\302 may be the octal code for A^ (A with a cap over it). The number is too high for it to be a decimal representation of an ASCII character. But that's just one possibility; it may also be Unicode. Perl (current versions) has Unicode support. U is seen literally. And ^K is "control K", which is a character that doesn't actually print visibly using more.

How can I convert that from raw to hex or raw to decimal?

You can use unpack, or use ord while iterating over each position in the string, to name a couple starting points.

How does it look to a regular expression?

It looks like a string of three characters: "A^" (I don't know the keystrokes for A with a cap over it), "U", and "^K" (control K). How you write your regexp will determine how the regexp deals with those characters.

Hope this helps...