[BC] DAX and field repairable

[mrfixit@min.midco.net]

> Welcome to the 21st century. Since the DAX does the PDM encoding and
> distortion reduction in software, there isn't a lot to repair in the field.
> The chips are large arrays with far too many chips for you to slap your
> soldering iron on. Board level swappage is about all you can do, not
> component level t'shooting 

Ah, but you ARE doing component troubleshooting and repair. It's just that
the components are different. They still have "battery and ground", have
goenintas and goesouttas, and are about as easy now to change as tubes 
are/were (pull one out, put one in, see if that fixes the problem(s).

This philosophy drove me nuts years ago when the first generation of 
our stuff started going that way. Until it occured to me that now instead
of unsoldering something that had a proper input and improper
output and then putting a new one in, I now just pull a card that (probably)
had a good input(s) and bad output(s). 

It's the uncertainty of that "probably" that is still disconcerting to me.

Dave Dunsmoor