Omer Yalhi wrote :

> 1. If I touch (with my bare finger) to the cap that is
> connected to the RB7
> pin of the pic (where the xtal's one pin is connected) the
> unit does not wake up

These "clock-crystals" are made to run in a very low-energy,
low-power environment. That also makes them sensitive. To
intruduce the (rellativily) large capacitance
in your finger/hand, probably upsets the crystal a lot.

> The cap is 22pF.

And your fingers may add several 100's of pF's to that.

>
> Why does this happen?  Bad board design?

Don't have to be. Just keep your hands in your pockets :-)

Note also that most PIC data sheets has some examples of
board design (often together with the timer1 desription)
that might help in making the tmr1 osc more stable.

Regards
Jan-Erik.

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