Hi Roger,

Pin input should generally not exceed Vcc on most ICs including the PIC. Your A/D input should be lowered by some means to 5V maximum (assuming you are supplying 5V to the PIC). Probably the simplest way to do this is with a voltage divider.
See Darrel’s helpful post:
http://www.picbasic.co.uk/forum/show...=2010#post2010

There are ways to negate the regulator’s 1.2V. All ways would add to your circuit complexity. Depends if you want to just subtract it from the PIC A/D reading, or really make the output from the regulator go all the way down to zero volts. You may want to bump the resolution up from 8 bits to 10 bits and just work around the missing 1.2V chunk with programming.
Anyway, don’t put more that the supply voltage into the pins (or negative voltage either ).

-Adam-