Hi;

I'm trying to repair a Samsung Syncmaster flat panel monitor.
Model 240T (24")

There is video on the screen but dimly lit. The converter for the CCFL
took a good hit. There are several burned components in the DC
converter. Among the wreckage, are some smd transistors marked R03 and
R04.(marked right on the device) I have had no luck decoding this
label at all.

Some of the other R04 smd's check with a high reading like you'd
expect a FET would but I can't be sure.

Any help here would be appreciated. Especially if you have a print of
the converter on this unit
Thanks,
Spark

"Sparkey" wrote in message
ups.com...
Hi;

I'm trying to repair a Samsung Syncmaster flat panel monitor.
Model 240T (24")

There is video on the screen but dimly lit. The converter for the CCFL
took a good hit. There are several burned components in the DC
converter. Among the wreckage, are some smd transistors marked R03 and
R04.(marked right on the device) I have had no luck decoding this
label at all.

Some of the other R04 smd's check with a high reading like you'd
expect a FET would but I can't be sure.

Any help here would be appreciated. Especially if you have a print of
the converter on this unit
Thanks,
Spark

Sometimes, the inverter transistors fail as a result of other things such as
bad transformers. You might find it a cheaper and more reliable repair, to
just replace the inverter board complete. Most are available either as
originals or replacements.

Arfa

On Wed, 10 Oct 2007 09:14:48 -0700 Sparkey wrote in
Message id: . com:

Hi;

I'm trying to repair a Samsung Syncmaster flat panel monitor.
Model 240T (24")

There is video on the screen but dimly lit. The converter for the CCFL
took a good hit. There are several burned components in the DC
converter. Among the wreckage, are some smd transistors marked R03 and
R04.(marked right on the device) I have had no luck decoding this
label at all.

Some of the other R04 smd's check with a high reading like you'd
expect a FET would but I can't be sure.

Any help here would be appreciated. Especially if you have a print of
the converter on this unit

Converter? Do you mean to say inverter? If so, can you identify the
inverter's part number? Or, better yet, determine the part number of the
LCD panel?

Sparkey wrote:

I'm trying to repair a Samsung Syncmaster flat panel monitor.
Model 240T (24")

There is video on the screen but dimly lit. The converter for the CCFL
took a good hit. There are several burned components in the DC
converter. Among the wreckage, are some smd transistors marked R03 and
R04.(marked right on the device) I have had no luck decoding this
label at all.

The markings on SMD parts of this size are minimal and are usually in some
'code' which has to be interpreted.

Graham

On Oct 10, 12:14 pm, Sparkey wrote:
I'm trying to repair a Samsung Syncmaster flat panel monitor.
Model 240T (24")

There is video on the screen but dimly lit. The converter for the CCFL
took a good hit. There are several burned components in the DC
converter. Among the wreckage, are some smd transistors marked R03 and
R04.(marked right on the device) I have had no luck decoding this
label at all.

Some of the other R04 smd's check with a high reading like you'd
expect a FET would but I can't be sure.

I did a similar search recently for a code CF (still have to order it,
but
probably a Rohm 2SD2150). There are lists of marking codes online
(google 'SMD transistor marking code'), but most of them don't have
these transistors, which in at least one place were referred to as
Rohm type (though that may cover all Japanese manufacturers).

To do a brute force search, go to the B&D website and follow their
manufacturer links. Look for your package type in the selection
guides (SOT-89 is a common package for the inverter transistors,
but every manufacturer has a different name for it) and start
checking
datasheets. One or two manufacturers actually have tables with
marking codes, so you may luck out there. IIRC, only one or two
manufacturers used a one-letter, two-number pattern (don't remember
which), you might be able to readily narrow it down. Note that
these codes aren't unique, so you still need to do some reality
checking once you get a hit.

The other thing to search for is reference designs for the controller
IC used on the board (not immediately helpful in my case, but I did
learn that the circuit used is called a Royer oscillator, and some
subsequent searches yielded typical schematics and transistors
used). Presumably you've already googled the inverter model
number.

Good Luck!
TM

On Oct 11, 9:52 pm, wrote:
On Oct 10, 12:14 pm, Sparkey wrote:

I'm trying to repair a Samsung Syncmaster flat panel monitor.
Model 240T (24")

There is video on the screen but dimly lit. The converter for the CCFL
took a good hit. There are several burned components in the DC
converter. Among the wreckage, are some smd transistors marked R03 and
R04.(marked right on the device) I have had no luck decoding this
label at all.

Some of the other R04 smd's check with a high reading like you'd
expect a FET would but I can't be sure.

I did a similar search recently for a code CF (still have to order it,
but
probably a Rohm 2SD2150). There are lists of marking codes online
(google 'SMD transistor marking code'), but most of them don't have
these transistors, which in at least one place were referred to as
Rohm type (though that may cover all Japanese manufacturers).

