If the transistors are there, they are going to be using them but you might have bad one. Where is the 2a fuse, in the supply or the load? Do you have a scope? There may be a problem with the rectifier or filter that is putting AC or a bad ripple on the bulk DC to the regulator.
These things are really pretty simple devices. It looks like a center tapped transformer feeding 2 diodes, some filtering and the pass regulator.
I removed the transistors and tested each one. Using a DMM set to ohms, positive lead to collector, negative lead to emitter which gave me O/L. Then I connected the base to the collector and it showed a high resistance reading.
Right now I'm testing all the caps...
The 2A fuse is on the secondary of the transformer and yes, I have an older analog scope.
