[This followup was posted to sci.electronics.repair and a copy was sent
to the cited author.]

In article ,
says...

On Sun, 26 May 2013 13:08:53 -0700, Michael Karas
wrote:

[This followup was posted to sci.electronics.repair and a copy was sent
to the cited author.]

In article ,
says...

Excellent pictures, thanks. I believe the actual marking code is DF;
the R indicates the gain and the G is a prouction lot or date code.

My favorite source for arcane marking info: http://www.s-manuals.com

Which leads to: http://www.s-manuals.com/smd/df

And the datasheet: (watych out for line breaks)
http://www.s-manuals.com/pdf/datashe...C_2sd1768s%2C_
2sd1863%2C_2sd1898_rohm.pdf
IF you are in the USA, they are available from Digi-Key
(ww.digikey.com) for $.53 each. (Choose USPS First Class Mail for
lowest shipping cost.)

As a general rule, I dissaprove of replacing parts because they 'look
bad'. A few minutes making measurements with a DVM can give a wealth
of information.

PlainBill

THanks for the info. I had also done some research on some other sites
and find that there are multiple possibilities for this device marked
with a DF.

Sanyo NPN 2SD1623
Philips PNP BF621
Siemens PNP BNF21
Rohm NPN 2SD1898 **

** The part that you located.

Note that the marking codes seem to be chosen by the manufacturer.
Always make sure you are dealing with the same package type.

PlainBill

Well, I received the new capacitors for the monitor power supply and got
those installed. The power supply fired right up and produced its 5V
STBY output. I then tested the other outputs by connecting the PSON
signal on one of the connectors over to the 5V STBY and all of the +5, +
12 and +24 volt rails all came up. I tested the thing on the bench with
some load on each output and it works nicely.

Unfortunately when the PSU is mated up with the video controller board
in the monitor it fails to come up and act like a monitor. The only
thing that does appear to work is that the EDID device does provide
valid data back out through the D-Sub HD15 connector to a host computer.
It shows the proper native monitor ID strings and the correct native
resolution. But no other functioning is in operation.

Since this thing was given to me for free and the fact that it only
supports analog VGA signalling (no DVI connector) I will probably not
spend any more time futzing around with it.

--

Michael Karas
Carousel Design Solutions
http://www.carousel-design.com