Thanks Mags. The cable box is Scientific Atlanta Explorer 4250 HDC.
You're right the connection is optical video out. I was getting confused last nite.
In order to get surround do I connect the optical video out to the reciever? Where does it connect on the reciever.
I think you mean optical AUDIO out (you said video). It would connect to an optical audio input on the receiver that corresponds to the receiver's input you'll be using to listen to the sound (probably one marked "TV" or "Cable" or "Satellite").
I just checked the back of your box, and it offers both optical audio out AND coax audio out.... use the optical one (requires a special cord - and be careful when plugging them in - they need to be lined up correctly).
Good Luck!