320BEE C 320BEE

1 NADSERVICE MANUALC 320 BEESTEREOAMPLIFIERC 320 BEESTEREOAMPLIFIERPRODUCT SAFETY SERVICING GUIDELINES CAUTION : DO NOT ATTEMPT TO MODIFY THIS PRODUCT INANY WAY. NEVER PERFORM CUSTOMIZED INSTALLATIONSWITHOUT MANUFACTURER S APPROVAL. UNAUTHORIZEDMODIFICATIONS WILL NOT ONLY VOID THE WARRANTY, BUTMAY LEAD TO YOUR BEING LIABLE FOR ANY RESULTINGPROPERTY DAMAGE OR USER WORK SHOULD BE PERFORMED ONLY AFTER YOUARE THOROUGHLY FAMILIAR WITH ALL OF THE FOLLOWINGSAFETY CHECKS AND SERVICING GUIDELINES. TO DOOTHERWISE, INCREASES THE RISK OF POTENTIAL HAZARDSAND INJURY TO THE USER. WHILE SERVICING, USE AN ISOLATION TRANSFORMER FORPROTECTION FROM AC LINE CHECKSAFTER THE ORIGINAL SERVICE PROBLEM HAS BEENCORRECTED.

2 A CHECK SHOULD BE MADE OF : FIRE & SHOCK SURE THAT ALL COMPONENTS ARE POSITIONED INSUCH A WAY AS TO AVOID POSSIBILITY OF ADJACENTCOMPONENT SHORTS. THIS IS ESPECIALLY IMPORTANTON THOSE MODULES WHICH ARE TRANSPORTED TO ANDFROM THE REPAIR SHOP. RELEASE A REPAIR UNLESS ALL PROTECTIVEDEVICES SUCH AS INSULATORS, BARRIERS, COVERS,SHIELDS, STRAIN RELIEFS, POWER SUPPLY CORDS, ANDOTHER HARDWARE HAVE BEEN REINSTALLED PERORIGINAL DESIGN. BE SURE THAT THE SAFETY PURPOSEOF THE POLARIZED LINE PLUG HAS NOT BEEN SOLDERING MUST BE INSPECTED TO DISCOVER POSSIBLECOLD SOLDER JOINTS, SOLDER SPLASHES OR SHARPSOLDER POINTS.

3 BE CERTAIN TO REMOVE ALL LOOSEFOREIGN FOR PHYSICAL EVIDENCE OF DAMAGE ORDETERIORATION TO PARTS AND COMPONENTS. FORFRAYED LEADS, DAMAGED INSULATION (INCLUDING ACCORD). AND REPLACE IF NECESSARY FOLLOW ORIGINALLAYOUT, LEAD LENGTH AND NO LEAD OR COMPONENT SHOULD TOUCH A RECEIVINGTUBE OR A RESISTOR RATED AT 1 WATT OR MORE. LEADTENSION AROUND PROTRUDING METAL SURFACES MUSTBE CRITICAL COMPONENTS SUCH AS FUSES,FLAMEPROOF RESISTORS, CAPACITORS, ETC. MUST BEREPLACED WITH EXACT FACTORY TYPES, DO NOT USEREPLACEMENT COMPONENTS OTHER THAN THOSESPECIFIED OR MAKE UNRECOMMENDED AFTER RE-ASSEMBLY OF THE SET ALWAYS PERFORM ANAC LEAKAGE TEST ON ALL EXPOSED METALLIC PARTS OFTHE CABINET, (THE CHANNEL SELECTOR KNOB, ANTENNATERMINALS.)

4 HANDLE AND SCREWS) TO BE SURE THE SETIS SAFET TO OPERATE WITHOUT DANGER OF ELECTRICALSHOCK. DO NOT USE A LINE ISOLATION TRANSFORMERDURING THIS TEST USE AN AC VOLTMETER, HAVING 5000 OHMS PER VOLT OR MORE SENSITIVITY, IN THEFOLLOWING MANNER; CONNECT A 1500 OHM 10 WATTRESISTOR, PARALLELED BY A .15 MFD, 150V AC TYPECAPACITOR BETWEEN A KNOWN GOOD EARTH GROUND(WATER PIPE, CONDUIT, ETC.) AND THE EXPOSEDMETALLIC PARTS, ONE AT A TIME. MEASURE THE AC VOLTAGE ACROSS THE COMBINATIONOF 1500 OHM RESISTOR AND .15 MFD CAPACITOR. REVERSE THE AC PLUG AND REPEAT AC VOLTAGEMEASUREMENTS FOR EACH EXPOSED METALLIC PART. VOLTAGE MEASURE MUST NOT EXCEED 75 VOLTS CORRESPONDS TO MILLIAMP AC ANY VALUEEXCEEDING THIS LIMIT CONSTITUTES A POTENTIALSHOCK HAZARD AND MUST BE CORRECTED : GRAPHIC SYMBOLSSUBJECT : TIPS ON PROPER INSTALLATION1.

