Yamaha Bass Amplifier Musical Instrument Amplifier User Manual


 
6
F-20B
MAIN 1/2
MAIN 2/2
[P100], [C][A120]
[P60][P70][P80]
[A140]
[P70][P60][P40] [P40]
Power Transformer
[A120]: Hexagonal Nut 9.0 12X2 MFNI33 (LX200060)
[A140]: Hexagonal Nut 12.0 14X2 MFNI33 (ES200210)
[P60]: Pan Head Screw 4.0X10 MFZN2BL (V7018000)
[P70]: Hexagonal Nut #1 4.0 MFZN2Y (VB837300)
[P80]: Bind Head Screw-1 3.0X16 MFZN2BL (V7018100)
[P100]: Knob (V6955100)
(Fig. 5)
[P60][P70] [P60][P70]
Power TransformerPower Transformer
(Fig.4)
[P80][P80]
MAIN1/2 Circuuit BoardMAIN1/2 Circuuit Board
MAIN1/2 Circuuit BoardMAIN1/2 Circuuit Board
(Fig. 3)
4. MAIN 2/2 Circuit Board
(Time required: about 3 min)
4-1 Remove the pre-main unit. (See Procedure 1)
4-2 Remove the screw marked [C80]. The MAIN 2/2
circuit board can then be removed. (Fig.3, Fig.5)
5. Power Transformer (Time required: about 4 min)
5-1 Remove the pre-main unit. (See Procedure 1)
5-2 While holding the nuts marked [P70] with a
spanner, remove the two (2) screws marked [P60].
The power transformer can then be removed.
(Fig.4)