Analog Block Replacement - Casio PRT-40C Repair Manual

1) Remove the old piezo from the cover/back (first
take out the piezo from the cover/back using a case
opener A and then clean by wiping with alcohol).
2) Have available the new piezo and the tape/adhe-
sive (thermal compression bonding type).
3) Apply a piece of tape/adhesive to the cover/back
and affix the piezo on the tape. (The piezo should
be positioned so that it contacts the spring/
coil.)
4) With the piezo attached to the tape as in 3) above
and facing up, place the cover/back on a hand
press and apply pressure. Apply pressure by turn-
ing the handle about 180 degree more after the
upper pressing piece of the hand press makes
contact with the piezo.
5) With the piezo and cover/back still in the press, heat the cover/back for about 30 seconds with a
hair-dryer. (Fig. 8-4)
6) When tape/conductive, sheet/insulation and so forth are required following thermal compression
bonding, affix the tape over the piezo.
7) Once the cover/back has cooled, attach it to the watch and check the sound pressure.
8) In the case of water-resistant watches, always make sure to perform the waterproof inspection
after repair is completed.

9. Analog Block Replacement

In the case of modules/with movement in combination watches that use plastic gears, only the analog
portion of the block can be replaced.
Although the replacement procedure in this case differs slightly depending on the model, it generally
consists of the steps described below.
Tool used
NO. Code No.
1 1904 5153 HP-fingerstall (two set)
2 1901 9672 Precision screwdriver set
3 1901 9523 Precision tweezers
4 1904 1647 Anti-mafnetic screw driver set
5 1901 9519 Blower brush
1) Remove the module from the case.
2) Remove the hands, dial, wheel/hour, washer, battery and so forth from the module/with movement.
3) Remove the hooks of the plate/main, and separate the module from the plate/main, housing-1 and
housing-2.
4) Remove the two or three screws to remove the P.C.B. from housing-1.
5) Remove the one or two screws and remove the analog block from housing-1.
6) Replace the analog block with a new one. (Before attaching the new analog block to housing-1,
blow off any dirt or dust with the blow brush.)
7) Reassemble the watch in the reverse order of steps 1) to 5).
Furthermore, the following precautions should be observed when replacing the analog block.
a) Avoid touching the coil ass'y and be careful not break the coil wire.
Tool name
— 24 —
Cover/Back Hand press
Fig. 8-4
Hair drier