OK... here are the bones of it:

1) You will need a LM317T chip (the type in a TO220 package).
Fortunately these are cheap and easily available.

2) You will also need a small clip-on heat sink for the LM317T.

3) When you have the above, unsolder Q3 from the circuit board and
remove.

4) The LM317T will need to be soldered onto the circuit board. The
attach points are: the end of the component marked 'LF125' nearest to
D14 for the input pin; the end of D14 nearest the power socket for the
output pin; the end of D14 furthest from the power socket for the
adjust pin. 

5) Now the fiddly bit: before soldering the LM317T is soldered in
place, you will need to cut and bend the three pins so that when
attached to the three points above, the chip and its heatsink lay
parallel to the circuit board without touching any of the components
underneath.

6) Solder the LM317T in place and check that the case can be
reassembled without pushing the body of the LM317T onto the circuit
board.

7) Test that everything is now working.

8) It is important to note that the LM317T is a linear regulator, so it
will generate more heat than the original swith mode circuit.For that
reason, it would be *very* advisabe to swich the SB3 off at the mains
when not in use rather then leaving it powered on 24x7.

I would describe the above as a bodge rather than a repair, but it
saved one of my SB3s from the bin. Note that if you try the above, it
is at your own risk.

It may be worth askng in the DIY section of this board if anyone there
can think of a more elegant solution than the above.


-- 
Adam_F
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View this thread: http://forums.slimdevices.com/showthread.php?t=80209

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