[1000mp] Display Problem

[Arthur Delibert]

So after 4 years owning a Mark V, I got my "baptism" this weekend, when the display went dark.  The VA3CR website was a huge help -- it led me right to the problem and how to fix it.  (Blown fuse on the inverter board, behind the front panel.)

But here's the question:  Why are these fuses blowing in a radio that otherwise seems to be working fine?  Is there some other problem lurking in the display, or was the specified fuse just too small?  

After restoring the display, I let it run for half an hour with the front panel off, just to make sure nothing was obviously overheating.  (Watch out for high voltage on the inverter board.)  Seems fine.  

Any ideas on the root cause?

Thanks.

Art Delibert
KB3FJO