k-ohm resistor ('brown-black-yellow-gold') It is a flame-proof resistor, so be SURE to get a replacement that is flame-proof also!)

[Jan_T]

Re: SAMSUNG T240, "2 seconds to black" resistor "R301" size?

Thank You for the reply ben7.
Yes its the one right above the inverter transformer.
It looks as if You are right. 100Kohm sounds more reasonable. Not much you can do with a 14000000Kohm resistor, unless you want to save power....

[selldoor]

Re: SAMSUNG T240, "2 seconds to black" resistor "R301" size?

I dont know how you could mistake Brown white white for Brown black yellow
How about putting up a picture of it.

[selldoor]

Re: SAMSUNG T240, "2 seconds to black" resistor "R301" size?

Also the transformer is not a standard 4 corner secondary one
See here:http://www.lcdparts.net/TransformerD...ProductID=3696

You have to measure S1 >S2 and S3>S4 along one side. - you may have wasted your money there.

[ben7]

Re: SAMSUNG T240, "2 seconds to black" resistor "R301" size?

I dont know how you could mistake Brown white white for Brown black yellow
How about putting up a picture of it.

^ He stated that it is very burned.

I think its strange for it to fail like that - I wonder if one of the blue capacitors is shorted.

[selldoor]

Re: SAMSUNG T240, "2 seconds to black" resistor "R301" size?

He said a little burned - I am just worried that he has a totally different board. I think we need to see a pic of both sides of the board to judge the extent and possible cause of the damage.