To do a brute force search, go to the B&D website and follow their
manufacturer links. Look for your package type in the selection
guides (SOT-89 is a common package for the inverter transistors,
but every manufacturer has a different name for it) and start
checking
datasheets. One or two manufacturers actually have tables with
marking codes, so you may luck out there. IIRC, only one or two
manufacturers used a one-letter, two-number pattern (don't remember
which), you might be able to readily narrow it down. Note that
these codes aren't unique, so you still need to do some reality
checking once you get a hit.

The other thing to search for is reference designs for the controller
IC used on the board (not immediately helpful in my case, but I did
learn that the circuit used is called a Royer oscillator, and some
subsequent searches yielded typical schematics and transistors
used). Presumably you've already googled the inverter model
number.

Good Luck!
TM

"B&D website", does this mean Black and Decker website? could not find
any reference to Manufacturer links on Black and Deker website.

Regards,

Ravi.

On Oct 12, 12:23 am, wrote:
On Oct 11, 9:52 pm, wrote:



On Oct 10, 12:14 pm, Sparkey wrote:

I'm trying to repair a Samsung Syncmaster flat panel monitor.
Model 240T (24")

There is video on the screen but dimly lit. The converter for the CCFL
took a good hit. There are several burned components in the DC
converter. Among the wreckage, are some smd transistors marked R03 and
R04.(marked right on the device) I have had no luck decoding this
label at all.

Some of the other R04 smd's check with a high reading like you'd
expect a FET would but I can't be sure.

I did a similar search recently for a code CF (still have to order it,
but
probably a Rohm 2SD2150). There are lists of marking codes online
(google 'SMD transistor marking code'), but most of them don't have
these transistors, which in at least one place were referred to as
Rohm type (though that may cover all Japanese manufacturers).

To do a brute force search, go to the B&D website and follow their
manufacturer links. Look for your package type in the selection
guides (SOT-89 is a common package for the inverter transistors,
but every manufacturer has a different name for it) and start
checking
datasheets. One or two manufacturers actually have tables with
marking codes, so you may luck out there. IIRC, only one or two
manufacturers used a one-letter, two-number pattern (don't remember
which), you might be able to readily narrow it down. Note that
these codes aren't unique, so you still need to do some reality
checking once you get a hit.

The other thing to search for is reference designs for the controller
IC used on the board (not immediately helpful in my case, but I did
learn that the circuit used is called a Royer oscillator, and some
subsequent searches yielded typical schematics and transistors
used). Presumably you've already googled the inverter model
number.

Good Luck!
TM

"B&D website", does this mean Black and Decker website? could not find
any reference to Manufacturer links on Black and Deker website.

Regards,

Ravi.

Hi guys;

Yes, I did mean inverter board and I'm going to do the shotgun
search on B&D this afternoon to see if I can get any info from the
SOT-89 listing

I may end up ordering a new inverter, but I've got 3 of the 4 sections
of the thing working now. It's just the stubborn 4th section
thanks for the help, I will keep you posted on my progress.

spark

On Oct 12, 12:23 am, wrote:
On Oct 11, 9:52 pm, wrote:
To do a brute force search, go to the B&D website and follow their
manufacturer links.
"B&D website", does this mean Black and Decker website? could not find
any reference to Manufacturer links on Black and Deker website.

B&D Enterprises: http://www.bdent.com/

Unfortunately, they've changed around their website and no longer
have a direct link to a linecard. There's a link to specs, but you
need
to sign up first to access that page. Hopefully it's arranged so that
you can browse rather than just having a search engine (which is
all that's available on the transistors page).

TM

On Oct 12, 11:41 pm, wrote:
On Oct 12, 12:23 am, wrote:

On Oct 11, 9:52 pm, wrote:
To do a brute force search, go to the B&D website and follow their
manufacturer links.
"B&D website", does this mean Black and Decker website? could not find
any reference to Manufacturer links on Black and Deker website.

B&D Enterprises:http://www.bdent.com/

Unfortunately, they've changed around their website and no longer
have a direct link to a linecard. There's a link to specs, but you
need
to sign up first to access that page. Hopefully it's arranged so that
you can browse rather than just having a search engine (which is
all that's available on the transistors page).

TM

I checked. It's only a search engine. Getting any part information is
not easy on this website.

Regards,

Ravi

On Oct 13, 3:05 am, wrote:
On Oct 12, 11:41 pm, wrote:
On Oct 12, 12:23 am, wrote:
On Oct 11, 9:52 pm, wrote:
To do a brute force search, go to the B&D website and follow their
manufacturer links.
"B&D website", does this mean Black and Decker website? could not find
any reference to Manufacturer links on Black and Deker website.

B&D Enterprises:http://www.bdent.com/

Unfortunately, they've changed around their website and no longer
have a direct link to a linecard. There's a link to specs, but you
need to sign up first to access that page. Hopefully it's arranged
so that you can browse rather than just having a search engine
(which is all that's available on the transistors page).

I checked. It's only a search engine. Getting any part information is
not easy on this website.

The old B&D homepage is available at the Internet Archive
(http://www.archive.org/index.php)
e.g. http://web.archive.org/web/200707052...www.bdent.com/
At least some manufacturer pages are still available on the B&D site,
just not linked from the new homepage. The pages also appear to be
archived.

TM