Yamaha PSR-F50 Service Manual page 9

Rubber Contact
5-4
5-4-1 Remove the white and black keys corresponding to the
rubber contacts to be removed.
(See Fig.4 and Procedure 5-3.)
5-4-2 Remove the rubber contacts. (Photo.2, Fig.5)
5-5 61L Circuit Board
5-5-1 Remove the white and black keys from C1 to B3.
(See Fig.4 and Procedure 5-3.)
5-5-2 Remove the twelve (12) screws marked [90A]. The 61L
circuit board can then be removed. (Fig.5)
5-6 61H Circuit Board
5-6-1 Remove the white and black keys from C4 to C6.
(See Fig.4 and Procedure 5-3.)
5-6-2 Remove the eight (8) screws marked [90B]. The 61H
circuit board can then be removed. (Fig.5)
Fig.5
Photo.2
PSR-F50
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