Garrett Metal Detector GTI 1500 Owner's Manual page 23

Discovery
Detection of all metal targets will be
indicated by the appearance of a Target
Cursor on the Upper Scale. A cursor will
appear, as shown below, to indicate every
detected target and will remain for 
seconds or until a new target is detected
(whichever comes first). Desirable targets
will also produce a "beep". In the illustra-
tion below the Target Cursor is located at
9+, which would probably indicate a quar-
ter if Treasure Imaging shows it to be a B-
size target. Locate your target by scanning
back and forth over it to determine where
signals are strongest.
Graphic Target Imaging 1500 - 2