Disk Editor?

Can anybody please recommend a (free) disk editor utility that

will allow me to see what file is occupying a particular sector

(on an NTFS drive).

All the utilities I've tried offer only the reverse option, i.e.

will locate the sector if you know the file name but I want to

know what is in sector 197,311 !!

I don't need to actually edit the disk, just find out what the

file name is.

TIA