--- Arthur Brown <artb@CABLEINET.CO.UK> wrote:
> I recall a memory board that was wirewraped we this
> used on a 8080 sbc micro
> controller, The power supply was the problem the
> wire all went in the same
> direction across the board, we removed the power and
> rewired the power at
> 900 with a larger gauge wire from 35g to 22g {if my
> memory is ok... no pun
> here} This and loads of caps sorted the noise
> problem.

---- Where do I place the caps and what kind of caps
to use? I only have bypass capacitors in every digital
chip.

> also some people run all the wraps in a cableform
> the noise from other wire
> are unbelivable, I liked to wire point to point
> myself.
>
> ----- Original Message -----
> From: Chris Eddy <ceddy@NB.NET>
> To: <PICLIST@MITVMA.MIT.EDU>
> Sent: Wednesday, March 22, 2000 8:20 PM
> Subject: Re: (ot) noisy wire-wrapped project
>
>
> | Jane;
> |
> | I will put a case of beer on power supply routing
> on your prototype.
> |
> | All audio and digital grounds must be kept
> seperate.

----- Yes, I separated the analog and digital ground
and combine them only at the power supply connection.

Return them seperately to the central power point with
a big filter cap at the center.

----- What? Forgive me but I can't figure out what
you're saying. You mean I put a capacitor at between
the analog and digital ground? What kind of capacitor
is that? What's the orientation?

Never mix ana and digi together.
> | (the secret is not wire gauge, but the fact that
> digital switch currents
> | are passing through the same ground traces that
> you are using for your
> | analog circuits).
> |
> | Also, add the obligatory 0.1 mic caps everywhere.
----- I have 0.1 bypass capacitors in every digital
ICs and some of the analog ICs.

 But they will not make up for ground layout.
> |


> | Chris Eddy
> |
> | >
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