Bose freespace business music system 278977 service manual rev1

This is the 109 pages manual for bose freespace business music system 278977 service manual rev1.
Read or download the pdf for free. If you want to contribute, please mail your pdfs to info@audioservicemanuals.com.

Page: 1 / 109
left right
bose freespace business music system 278977 service manual rev1

Extracted text from bose freespace business music system 278977 service manual rev1 (Ocr-read)


Page 1

2 CONTENTS Contents ............................................................................................................................................. 2 Safety Information ............................................................................................................................. 3 Warranty ............................................................................................................................................. 3 Product Description .......................................................................................................................... 4 Specifications .............................................................................................................................. 5-10 Electrostatic Discharge Sensitive (ESDS) Device Handling ....................................................... 11 Part List Notes ................................................................................................................................. 11 Amplifier Module Repair Information ............................................................................................11 Packaging Part List, FreeSpace ® E4 Series II Business Music System (see Figure 1) ............ 12 Figure 1. FreeSpace E4 Series II System Packaging View ..............................................................12 Accessory Kit Part List (not shown) .............................................................................................12 Main Part List, FreeSpace E4 Series II Business Music System (see Figure 2) ........................ 13 Figure 2. FreeSpace E4 Series II Business Music System Exploded View ......................................14 Main Part List, E4 Series II Power Supply / Power Amplifier PCB Module (see Figure 3) ....... 15 Figure 3. E4 Series II Power Supply / Power Amplifier PCB Module ................................................15 Electrical Part Lists ................................................................................................................... 16-72 Digital Signal Processor / User Interface PCB Assembly ..................................................... 16-36 E4 Series II Power Supply / Power Amplifier PCB Assembly ............................................... 37-51 FreeSpace 4400 Power Supply / Power Amplifier PCB Assembly ........................................ 52-69 FreeSpace 4400 Power Amplifier Driver PCB Assembly ....................................................... 70-72 Disassembly Procedures .........................................................................................................73-74 Figure 4. E4 II Amplifier Module Assembly .......................................................................................74 Test Procedure Setup ............................................................................................................... 75-76 Test Procedures ........................................................................................................................ 77-80 Troubleshooting ........................................................................................................................ 81-89 Theory of Operation .................................................................................................................. 90-97 Accessories..................................................................................................................................... 98 Figure 5. Flash Memory PCB Component Layout ............................................................................99 Figure 6. DSP PCB Assembly Component Layout ...........................................................................99 Figure 7. Wallplate Sense PCB Assembly Component Layout .......................................................100 Figure 8. Mic Sense PCB Assembly Component Layout ................................................................100 Figure 9. Front Panel Display PCB Assembly Component Layout .................................................100 Figure 10. E4 Series II Upper and Lower Amplifier PCB Assembly Component Layout ................101 Figure 11. FS 4400 Upper Amplifier PCB Top Etch and Component Layout ..................................102 Figure 12. FS 4400 Upper Amplifier PCB Bottom Etch and Component Layout ............................103 Figure 13. FS 4400 Lower Amplifier PCB Top Etch and Component Layout ..................................104 Figure 14. FS 4400 Lower Amplifier PCB Bottom Etch and Component Layout ............................105 Service Bulletin ..................................................................................................................... 106-107 Service Manual Revision History ................................................................................................. 108

Page 2

3 SAFETY INFORMATION 1. Parts that have special safety characteristics are identified by the symbol on schematics or by special notes on the parts list. Use only replacement parts that have critical characteristics recommended by the manufacturer. 2. Make leakage current or resistance measurements to determine that exposed parts are acceptably insulated from the supply circuit before returning the unit to the customer. Use the following checks to perform these measurements: A. Leakage Current Hot Check-With the unit completely reassembled, plug the AC line cord directly into a 120V AC outlet. (Do not use an isolation transformer during this test.) Use a leakage current tester or a metering system that complies with American National Standards Institute (ANSI) C101.1 "Leakage Current for Appliances" and Underwriters Laboratories (UL) UL6500 / UL60065 / IEC 60065 paragraph 9.1.1. With the unit AC switch first in the ON position and then in OFF position, measure from a known earth ground (metal waterpipe, conduit, etc.) to all exposed metal parts of the unit (antennas, handle bracket, metal cabinet, screwheads, metallic overlays, control shafts, etc.), especially any exposed metal parts that offer an electrical return path to the chassis. Any current measured must not exceed 0.5 milliamp. Reverse the unit power cord plug in the outlet and repeat test. ANY MEASUREMENTS NOT WITHIN THE LIMITS SPECIFIED HEREIN INDICATE A POTENTIAL SHOCK HAZARD THAT MUST BE ELIMINATED BEFORE RETURNING THE UNIT TO THE CUSTOMER. B. Insulation Resistance Test Cold Check-(1) Unplug the power supply and connect a jumper wire between the two prongs of the plug. (2) Turn on the power switch of the unit. (3) Measure the resistance with an ohmmeter between the jumpered AC plug and each exposed metallic cabinet part on the unit. When testing 3 wire products, the resistance measured to the product enclosure should be between 2 and infinite MOhms. Also, the resistance measured to exposed input/output connectors should be between 4 and infinite MOhms. When testing 2 wire prod- ucts, the resistance measured to exposed input/output connectors should be between 4 and infinite MOhms. If it is not within the limits specified, there is the possibility of a shock hazard, and the unit must be repaired and rechecked before it is returned to the customer. CAUTION: The Bose ® E4 Series II Business Music System contains no user-serviceable parts. To prevent warranty infractions, refer servicing to warranty service stations or factory service. PROPRIETARY INFORMATION THIS DOCUMENT CONTAINS PROPRIETARY INFORMATION OF BOSE CORPORATION WHICH IS BEING FURNISHED ONLY FOR THE PURPOSE OF SERVICING THE IDENTIFIED BOSE PRODUCT BY AN AUTHORIZED BOSE SERVICE CENTER OR OWNER OF THE BOSE PRODUCT, AND SHALL NOT BE REPRODUCED OR USED FOR ANY OTHER PURPOSE. The Bose E4 Series II Business Music System is covered by a limited 5-year transferable warranty. WARRANTY