[Coco] Remove C66 and c65 or just snip one leg?

[Gene Heskett]

On Monday 08 July 2019 14:37:58 Ed Snider wrote:

> Along with R22 and R23, they create a small RC delay on the /CAS and
> /RAS lines which probably improves DRAM reliability in the standard
> configuration.  That wouldn't be needed for the SRAM based upgrades.
>
> - Ed

I've allways been under the impresion they were there to reduce the 
digital noise footprint per FCC regulations.

> > On Jul 8, 2019, at 11:17 AM, rietveld rietveld
> > <rietveldh at hotmail.com> wrote:
> >
> > What is the reason they are needed for a 128k coco but not a 512k or
> > bigger coco?

The increased loading of the bigger memory chips may have slowed the slew 
rates of the signals enough the caps weren't needed, and or they weren't 
subjected to the same tests the complete coco had to pass.
> >
> > Sent from my BlackBerry 10 smartphone.
> >  Original Message
> > From: Ed Snider
> > Sent: Monday, July 8, 2019 12:10 PM
> > To: CoCoList for Color Computer Enthusiasts
> > Reply To: CoCoList for Color Computer Enthusiasts
> > Subject: Re: [Coco] Remove C66 and c65 or just snip one leg?
> >
> >
> > Not really, but there's no reason to not simply remove them
> > completely, unless you really want to be able to go back to the
> > original configuration (in a messy fashion).
> >
> > I'd just clip them out completely.  Seems a bit neater than having
> > some one-legged caps hanging out in there.  :)
> >
> > - Ed
> >
> >> On Jul 8, 2019, at 10:26 AM, rietveld rietveld
> >> <rietveldh at hotmail.com> wrote:
> >>
> >> I just picked up a vintage PBJ 512 memory upgrade. The instructions
> >> say to remove c65 and c66.   I have always just snipped one leg of
> >> each. Is there any difference in removing them?
> >>
> >>
> >> I cut 65 and removed 66.   Everything seems to work fine?
> >>
> >> Sent from my BlackBerry 10 smartphone.
> >>
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> >
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Cheers, Gene Heskett
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