I found an open 270Ohm resistor on the board and
I've found some caps I
 don't trust.  The resistor was between a diode and "C4 NEG" 
Which type of power supply do you have?
  I just hope it's not transformer trouble!
 -24V and -12V are present so I doubt it's the transformer. 
 
So do I, but an open-circuit secondary winding could casue the lsos of
+24V only I think
-tony