lexicon m300_sb_970422电路图.pdf

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1、3 Oak Park Bedford, MA 01730 Tel (617) 280-0300, Fax (617) 280-0499 M300 SERVICE BULLETIN Please contact LEXICON CUSTOMER SERVICE with any questions. SB300_970422_00 July 7, 1997 1 SUBJECT: Noise in audio in certain Pitch shift programs (Octave down, Bank 10, Program 2 ) exhibited in some units. REF

2、ERENCE: ECO 970422-00 DISTRIBUTION: International Pro-Product Distributor Service Centers, Customer Service, Repair CORRECTIVE ACTION: The following components must be added and deleted from two of the boards in the M300L. On the HOST board M300L ( Rev 0 to 1 ) Add: 1 W 33 ohm resistor R53 P/N ( 202

3、-00508 ) On the DSP board M300L ( Rev 0 to 1 ) Delete: 1 W 75 ohm resistor R23 P/N ( 202-00512 ) 1 150pF 100V cap C66P/N ( 245-03870 ) EQUIPMENT REQUIRED: Clean, well lighted anti-static work bench with grounded wrist-strap #1 Phillips Screwdriver Low Wattage Soldering Iron Wire strippers Solder Xac

4、to Knife 2” 28 gauge kynar 2” capton tape WARNING This modification should be performed by qualified technical personnel only. Damage caused by performing this modification may void the manufacturers warranty or standard repair policies. CAUTION Electrostatic Discharge (ESD) Precautions The followin

5、g practices minimize possible damage to ICs resulting from electrostatic discharge or improper insertion. Keep parts in original containers until ready for use. Avoid having plastic, vinyl or styrofoam in the work area. Wear a properly installed anti-static wrist-strap. Discharge personal static bef

6、ore handling devices. Remove and insert boards with care. When removing boards, handle only by non-conductive surfaces and never touch open-edge connectors except at a static-free workstation.* Minimize handling of ICs. Handle each IC by its body. Do not slide ICs or boards over any surface. Insert

7、ICs with the proper orientation, and watch for bent pins on ICs. Use anti-static containers for handling and transport. * To make a plastic-laminated workbench anti-static, wash with a solution of Lux liquid detergent, and allow to dry without rinsing. 1. INSTRUCTIONS: The following pages of this bu

8、lletin contain the complete rework instructions for this ECO. RadioFans.CN 收音机爱 好者资料库 3 Oak Park Bedford, MA 01730 Tel (617) 280-0300, Fax (617) 280-0499 M300 SERVICE BULLETIN Please contact LEXICON CUSTOMER SERVICE with any questions. SB300_970422_00 July 7, 1997 2 Please note that these changes ha

9、ve been implemented at the factory starting with M300 serial # 4007 and M300L serial # 1582. Earlier M300 units do not require the change. Implement only in M300 and M300L units with HOST raw PCB p/n 710- 10780,REV0 and DSP raw PCB p/n 710-10800,REV0 AND with serial numbers lower than those indicate

10、d. RadioFans.CN 收音机爱 好者资料库 3 Oak Park Bedford, MA 01730 Tel (617) 280-0300, Fax (617) 280-0499 M300 SERVICE BULLETIN Please contact LEXICON CUSTOMER SERVICE with any questions. SB300_970422_00 July 7, 1997 3 RadioFans.CN 收音机爱 好者资料库 3 Oak Park Bedford, MA 01730 Tel (617) 280-0300, Fax (617) 280-0499

11、M300 SERVICE BULLETIN Please contact LEXICON CUSTOMER SERVICE with any questions. SB300_970422_00 July 7, 1997 4 3 Oak Park Bedford, MA 01730 Tel (617) 280-0300, Fax (617) 280-0499 M300 SERVICE BULLETIN Please contact LEXICON CUSTOMER SERVICE with any questions. SB300_970422_00 July 7, 1997 5 3 Oak Park Bedford, MA 01730 Tel (617) 280-0300, Fax (617) 280-0499 M300 SERVICE BULLETIN Please contact LEXICON CUSTOMER SERVICE with any questions. SB300_970422_00 July 7, 1997 6