25 Jun
2015
25 Jun
'15
6:37 a.m.
On Jun 25, 2015, at 7:16 AM, David Griffith <dave
at 661.org> wrote:
...
I don't think thatt making the flip-chips double-sided will be desirable. I want to
shrink the machine and minimize any need to reengineer the backplane. By the way, can the
backplane of a straight-eight be realized as a PCB?
Of course. The only reason a PCB backplane would be an issue is if there are signal
integrity concerns, but at DEC speeds that?s not going to be a problem. Especially if
what you?re aiming to replace is wire wrap which is in general worse at signal integrity
than PCB. Now if you were looking to replace the chassis wiring of a 6600 with a PCB,
that would be a different matter, then you?d want to be a bit more cautious. Even then
it?s clearly doable, if you use transmission line design on the PCB signals.
paul