Sanyo DSR-M804 Series Service Manual

Contents

− 2 −SAFETY PRECAUTIONSWARNING:Service should not be attempted by anyone unfamiliar with the necessary precautions for this recording or playbackequipment. The following precautions are necessary during servicing:1. Many electrical and mechanical parts in this recorder havespecial safety-related characteristics for providing protec-tion against shock, fire and other hazards. These charac-teristics often go unnoticed in a visual inspection, and theprotection afforded by them cannot necessarily be ob-tained by using replacement components with higher rat-ings (voltage, wattage, etc.).2. Replacement parts having special safety-related charac-teristics are identified in this manual, and in the schematicdiagrams, by the symbol ! . These components havevalues that are of special significance to product safety.Should any component (identified by the symbol ) needto be replaced, use only the part designated in the partsList. Do not deviate from the specified resistance, wattage,and voltage ratings.3. Before returning the set to the customer, always perform anAC leakage current check on the exposed metallic parts ofthe cabinet, such as terminals, screwheads, metal over-lays, etc. to be sure that the set is safe to operate without thedanger of electrical shock, Plug the AC line cord directly intoa 120 V AC outlet. (Do not use a line isolation transformerduring this check.) Use an AC voltmeter with a sensitivity of5000 ohms per volt (or more) as follows: Connect a 1500ohms, 10 watt resistor, paralleled by a 0.15 mfd, 150 VACcapacitor, between a known good earth ground (water pipe,conduit, etc.) and the exposed metallic parts, one at a time.Measure the AC voltage across the 1500 ohms resistor and0.15 mfd capacitor combination. Reverse the AC plug at theAC outlet and repeat the AC voltage measurements foreach exposed metallic part. The measured voltage mustnot exceed 300 mVrms. This corresponds to 200 μA AC.Any value exceeding this limit constitutes a potential shockhazard and must be corrected immediately.4. Fuse symbol marks.For CANADAFor U.S.A.UNDERWRITERS LABORATORIES StandardCAUTION "Risk of fire-replace fuse as marked"Fuse rating is marked atadjacent fuse.Digital VideoRecorder