lexicon m300_sb_005电路图.pdf

3 Oak Park Bedford, MA 01730 Tel (617) 280-0300, Fax (617) 280-0499 M300 SERVICE BULLETIN #5 Please contact LEXICON CUSTOMER SERVICE with any questions. M300_005.BUL June 24, 1993 1 SUBJECT: M300 - Power Supply Heatsink Assembly REFERENCE: ECO 930616-01 PURPOSE: To inform technicians of possible intermittent +5V Digital power supply. Symptoms may include possible: Intermittent initialization. Intermittent lock-up. It is recommended that all M300(s) returned for repair have this corrective action installed as a preventive measure. CORRECTIVE ACTION: Improve mechanical integrity of the +5V Digital regulator and eliminate intermittent voltage fluctuations. EQUIPMENT REQUIRED: 2 - Lexicon P/N 644-01740 WSHR,LOCK,SPLIT,#6 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 following 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 before 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 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. INSTRUCTIONS: Install lock split washers (P/N 644-01740) between the head of the mounting screw(s) (P/N 640-01719) and the regulator case in the mounting of the +5V Digital regulator (P/N 340-07535) on the Power Supply Heat Sink Assembly (P/N 023- 07429). Torque 6-8 in/lbs. for the screw(s). RadioFans.CN 收音机爱 好者资料库