> >> Sprinkle liberally.
> >
> >What value cap would you use?

I don't know if people have pointed out that IT IS CLAIMED THAT the
capacitors used in modern equipment should be substantially SMALLER
electrically than they used to be. This may sound ridiculous (and maybe it
is) but ...

The argument goes like this: Bypass capacitors join ground to supply with as
short as possible a signal path for electrical noise. The capacitor also has
lead inductance and the overall combination has both series resonant and
antiresonant frequencies. Near resonance the capacitor is a far better
decoupling element than at other frequencies. As system frequencies rise the
capacitor value required to place capacitor resonance near the main noise
frequencies of interest drops.

In the "good old days" with clock speeds in the sub 1 MHz to say 10 Mhz
range a 0.1 uF (100 NF) capacitor was often used. With clock frequencies in
the 10 to 100 MHz range much smaller capacitor values may be appropriate -
say 0.01 uF or even less.

Note that it can be useful to parallel several capacitors of widely
different values at the one location. This has been standard RF practice for
many decades. Note that paralleling can lead to unexpected results.


Read this interesting paper to get scared

         http://www.ultracad.com/esrbcap.pdf

    Related        http://www.ultracad.com/esr.htm


                                     ************ HOWEVER **************

Here are the views of Ivor Catt, a very experienced heretic who claims that
the whole idea is bunkum.
He specifically derides the above paper and many others.

        http://www.ivorcatt.com/2603.htm

Also see the many references gives (and criticises).

Ivor's main point is that there is no known mechanism for creation of
inductance within most capacitors and that lead length is the overwhelming
contributing factor. He backs up this assertion with some interesting data.



        RM

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