Many things

[Tony Duell]

> >Should it ever come to that -- that is that I can't get the parts to
> >_repair_ the hard drives (note : I would certainly consider making a
> >'clean box' to work on the inside of the HDA if necessary), then I would
> >grab the soldering iron, raid the junk box, and design an interface to a
> >more modern storage device. Heck, I've seen flash memory cards with more
> >storage than the hard drives in most of my machines....
> 
> Unfortunately this isn't an option for a lot of us.  I can pull off 
> some board level maintenance, but designing new parts is beyond me. 
> Thankfully my main PDP-11's and most of my VAXen have SCSI interfaces.

Please don't take this as a flame, but I am always suprised by the people 
who run classic computers (as opposed to running emulators) and who don't 
want to get into the hardware. To me [1] that's one of the reasons for 
running an old machine.

[1] And to a university computer society that I was a member of, which 
had a 'Hardware and Old Systems SIG'

Finding good spare parts gets significantly easier as the parts get 
smaller :-). Finding a complete board may well be next to impossibe, 
finding a TTL chip is relatively easy. Even if it's a custom chip that's 
failed, you might well be able to find a defective board with that chip 
still good on it. That's how my HP45 came into being, a friend gave me 
the contents of his junk box, including 2 dead HP45 logic boards, several 
dead and part-raided keyboard PCBs, etc. There were enough displays to 
completely populate a keyboard PCB (even if one of them has smaller 
digits than the other 2), of the logic boards, one had a dead A&R chip, 
the other had a dead C&T. I now have a pieced-together, working, 45.

The other thing is that even if you can't do the design, you may be able 
to copy xomebody else's (And you can be assured that anything I do 
related to classic computers will be shared). [Cue for the well-known 
story about the mathematician Littleword 'How ever little French I know, 
I am capable of copying a French sentence']

-tony