I have two old solid state amps from the 80's, a Fender M80 combo, and a Peavey Stereo Chorus 212. 
On both, the speakers and cabinets work great, I made the 212 into a cab for a separate head, and have the amp sitting on a shelf.  Both amps have scratchy sounding pots and inputs, the power module on the Peavey is dead, and the Fender has a broken instrument input.  I'm looking for the opinions of those with some experience, is it worth the time and money to try and repair these amps, with the intention of keeping and maintaining them, or should I salvage them for what I can?  Also, are there people who take up these old amps as a challenge (donated), and then the parts wouldn't just end up in the dump?

Thanks!