CIRCUIT BOARDS ............39 PSR-S750 TEST PROGRAM ........56 PSR-S950 TEST PROGRAM ........63 PSR-S750 SYSTEM BOOTING FLOWCHART ..71 PSR-S950 SYSTEM BOOTING FLOWCHART ..73 PSR-S750 DM CIRCUIT BOARD CHECK METHOD ..75 PSR-S950 DM CIRCUIT BOARD CHECK METHOD ..76 DATA BACKUP .............77 SYSTEM RESET............78 PARTS LIST...
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.
PSR-S750/PSR-S950 SPECIFICATIONS PSR-S950 PSR-S750 Width x Height x Depth (without Music Rest) 1,002 x 148 x 437 mm (39 7/16” x 5 13/16” x 17 3/16”) Size and Weight Weight (without Music Rest) 11.5 kg (25 lbs., 6 oz.) 11 kg (24 lbs., 4 oz.)
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You will need the PRODUCT ID on the sheet in order to fill out the User Registration form. Included Accessories • Music Rest • AC Power Adaptor (PA-300C or an equivalent recommended by Yamaha) This may not be included depending on your particular area. Please check with your Yamaha dealer. AC Power Adaptor...
PSR-S750/PSR-S950 PANEL LAYOUT • Rear Panel PSR-S950 only PSR-S950 only ■ Rear Panel q DC IN jack w [FOOT PEDAL] jacks e OUTPUT [L/L+R]/[R] jacks r [AUX IN] jack t [MIC/LINE IN] jack (PSR-S950) y [INPUT VOLUME] knob (PSR-S950) u [MIC LINE] switch (PSR-S950)
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[MASTER VOLUME] dial !3 [MODULATION] wheel e [DEMO] button !4 [PHONES] jack r [MIC SETTING/VOCAL HARMONY] button !5 [LCD CONTRAST] knob (PSR-S750) !6 LCD and related controls (PSR-S950) t SONG buttons !7 [BALANCE] button y STYLE category selection buttons...
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PSR-S750/PSR-S950 A’ @4 VOICE CONTROL buttons @5 [MUSIC FINDER] button @6 PART SELECT buttons @7 PART ON/OFF buttons @8 REGISTRATION MEMORY buttons @9 MULTI PAD CONTROL buttons #0 ONE TOUCH SETTING buttons #1 UPPER OCTAVE buttons...
PSR-S750/PSR-S950 DISASSEMBLY PROCEDURE Precautions * Disassembly or assembly should be performed on a cloth so as not to damage the LCD. * Install the fi lament tape and the harness clamp in the same way as they were before removal.
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<Rear view> [440D] [440B] PSR-S950 only AJACK <Bottom view> [440C] * This figure shows the PSR-S950. [430B] [430B] [430B] [500A] [430A] [500B] AJACK UPPER CASE ASSEMBLY [430B] [430B] [430B] [440A] [440A] Fig. 3 *1: This figure shows the PSR-S750.
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Remove the lower case assembly. (See procedure 2.) 8-1. Remove the lower case assembly. (See procedure 2.) 6-2. PSR-S750: Remove the eight (8) screws marked 8-2. Remove the screw marked [440E] and the eight (8) [440A]. The DM circuit board can then be removed.
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VOLUME KNOB ENCORDER KNOB [510B] * This figure shows the PSR-S950. CENTER PANEL ASSEMBLY Fig. 5 CENTER PANEL ASSEMBLY CLAWS UPPER CASE ASSEMBLY Fig. 6 ● CENTER PANEL ASSEMBLY (PSR-S750) FFC_S WIRING ASSEMBLY [300A] [300A] [300A] [300A] LCD ASSEMBLY Fig. 7...
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● CENTER PANEL ASSEMBLY (PSR-S950) FFC_S WIRING ASSEMBLY [300B] [300C] [300C] [300B] LCD ASSEMBLY Fig. 8 Crystal Display (PSR-S750) (Time required: About 7 minutes) ● LCD ASSEMBLY (PSR-S750) 9-1. Remove the lower case assembly. (See procedure 2.) <Bottom view> 9-2.
