Yamaha f-20B - Manuals - manualsarea.com

Page 2 - IMPORTANT NOTICE; IMPORTANT NOTICE FOR THE UNITED KINGDOM; IMPORTANT: The wires in this main lead are coloured in accor-; WARNING

2 F-20B IMPORTANT NOTICE This manual has been provided for the use of authorized Yamaha Retailers and their service personnel. It has been assumed thatbasic service procedures inherent to the industry, and more specifically Yamaha Products, are already known and understood by theusers, and have ther...

Page 4 - CIRCUIT BOARD LAYOUT; BLOCK DIAGRAM; Top View

4 F-20B CIRCUIT BOARD LAYOUT MAIN 1/2 MAIN 1/2 MAIN 1/2 MAIN 2/2 MAIN 2/2 AC Cord Power Transformer BLOCK DIAGRAM +B +12V -12V -B GND POWER AMP IC4 IC1 IC3 1 2 3 1 1 4 INPUT FUSE FZ1 ACTIVE TYPE TONE CONTROL POWER SUPPLY CIRCUIT POWER TRANSFORMER 4 Ω Speaker PHONE AUX IN CN2 4P CN1 2P CN3 3P CN4 5P ...

Page 5 - DISASSEMBLY PROCEDURE; MAIN1/2 Circuit Board

5 F-20B DISASSEMBLY PROCEDURE [30] x 4 [60a] [A] BackBoard Speaker Pre-Main Unit Pre-Main Unit (Fig.1) MAIN1/2 Circuit Board Needle-nose plier Needle-nose plier MAIN1/2 Circuit Board [P40] [P40] (Fig. 2) [30]: Truss Head Screw 4.0X25 MFZN2BL (VN347600) [A]: Bind Head Tapping Screw 4.0X25 FCRM3-BL (E...

Page 6 - MAIN1/2 Circuuit Board

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 (VB837...

Page 7 - MAIN1/2 CIRCUIT BOARD; CIRCUIT BOARDS; MAIN2/2 CIRCUIT BOARD

7 F-20B HIGH MID LOW MID BASS AUX IN PHONES POWER to SPEAKER to MAIN 2/2 CN4 from POWER TRANSFORMER to POWER TRANSFORMER from AC CORD to POWER SW A' A INPUT GAIN SELECT VOLUME TREBLE A' A MAIN1/2 CIRCUIT BOARD CIRCUIT BOARDS MAIN 1/2 (J, U, C): CNA-V755470 MAIN 1/2 (H, B): CNA-V755480 MAIN 2/2 (J, U...

Page 8 - Preparation

8 F-20B INSPECTIONS IC BLOCK DIAGRAM BA4558 (XO078A00)Dual Operational Amplifier 1 2 3 4 -V 8 7 6 5 Output A +V Non-Inverting Input A -DC Voltage Supply +DC VoltageSupply Output B InvertingInput B Non-InvertingInput B Inverting Input A + - + - MAIN: IC1,IC2,IC3 1. Preparation To inspect the main uni...

Page 9 - PARTS LIST; BASS AMPLIFIER; CONTENS

F-20B 1 PARTS LIST BASS AMPLIFIER CONTENS OVERALL ASSEMBLY .................................................................................. 2 PRE-MAIN UNIT ............................................................................................ 4 ELECTRICAL PARTS .................................

Page 10 - OVERALL ASSEMBLY; Overall Cabinet Assembly

F-20B 2 OVERALL ASSEMBLY 50 20 10 C40 C60 C50 C60 C50 C30 C30 A C20 C70 C90 C80 40 30 C100 C110 Overall Cabinet Assembly Pre-Main Unit 60 60a

Page 12 - Amp Kit

F-20B 4 A10 A70 A60 A40 A10 A30 A80 A90 A20 P60 P40 P60 P30 P75 P70 P50 P10 P20 P90 P80 A50 P100 P120 P110 A100 A110 A130 A140 A120 Amp Kit P77 PRE-MAIN UNIT

Page 14 - ELECTRICAL PARTS

REF NO. PART NO. DESCRIPTION REMARKS QTY RANK F-20B 6 RANK: Japan only *New parts V 7 5 5 4 7 0 0V 7 5 5 4 8 0 0 V 7 5 5 4 7 0 0V 7 5 5 4 8 0 0 ------ V 6 6 0 9 9 0 0V V 2 9 1 4 0 0U R 8 6 6 1 0 0V Z 3 5 3 5 0 0U R 8 4 7 1 0 0V Z 3 5 3 5 0 0V Z 3 5 3 5 0 0U R 8 6 6 3 3 0V V 0 6 1 2 0 0U R 8 6 5 4 7 ...

Page 16 - OVERALL CIRCUIT DIAGRAM

A B C D E F G H 1 2 3 4 5 F-20B F-20B F-20B <P.1> OVERALL CIRCUIT DIAGRAM Note: See parts list for details of circuit board component parts. TRANS FORMER MAIN 1/2 MAIN 2/2 POWER ON/OFF INPUT AUX IN PHONES J, U, C S, BS 250V 315mA 250V T160mA L WARNING D2SBA20 (VP344100)DIODE STACK 1.5A 200V DB...