question about zombie chorus

[makkimo]

hi!
i'm building one of this zombie(R.G.Keen) ...this is my simple q:
why c6 & c7 are listed to be from 100 to 470 uf, what's the difference between values
thanks

[Mark Hammer]

Those caps reduce power-supply related noise.  C6 smooths the overall power supply, and C7 "decouples" the Vref supply, which is another type of smoothing.  In these cases, there are no absolute values needed.  "More" is usually "better", but after a certain value there is nothing to be gained.  100uf is fine for C6 but 220uf can be better.  For C7, anything more than 100uf is "overkill".  You can probably even go with 47uf for C7.  If you look at many other schematics you will often see caps as low as 10uf or LESS doing the same thing.

[makkimo]

mmm very interesting
you are very kind

i'm looking now at the pcb and what about the traces that seem to be cutted (going to nowhere) are they necessary for some oscure reasons???

[Mark Hammer]

I believe they are there as what are called "ground planes".

There is another layout for the Zombie at Marcos/Munky's website that includes most of the mods that have been suggested by people here.  These will make your Zombie a more flexible and interesting pedal.  RG did a great job with the layout, and John Hollis provided an excellent design, but the version at Munky's site is better.

[ethrbunny]

There is another layout for the Zombie at Marcos/Munky's website

<ignorance>
and the URL would be?
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