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Fig. 11 fi rst, tighten the screws z and x in that order and then tighten the other screws. that order and then tighten the other screws. PNM Circuit Board (PSR-S750) Keyboard Assembly (Time required: About 10 minutes) 12-1.
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PSR-S750/PSR-S950 PNL Circuit Board PNR Circuit Board (Time required: About 5 minutes) (Time required: About 5 minutes) 15-1. Remove the lower case assembly. (See procedure 2.) 17-1. Remove the lower case assembly. (See procedure 2.) 15-2. Remove the keyboard assembly. (See procedure 14.) 17-2.
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PSR-S750/PSR-S950 Tweeter Speaker Grille Assembly (Time required: About 4 minutes) (Time required: About 5 minutes) 18-1. Remove the lower case assembly. (See procedure 2.) 20-1. Remove the lower case assembly. (See procedure 2.) 18-2. Remove the two (2) screws marked [210]. The tweeter 20-2.
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PSR-S750/PSR-S950 21-6. Rubber Contact Disassembling the Keyboard Assembly 21-6-1. Remove the rubber contact. (Fig. 15) (Photo 2) 21-1. Remove the lower case assembly. (See procedure 2.) 21-2. Remove the keyboard assembly. (See procedure 14.) White and Black Keys 21-7. 21-8. Remove the twenty-one (21) screws marked [140K], EMKS61A Circuit Board 21-3.
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PSR-S750/PSR-S950 22-4. Install the rubber contacts while pulling the keys up. Assembling the Keyboard Assembly (Fig. 17, Fig. 18) 22-1. Install the white keys CEGB from the lower notes. When fi tting the rubber contacts, raise both ends (Fig. 16) of the frame so that keys do not push the rubber 22-2.
PSR-S750/PSR-S950 R8A77310D333BG (YC170A00) SH7731 DM: IC1 (SPR-S950) OUTER OUTER NAME FUNCTION NAME FUNCTION AV33 3.3V power supply for USB reference power supply circuit USB DP pin Ground DG12 1.2V power supply ground for USB driver/receiver XTAL Clock output DG33 3.3V power supply ground for USB driver/receiver...
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PSR-S750/PSR-S950 OUTER OUTER NAME FUNCTION NAME FUNCTION VCCQ I/O power supply (3.3V) Ground PTM7/LCDD7 Port/LCD data bus Ground PTM5/LCDD5 Port/LCD data bus Internal power supply (1.2V) PTM4/LCDD4 Port/LCD data bus Ground PTM3/LCDD3 Port/LCD data bus HPD56/PTN0 SDRAM upper data bus/port...
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PSR-S750/PSR-S950 OUTER OUTER NAME FUNCTION NAME FUNCTION HPDQM0 SDRAM interface lower LL side data mask Chip select HPDQM1 SDRAM interface lower LU side data mask Read signal HPDQM3 SDRAM interface lower UU side data mask WE3/ICIOWR D31 to D24 write/PCMCIA IO write...
PSR-S750/PSR-S950 DM: IC6 (PSR-S750) T6TJ3XBG-0001 ( X8940A00 ) SWP51L ( Tone Generator ) DM: IC601 (PSR-S950) OUTER OUTER NAME FUNCTION NAME FUNCTION VDDC Power supply +1.5 V Ground VDDC HRD2 Ground HRD0 HRD9 CD14 DRAM data bus HRD11 CD13 Data bus of internal register...
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PSR-S750/PSR-S950 OUTER OUTER NAME FUNCTION NAME FUNCTION LMD11 VDDC LMD4 Wave memory data bus (Lower 16 bit) VDDC LMD3 AC10 VDDC Power supply +1.5 V Power supply +3.3 V AC11 VDDC VDDS AC12 VDDC AC13 VDDC AC14 VDDS Ground AC15...
PSR-S750/PSR-S950 μPD720150GK-9EU-A (YD546A00) USB CONTROLLER DM: IC406 (PSR-S950) NAME FUNCTION NAME FUNCTION Ground Oscillator in (Separate mode) Address bus Connect to 30 MHz crystal. (Separate mode) Address bus Oscillator out (Separate mode) Address bus Connect to 30 MHz crystal. (Separate mode) Address bus...
