IMPORTANT NOTICE This manual has been provided for the use of authorized Yamaha Retailers and their service personnel. It has been assumed that basic service procedures inherent to the industry, and more specifically Yamaha Products, are already known and understood by the users, and have therefore not been restated.
XS250/350 SPECIFICATIONS •General Specifications XS250,XS350 XS250 XS350 Power Output Level (Rated Power) 8 ohm/STEREO 230 W + 230 W 170 W + 170 W 20 Hz~20 kHz 4 ohm/STEREO 350 W + 350 W 250 W + 250 W THD+N= 0.1%...
XS250/350 PANEL LAYOUT Front Panel POWER POWER SIGNAL CLIP PROTECTION CLIP SIGNAL CH A CH B 1 POWER switch and indicator 2 SIGNAL indicators 3 CLIP indicators 4 PROTECTION indicator Rear Panel FILTER CHANNEL B CHANNEL A FREQ. FREQ. –dB –dB...
XS250/350 CIRCUIT BOARD LAYOUT & WIRING Top View SUB 5/5 SUB 2/5 Power Transformer SUB 1/5 XS350 Only SUB 4/5 Front View SUB 3/5 SUB 4/5 Wire color 3NC2-V294020...
XS250/350 DISASSEMBLY PROCEDURE Top Cover SUB7 1/5 Circuit Board 1-1 Remove the nine (9) screws marked [410]. The top cover 3-1 Remove the top cover. (See Procedure 1.) can then be removed. (Fig. 1, 2) 3-2 Remove the six (6) screws marked [80a]. The SUB 1/5 circuit board can then be removed.
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XS250/350 PA7 Unit 9-1 Remove the top cover. (See Procedure 1.) 9-2 Remove the front panel. (See Procedure 5.) 9-3 Remove the four (4) screws marked [250]. The PA7 unit with the chassis can then be removed. (Fig. 4) 9-4 Remove the eight (8) screws marked [130]. The PA7 unit can then be removed.
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XS250/350 11. Rear Assembly 11-1 Remove the top cover. (See Procedure 1.) 11-2 Remove the six (6) screws marked [270]. The rear assembly can then be removed. (Fig. 7) [270] Rear assembly [270] [270] [270] [270]: Bonding Tapping Screw-B 4.0X8 MFZN2BL (VR779900) ...
XS250/350 IC BLOCK DIAGRAM M5238AP (XM085A00) Operational Amplifier +DC Voltage Output A Supply Inverting Output B Input A Non-Inverting Inverting Input A Input B Non-Inverting -DC Voltage Supply Input B...
XS250/350 XS250/350 XS250/350 CIRCUIT BOARDS SUB 1/5 Circuit Board SUB 3/5 Circuit Board to PA-CN406 Components side SUB 4/5 Circuit Board Components side from T101 SUB 2/5-CN103 PA-CN404 from T101 SUB 2/5 Circuit Board Components side SUB 1/5-CN610 SUB 5/5 Circuit Board...
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XS250/350 XS250/350 XS250/350 PA Circuit Board SUB 2/5-CN101 SUB 2/5-CN301 from FAN Components side to SUB 1/5-CN611 to SUB 3/5-CN501 •SX350 3NA-V2899600 1 •SX250 3NA-V2899500 1...
XS250/350 INSPECTIONS A STEREO and PARALLEL Operation Before performing any following adjustments, set the unit as follows: Set the ATTENUATIONS at the MAX. Input terminal: Cannon connector pin 2 is HOT, pins 1 and 3 GROUND. MODE switch: STEREO Output terminal:...
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11. Protection Circuitry Test Check that the relay does not work when you apply a sine wave of +5.0 dBu (XS350), +3.0 dBu (XS250) at 10 Hz to the input and adjust the input level to obtain a clipped output wave form.
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XS250/350 13. Signal Indicator Test When a sine wave of 1 kHz, -23 dBu is applied to the input, SIGNAL indicator should light up. B BRIDGE Operation Before performing any following adjustments, set the unit as follows: 1. Set the ATTENUATIONS at MAX.
XS250/350 POWER AMPLIFIER XS250/350 PARTS LIST CONTENTS OVERALL ASSEMBLY ............. 2 PA UNIT ..................4 ELECTRICAL PARTS ............... 5 Notes: DESTINATION ABBREVIATIONS A : Australian model : Japanese model B : British model U : U.S. model C : Canadian model V : General export model(110V)...
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XS250/350 OVERALL ASSEMBLY 260j UL only 260i 260i 260h 260f 260k 260a 260g 260e 260c 260d 260b...