gEDA-user: bypass caps

[Dave McGuire]

On Aug 21, 2006, at 12:19 PM, Stuart Brorson wrote:
> I believe that back in the 70s DEC used to use two layer boards with
> PWR and GND run on busses layed out on a rectilinear grid.  Signal
> traces were on top (IIRC) and PWR/GND on teh bottom.  The DIPs
> were layed out in rectangular rows following teh same grid.  Fingers
> would extend from the PWR and GND busses to each DIP to feed
> its power/ground pins.

   This is true of *some* DEC boards but definitely not all.  I see it 
on about 1/3 of them.  That scheme didn't seem to last long before they 
went to multilayer boards with embedded power/ground layers.  (I have 
~200 qbus, unibus, and omnibus boards here; I hack on 'em all the time)

             -Dave

--
Dave McGuire
Cape Coral, FL