PSR-S750/PSR-S950 S1D13700F01A100 (X5422A00) LCD CONTROLLER DM: IC14 (PSR-S750) NAME FUNCTION NAME FUNCTION – Ground – Ground AB12 XCD1 Drain output AB11 XCG1 Gate input AB10 Adorress bus RESET# Reset SCANEN Test mode set up input TESTEN HIOVDD – Power supply...
PSR-S750/PSR-S950 TMP89FW24AFG-7KH4 (YD841B00) E-PNS3a PNM: IC1 NAME FUNCTION NAME FUNCTION PORT96 PORT52 PORT97 PORT53 VDD pin PORT54 PORT00 PORT55 GND pin PORT56 PORT01 PORT57 Reset signal input PORT60 RESET PORT02 PORT61 PORT03 PORT62 MODE Test pin for out-going test (fix to Low level).
PSR-S750/PSR-S950 YGV628B-VZ (X6356B00) RGB CONTROLLER AVDP7 DM: IC407 (PSR-S950) NAME FUNCTION NAME FUNCTION SA13 Video memory address bus Digital power supply +3.3 V CPU address bus SA11 SA12 Digital power supply +3.3 V Video memory address bus CPU address bus...
PSR-S750/PSR-S950 AK5357ET-E2 (X7585A00) ADC (Analog to Digital Converter) DM: IC510 (PSR-S750) NAME FUNCTION NAME FUNCTION AINR Rch Analog input pin SDTO Audio serial data output pin AINL Lch Analog input pin LRCK Output channel clock pin CKS1 Mode select 1 pin...
PSR-S750/PSR-S950 ISL85033IRTZ-T (YD766A00) DC-DC CONVERTER DM: IC902 (PSR-S950) NAME FUNCTION 1, 21 COMP1, COMP2 COMP1/COMP2 is the output of the error amplifier. 2, 20 FB1, FB2 Feedback pin for the regulator. FB is the negative input to the voltage loop error amplifier.
PSR-S750/PSR-S950 LT3506AEDHD#TRPBF (YC714A00) DC-DC CONVERTER DM: IC502 (PSR-S750) NAME FUNCTION 1, 8 BOOST1, BOOST2 The BOOST pins are used to provide drive voltages, higher than the input voltage, to the internal bipolar NPN power switches. Tie through a diode from V...
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PSR-S750/PSR-S950 PNS Circuit Board Component side 2NA-WZ50830...
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PSR-S750/PSR-S950 PNS Circuit Board Pattern side 2NA-WZ50830...
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PSR-S750/PSR-S950 Scale: 75/100 PNC Circuit Board Component side Pattern side 2NA-WZ55980...
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PSR-S750/PSR-S950 Scale: 75/100 PNL Circuit Board Component side Pattern side 2NA-WZ55980...
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PSR-S750/PSR-S950 Scale: 90/100 PNR Circuit Board Component side Pattern side 2NA-WZ55980...
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PSR-S750/PSR-S950 HP Circuit Board Component side Pattern side MOD Circuit Board Component side Pattern side PB Circuit Board Component side Pattern side 2NA-WZ43510...
PSR-S750/PSR-S950 PSR-S750 TEST PROGRAM If you execute Test No. 43 Factory Set, setting data and user data will be lost. Be sure to save these data for backup in advance. Measurement Conditions 1-1: Measuring Instruments · Level meter (with a JIS-C fi lter).
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001 : Version Checking the version of the ROM. Change the page with TAB [2] [3] switches. [Page 1] PSR-S750 (E) MAIN PROG ROM : * . ** MAIN DATA ROM : * . ** Wave 1 ROM : * . **...
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PSR-S750/PSR-S950 Test No. LCD display Test descriptions, judging conditions, etc. 009 : Output R Check Checking the R channel output. Set the [MASTER VOLUME] control to the maximum position in advance of testing. * It is not possible to operate the VOLUME control while testing.
