[sdiy] sample and (infinite) hold

[Roy J. Tellason]

On Wednesday 05 January 2005 04:50 pm, Richard Wentk wrote:
> At 21:29 05/01/2005, Scott Juskiw wrote:
> >I'm using a polypropylene at the momen., I've tried polycarbonate,
> >polystyrene, they all droop eventually.

This sounds like the right sort of cap to me...

<...>

> You can do 20 minutes with analogue. You can't do 20 days, or the full
> length of a Klaus Schulze piece. :-)

:-)

> One thing to consider is circuit board leakage. Some designs put a guard
> track around the hold cap which helps keep the charge in.

This is the other area that I was thinking might be a part of the problem.  I 
remember some discussion on the subject when I went up to ARP,  and how they 
had to stop using coatings for the board (soldermask, etc.) because of 
problems in this regard.  It's also extremely important to clean things up 
after soldering,  not leave any flux residue,  etc.  Maybe some of that has a 
bearing on this?

Physical arrangement does seem to also be rather important.