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Mungo \Two Sheds\ Toadfoot Mungo \Two Sheds\ Toadfoot is offline
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Default FAO Clint Sharp...

Andrew Gabriel wrote:
In article ,
"Mungo \"Two Sheds\" Toadfoot" writes:
...and others wot know about Roland keyboards/power supply boards
again.

Here's some piccies... http://photobucket.com/gytha_ogg

Anything there identifiable as a potential reset-causer?


In picture 2, at the back, there's a component lead just
visible with some charring of the circuit board. In
picture 3, it looks like a 180ohm resistor, but the leads
and board aren't visible. That could be a thermal/dry joint
candidate.

Need to see the underside of the board for any charring
and quality of the soldering.


It must be very difficult diagnosing faults from photos

No, there's no charring on the board at all, despite appearances from my
not-good photos. I've re-soldered everything which looks even slightly
suspect underneath, even though there was nothing at all which made me think
"That's the problem". I sucked all the old solder off the joints and re-made
them at the correct temperature, i.e. the new solder flowed properly.

Thing is, I've seen dodgy joints, burnt boards and damaged components in the
past so I do have an *idea* of what to look out for, but I've no clue how
circuit boards work so I'm unable to look at a component and know that it
could cause the problem. They're Italian boards too. Great.

I'll take some underside pics soon, just in case I've missed something.

Si