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PSR-S750/PSR-S950 Test No. LCD display Test descriptions, judging conditions, etc. 017 : SIOF Check Checking SIOF. Have the sound produced from 2 SIOF signal lines (Line-A, Line-B) using the [TAB 2 3] button to check for correct connection. Line-A [TAB 2]: A3 (441 Hz) sound is produced from L channel. “Line-A” is displayed on the LCD.
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PSR-S750/PSR-S950 Test No. LCD display Test descriptions, judging conditions, etc. 028 : Pitch Bend Wheel Check Checking PITCH BEND. When the test is started, “ Pitch Bend Up 128 ” is displayed. Set the [PITCH BEND] wheel to the maximum position and check that the G3 sound is pro- duced and “...
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PSR-S750/PSR-S950 Test No. LCD display Test descriptions, judging conditions, etc. 038 : Backup ROM Check2 Checking the BACKUP ROM connected to the CPU bus. (Complete check) Check that “Backup ROM Check2 OK” is displayed on the LCD. It will take about 1 minute for the check.
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PSR-S750/PSR-S950 Switch Test Sequence (PSR-S750) Turn SW Name / Display Note number Turn SW Name / Display Note number Turn SW Name / Display Note number SELECT SYNC STOP CHOIR & PAD SCORE SYNC START ORGAN FLUTES LYRICS/TEXT START/STOP STRINGS...
PSR-S750/PSR-S950 PSR-S950 TEST PROGRAM If you execute Test No. 47 Factory Set, setting data and user data will be lost. Be sure to save these data for backup in advance. Measurement Conditions 1-1: Measuring Instruments · Level meter (with a JIS-C fi lter).
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PSR-S750/PSR-S950 Tests Overview Test No. LCD display Test descriptions, judging conditions, etc. 001 : Version Checking the version of the ROM. Change the page with TAB [2] [3] switches. [Page 1] PSR-S950 (E) : * . ** MAIN BOOT ROM : *...
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PSR-S750/PSR-S950 Test No. LCD display Test descriptions, judging conditions, etc. 009 : Pitch Check Checking sound pitch. Pitch accuracy check: Connect a frequency counter to the [PHONES] jack. (Either L or R) When the test is executed, a sound is produced with 441 ±0.2 Hz sine wave from the L and R channels.
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PSR-S750/PSR-S950 Test No. LCD display Test descriptions, judging conditions, etc. 017 : SIOF Check Checking SIOF. Have the sound produced from 2 SIOF signal lines (Line-A, Line-B) using the [TAB 2 3] button to check for correct connection. Line-A [TAB 2]: A3 (441 Hz) sound is produced from L channel and muted repeatedly at 1-second intervals.
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PSR-S750/PSR-S950 Test No. LCD display Test descriptions, judging conditions, etc. 027 : LCD Backlight Off Check Checking LCD backlight for ON/OFF function. Switch the backlight ON and OFF with the [TAB 2 3] button. 028 : Main Volume Check Checking the main volume.
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PSR-S750/PSR-S950 Test No. LCD display Test descriptions, judging conditions, etc. 037 : USB to Device/Host Check Checking USB Device/Host. Enter the test with the [START/STOP] button and “Connect Device – Host” will be shown on the LCD. Connect the USB cable to [USB TO DEVICE] and [USB TO HOST] terminals and check that “Device –...
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PSR-S750/PSR-S950 ● Other Tests AUX IN Check that the output is as shown in the following table when signals are input to the AUX IN. OUTPUT (10 kΩ load) PHONES (33 Ω load) OUTPUT INPUT L/L+R AUX IN L: Sine wave (1 kHz, 0 dBu) +7.4 ±...
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PSR-S750/PSR-S950 Switch Test Sequence (PSR-S950) Turn SW Name / Display Note number Turn SW Name / Display Note number Turn SW Name / Display Note number SELECT ENDING/rit.Ⅲ TRUMPET SCORE SYNC STOP CHOIR & PAD LYRICS/TEXT SYNC START ORGAN FLUTES...