5 NEVER INSTALL ANY PRODUCT IN A CLOSED-IN RECESS,CUBBYHOLE OR CLOSELY FITTING SHELF SPACE. OVEROR CLOSE TO HEAT DUCT, OR IN THE PATH OF HEATEDAIR CONDITIONS OF HIGH HUMIDITY SUCH AS:OUTDOOR PATIO INSTALLATIONS WHERE DEW IS AFACTOR, NEAR STEAM RADIATORS WHERE STEAMLEAKAGE IS A FACTOR, AVOID PLACEMENT WHERE DRAPERIES MAY OBSTRUCTREAR VENTING. THE CUSTOMER SHOULD ALSO AVOID THEUSE OF DECORATIVE SCARVES OR OTHER COVERINGSWHICH MIGHT OBSTRUCT WALL AND SHELF MOUNTED INSTALLATIONS USING ACOMMERCAL MOUNTING KIT MUST FOLLOW THE FACTORYAPPROVED MOUNTING INSTRUCTIONS A PRODUCTMOUNTED TO A SHELF OR PLATFORM MUST RETAIN ITSORIGINAL FEET (OR THE EQUIVALENT THICKNESS INSPACERS) TO PROVIDE ADEQUATE AIR FLOW ACROSSTHE BOTTOM, BOLTS OR SCREWS USED FOR FASTENERSMUST NOT TOUCH ANY PARTS OR WIRING.

6 PERFORMLEAKAGE TEST ON CUSTOMIZED CAUTION CUSTOMERS AGAINST THE MOUNTING OF APRODUCT ON SLOPING SHELF OR A TILTED POSITION,UNLESS THE PRODUCT IS PROPERLY A PRODUCT ON A ROLL-ABOUT CART SHOULD BE STABLEON ITS MOUNTING TO THE CART. CAUTION THECUSTOMER ON THE HAZARDS OF TRYING TO ROLL A CARTWITH SMALL CASTERS ACROSS THRESHOLDS OR DEEPPILE CAUTION CUSTOMERS AGAINST THE USE OF A CART ORSTAND WHICH HAS NOT BEEN LISTED BY UNDERWRITERSLABORATORIES, INC. FOR USE WITH THEIR SPECIFICMODEL OF TELEVISION RECEIVER OR GENERICALLYAPPROVED FOR USE WITH S OF THE SAME ORLARGER SCREEN CAUTION CUSTOMERS AGAINST THE USE OF EXTENSIONCORDS, EXPLAIN THAT A FOREST OF EXTENSIONSSPROUTING FROM A SINGLE OUTLET CAN LEAD TODISASTROUS CONSEQUENCES TO HOME AND LIGHTNING FLASH WITH ARROWHEAD SYMBOL, WITHIN ANEQUILATERAL TRIANGLE.

7 IS INTENDED TO ALERT THE USER TO THEPRESENCE OF UNINSULATED DANGEROUS VOLTAGE WITHIN THEPRODUCT S ENCLOSURE THAT MAY BE OF SUFFICIENT MAGNITUDE TOCONSTITUTE A RISK OF ELECTRIC EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE ISINTENDED TO ALERT THE USER TO THE PRESENCE OF IMPORTANTOPERATING AND MAINTENANCE (SERVICING) INSTRUCTIONS IN THELITERATURE ACCOMPANYING THE PRECAUTIONSCAUTION : Before servicing the A/V Receiver covered by thisservice data and its supplements and addends, read and follow theSAFETY PRECAUTIONS. NOTE: if unforeseen circumstancescreate conflict between the following servicing precautions and anyof the safety precautions in this publication, always follow the Safety First:General Servicing Precautions1.

8 Always unplug the A/V Receiver AC power cord from the ACpower source before:(1)Removing or reinstalling any component, circuit board,module, or any other assembly.(2)Disconnecting or reconnecting any internal electrical plug orother electrical connection.(3)Connecting a test substitute in parallel with an : A wrong part substitution or incorrect polarity installationof electrolytic capacitors may result in an explosion Do not spray chemicals on or near this A/V Receiver or any of Unless specified otherwise in this service data, clean electricalcontacts by applying an appropriate contact cleaning solution tothe contacts with a pipe cleaner, cottontipped swab, orcomparable soft specified otherwise in this service data.

9 Lubrication ofcontacts is not Do not defeat any plug/socket B+ voltage interlocks with whichinstruments covered by this service manual might be Do not apply AC power to this A/V Receiver and/or any of itselectrical assemblies unless all solid-state device heat sinks arecorrectly Always connect test instrument ground lead to the appropriateground before connecting the test instrument positive lead. Alwaysremove the test instrument ground lead Checking ProcedureDisconnect the attachment plug from the AC outlet and turn thepower on. Connect an insulation resistance meter(500V) to theblades of the attachment plug.

10 The insulation resistance betweeneach blade of the attachment plug and accessible conductive parts(Note 1) should be more than 1: Accessible Conductive Parts including Metal panels, Inputterminals, Earphone jacks, Sensitive (ES) DevicesSome semiconductor (solid state) devices can be damaged easily bystatic electricity. Such components commonly are calledElectrostatically Sensitive (ES) Devices. Examples of typical Esdevices are integrated circuits and some field effect transistors andsemiconductor chip following techniques should be used to help reduce theincidence of component damage caused by static before handling any semiconductor component orsemiconductor-equipped assembly, drain off any electrostaticcharge on your body by touching a known earth , obtain and wear a commercially availabledischarging wrist strap device, which should be removed forpotential shock reasons prior to applying power to the unit After removing an electrical assembly equipped with ES devices.