Casio DG-20 Player's Manual page 8

CHANGING STRINGS
Move Press Down
1. As shown in the above diagram,
press down on the sensor cover
and move it toward the neck.
Do
not use excessive force on
any parts in the sensor assembly.
Pull String Through Notch and Hole
2. As shown in FIG-1 above,
strings pass through a notch in the
end of the sensor, and then
through a hole in the sensor. After
pulling through a few inches of
string, tie the string as shown in
FIG-2. Next, fix the string tight and
cut off any excess.
3. Insert the accessory hex
wrench (large) into the head and
turn it counter-clockwise to slide
the headpiece towards the body.
Next, insert the other hex wrench
(small) in the headpiece and
loosen the screw.
4. Next, pull the string through
the hole in the headpiece and
tighten the headpiece screw while
pulling the string taut.
Using the large hex wrench, move
slide the headpiece back into
position to adjust string tension.
Avoid tightening the strings
excessively, as this may lead to
neck warps or other damage.
Also, do not use excessive force
on the neck.
Follow the same procedures to
change all 6 strings.
7