PSR-S750/PSR-S950 PSR-S750 SYSTEM BOOTING FLOWCHART If accessing Program Flash doesn’t start, SWX08(IC2) Power ON may be faulty. Accessing Program Flash (IC22) starts. Setting CPU registers. If accessing SDRAM doesn’t start, SWX08 (IC2) may be faulty. Initializing SDRAM for BOOT, 0 clear, setting Accessing SDRAM (IC11, 12) constant.
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PSR-S750/PSR-S950 For example, power turned off while writing Has Factory Reset Is user drive partially been executed? damaged? Improper power shut down! Backup data and/or Userfiles have been lost. Owner name displayed. User drive repaired. Has clearing system backup If failed to reach here, possible cause may be in;...
PSR-S750/PSR-S950 PSR-S950 SYSTEM BOOTING FLOWCHART If accessing Program Flash Power ON doesn’t start, SH7731 (IC1) Main program may be faulty. should exist. Accessing Program Main program not found! Setting CPU registers. Flash (IC16) starts. If accessing SDRAM doesn’t Animation starts.
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PSR-S750/PSR-S950 2nd opening Test mode? Animation to 2nd screen screen displayed. Error Detect pulse output (IC18,1) Has Factory Set been executed? Test mode displayed. Owner name displayed. Data read from NAND (IC202) For example, power turned off while writing. Is user drive...
PSR-S750/PSR-S950 PSR-S750 DM CIRCUIT BOARD CHECK METHOD The DM Circuit Board is provided with test points for service check purposes. Check the test points on the DM Circuit Board if the following symptoms appear. Symptoms and check items q No LCD display with Power SW ON --> Check items 1 to 8 sequentially w No sound or distorted sound -->...
PSR-S750/PSR-S950 PSR-S950 DM CIRCUIT BOARD CHECK METHOD The DM Circuit Board is provided with test points for service check purposes. Check the test points on the DM Circuit Board if the following symptoms appear. Symptoms and check items q No LCD display with Power SW ON --> Check items 1 to 4 sequentially w No sound or distorted sound -->...
This procedure backs up all data saved in USER drive (except Protected Songs and Expansion Voices/Styles) and all settings of the instrument to a USB fl ash memory. Yamaha recommends that you back up important data to a USB fl ash memory since the data in the instrument may be lost on occasion through malfunction or incorrect operation.
PSR-S750/PSR-S950 SYSTEM RESET There are two reset methods in the SYSTEM RESET display: Factory Reset and Custom Reset. Custom Reset (see page 75) Factory Reset (see below) • Factory Reset—Restoring the Factory Programmed Settings This function lets you restore the status of the instrument to the original factory settings.
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PSR-S750/PSR-S950 • Custom Reset—Saving and Recalling Your Original Settings as a Single File For the items below, you can save your Original Settings as a Single File for future recall. Make all desired settings on the instrument. Call up the operation display.
KEYBOARD ASSEMBLY ..........5 UPPER CASE ASSEMBLY ..........6 CENTER PANEL ASSEMBLY .......... 8 LOWER CASE ASSEMBLY ..........10 ELECTRICAL PARTS (PSR-S750)......12–26 ELECTRICAL PARTS (PSR-S950)......27–48 Notes : DESTINATION ABBREVIATIONS A : Australian model M : South African model...
PSR-S750/PSR-S950 CENTER PANEL ASSEMBLY Center panel sub assembly L60a L110 L60a L120 L100 L60a L60a L120 LCD assembly LCD assembly PSR-S750 PSR-S950 only PSR-S950 PSR-S950 only * This figure shows the PSR-S950.
<Page 3> PSR-S750 PSR-S750 DM 003 CIRCUIT DIAGRAM (3/11) SINGLE SHOT to AJACK-CN1 <Page 10: V-7> SYSTEM RESET not installed OP AMP OP AMP to AJACK-CN2 <Page 10: V-4> OP AMP OP AMP REGULATOR +5V DC-DC CONVERTER to AJACK-CN4 DIGITAL AMP <Page 10: P-9>...