[Amps] Problem with Alpha 89 bought in 1994.

[W4ABW at aol.com]

As I sit here now with my FT-1000MP and Alpha 89 all is FB.
 
But for sure it won't last. The Alpha will go into a fault that will  
require the 3 minute timer to have to recycle or the amp will just shut down as  
if it was turned off. The fuses are good. Sometimes it will power up and 
then  shut down again almost immediately. Could I have a tube problem ? Any 
help much  appreciated. Its been this way for a year or so. Most times I can 
still use it  as it will finally behave.
 
I hope this is an appropriate list to send this question to.
 
73
Al Watson
W4ABW
Raleigh, NC