> > I was quite seriously considering such a technique in my
> next project.
> > Can I assume that you do not think this is wise?

I followed a project where a guy try out the ap note that has one connecting
the AC to inputs with series resistors, without, and in every manner
imaginable. It was rather sad to find that he had gone through an insane
number of PIC's before giving up. He had a particularly noisy AC line.

I suppose the idea would work if you could count on a clean AC line.
Transients on even a 120V line (such as a cheap lamp dimmer, noisy motor
nearby, etc..) will kill the PIC in a heart beat. Even the projects reported
on in this thread that worked were probably not analzed with a multi-channel
anlyzer or DSO with one analog channel tracking the Ac simultaneously. I
have seen very brief hits that show up on the PIC's RST pin that coincide
directly with captured line transients. Interestingly, the operation of the
PIC seems to continue with only minor hitches (a single bit may flip or a
register value may get garbled) and if the system includes a control loop
that will recover the hiccup may not ever be noticed. If I hadn't seen this
with my own eyes, I wouldn't report it here.

So I guess people would say that this method has worked for them, but it
always scoped as I described  - too sloppy for me. These are the products
that you can get signed off, but then have hi failure rates in the field.
No thanks....not for me.

Chris

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