1 Dec
2005
1 Dec
'05
3:04 p.m.
Hi
I looked at the schematic and the parts you'd indicated.
It looks like one of them was one off and was R55 and not
D11. From the looks, it might be that you have other failures
in the supply. You've indicated R11, R21 and R55. These
are all part of the circuit that drives the primary switcher
transistor through T3.
Having looked at the printset, the first thing that struck me is that
these are all high power resistors (2 or 3 watt rating). They would
naturally run hot, therefore, and may look discoloured without there
being anything wrong with them.
Before we dive into this PSU, I would be interested to know if the thing
produces any output voltage, and if those 3 resistors test bad on an
ohmmeter.
-tony