[Amps] Heath SB1000 blowing fuses, fault finding suggestions.

[Mike & Becca Krzystyniak]

   I'm working on a SB1000 from an estate that sat idle for maybe a decade,
and prior to that it had little use.  Last known it was working but now it
is blowing fuses...

   I have pulled both HV secondary wires off the rectifier board and also
pulled the wires from LV secondary.  To be safe I also removed the tube but
the amp still blows the fuses. 

   As I am working back to the AC plug it's starting to look like the power
transformer is shorted in some manner.  But I have never seen one go bad
before from "sitting idle".  The only other element to isolate is the
AC-main on-off relay.  So I'm thinking that the problem is either a fault in
the AC Mains relay when it engages or some fault in the power XFMR. 

   Has anyone here chased a similar problem before?  Is there a simple way
to confirm one or the other?

   Thanks in advance for your thoughts and comments.

73's  Mike K9MK