Citation 22 suddenly blowing fuses, anyone help?

My dad's old Citation has been working perfectly for going on 20 years, I guess, and just the other day it started going into protect every so often. As of yesterday, it's not powering up, so I pulled the case to reveal one of it's two 5A fuses was blown. Replaced the fuse, and it blew again as soon as I powered on. I've read that these amps were sometimes incorrectly biased from the factory, which might explain the largish amount of heat generated lately. Has anyone had a similar experience w/ a Cit 22/24? Fixable? Thanks very much for any thoughts, Bill Pitz
Caps, The Capacitors in any electronic product dry up eventually. 20 years is a long time for caps. Good thing it blows the fuse. If you replace the powersupply caps, it may work for a good while longer. Replace all the big caps, and you may have another 20 years!
This IS after all, a guess, but a good guess.
(The bad caps may have damaged some other components, but usually not)
I have a Cit 24 - almost the same amp. These were made into the mid/late 80s and if it's had regular use, it's not the caps. (these don't have a lot of 'big caps' in general, not like a vintage tube amp built with electrolytics ala CJ et al. ) Mine works fine, but I'd look for something that spontaneously failed (resistor?), likely shorting an output or something which draws current enough to trip the mains fuse. Need a tech to look at it really, there's a lot of circuitry in there and barring obvious burned area or something, it's not a piece that is easy to troubleshoot w/o real test gear.

Good luck, it's worth getting it fixed. If not, email me - I'd be interested in it.

Thanks very much for the responses, folks. I think I'll have the caps checked, it seems in retrospect to have been a somewhat gradual failure, rather than a spontaneous one. Probably omitting the word 'suddenly' in the thread name would have been a good idea. Any other thoughts before I trundle this thing to the shop? Thanks again, Bill