Panasonic-RXM50M3G-cs-sm 电路图 维修手册.pdf

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1、nRADIO Frequency Range FM87.5-108 MHz MW520-1610 kHz SW12.3-7.0 MHz SW27.0-22.0 MHz nTAPE RECORDER Track SystemMonaural Recording SystemDC bias, magnet erase Monitor SystemVariable sound monitor Frequency Range65-8000 Hz nGENERAL Power Supply AC110-127/220-240 V, 50/60 Hz Power Consumption8 W Power

2、Consumption In Standby Mode 1.7 W 2006 Matsushita Electric Industrial Co., Ltd. All rightsreserved.Unauthorizedcopyingand distribution is a violation of law. RX-M50M3GU RX-M50M3GC RX-M50M3GS RX-M50M3GS1 Colour (K).Black Type (R).Red Type BatteryDC 6 V (4 UM-1, R20/LR20 batteries) Power Output PMPO18

3、 W (DC 6 V/AC 117 V)2.6 W RMS (Max.)1.6 W Speaker10 cm x 1 Jack OutputEARPHONE; 3.5 mm jack Dimensions (W x H x D) Cabinet Dimensions294.0 x 129 x 99.5 mm Incl. Projecting Parts308 x 137 x 117 mm Mass1.5 kg without batteries 2.0 kg with batteries Notes: 1. Specifications are subject to change withou

4、t notice. 2. Mass and dimensions are approximate. Radio Cassette Recorder Notes: This models cassette tape mechanism unit is SG20. Specifications ORDER NO. MD0603093C3 RadioFans.CN 收音机爱 好者资料库 1 Safety Precautions 3 1.1. General Guidelines 3 1.2. Caution for AC Cord (For GS only) 4 1.3. Before Use 5

5、1.4. Before Repair and Adjustment 5 1.5. Protection Circuitry 5 2 Prevention of Electro Static Discharge (ESD) to Electrostatically Sensitive (ES) Devices 6 3 Warning 7 3.1. Service caution based on legal restrictions 7 4 Accessories 8 5 Operating Instructions Procedures 9 5.1. Main Operation Button

6、s 9 6 Assembling and Disassembling 10 6.1. Caution 10 6.2. Disassembly Procedures 10 6.3. Disassembly Flowchart 10 6.4. Main Parts Location Diagram 11 6.5. Before Disassembly 11 6.6. Disassembly of Front Cabinet 12 6.7. Disassembly of Speaker 12 6.8. Disassembly of Deck Mechanism 13 6.9. Disassembly

7、 of Main P.C.B. 13 6.10. Disassembly of Power P.C.B./Battery P.C.B. 14 6.11. Disassembly Gear Knob 14 6.12. Disassembly for Pointer Guide 14 6.13. Disassembly and assembly for Cassette Compartment 15 6.14. Rectification for tape jam problem 15 7 Service Position 16 7.1. Checking Procedures 16 7.2. C

8、hecking and Repairing of Main, Battery, Mic and Power P.C.B. 16 8 Adjustment Procedures 17 8.1. Tuner Section 17 8.2. Deck Section 19 8.3. Alignment Point 20 9 Wiring Diagram 21 10 Notes of Schematic Diagram 23 11 Schematic Diagrams 25 12 Printed Circuit Board Diagrams 27 13 Illustration of ICs, Tra

9、nsistors and Diodes 29 14 Exploded Views 30 14.1. Deck Mechanism Parts Location 31 14.2. Cabinet Parts Location 33 14.3. Packaging Materials and Accessories 35 15 Replacement Parts List 36 CONTENTS Page Page 2 RX-M50M3GU / RX-M50M3GC / RX-M50M3GS / RX-M50M3GS1 RadioFans.CN 收音机爱 好者资料库 1 Safety Precau

10、tions 1.1. General Guidelines 1. When servicing observe the original lead dress. If a short circuit is found, replace all parts which have been overheated or damaged by the short circuit. 2. After servicing, ensure that all the protective devices such as insulation barriers, insulation papers shield

11、s are properly installed. 3. After servicing, check for leakage current to prevent from being exposed to shock hazards. 1.1.1. Leakage Current Cold Check 1. Unplug the AC cord and connect a jumper between the two prongs on the plug. 2. Using an ohmmeter measure the resistance value, between the jump

12、ered AC plug and each exposed metallic cabinet part on the equipment such as screwheads, connectors, control shafts, etc. When the exposed metallic part has a return path to the chassis the reading should be between 1M and 5.2M. When the exposed metal does not have a return path to the chassis, the

13、reading must be. 1.1.2. Leakage Current Hot Check (See Fig. 1) Fig. 1 1. Plug the AC cord directly into the AC outlet. Do not use an isolation transformer for this check. 2. Connect a 1.5k, 10 watts resistor, in parallel with a 0.15F capacitors, between each exposed metallic part on the set and a go

14、od earth ground such as a water pipe, as shown in Fig. 1. 3. Use an AC voltmeter, with 1000 ohms/volt or more sensitivity, to measure the potential across the resistor. 4. Check each exposed metallic part, and measure the voltage at each point. 5. Reverse the AC plug in the AC outlet and repeat each

15、 of the above measurements. 6. The potential at any point should not exceed 0.75 volts RMS. A leakage current tester (Simpson Model 229 or equivalent) may be used to make the hot checks, leakage current must not exceed 1/2 milliamp. Should the measurement outside of the limits specified, there is a

16、possibility of a shock hazard, and equipment should be examine and reached before it is returned to the customer. 3 RX-M50M3GU / RX-M50M3GC / RX-M50M3GS / RX-M50M3GS1 RadioFans.CN 收音机爱 好者资料库 1.2. Caution for AC Cord (For GS only) 4 RX-M50M3GU / RX-M50M3GC / RX-M50M3GS / RX-M50M3GS1 1.3. Before Use B

17、e sure to disconnect the mains cord before adjusting the voltage selector. Use a minus (-) screwdriver to set the voltage selector (on the rear panel) to the voltage setting for the area in which the unit will be sure. (If the power supply in your area is 220 V to 240 V, set to “220 V to 240 V” posi

18、tion.) Note that this unit will be seriously damaged if this setting is not made correctly. (There is no voltage selector for some countries; the correct voltage is already set.) 1.4. Before Repair and Adjustment DO NOT SHORT-CIRCUIT DIRECTLY (with a screwdriver blade, for instance), as this may des

19、troy solid state devices. After repairs are completed, restore power gradually using a variac, to avoid overcurrent. Current consumption in AC 117 V or 230 V at 50 Hz in NO SIGNAL mode at (volume minimum) should be 60 mA. Battery current consumption (6 V DC) is between 30100 mA. 1.5. Protection Circ

20、uitry The protection circuitry may have operated if either of the following conditions are noticed: No sound is heard when the power is turned on. Sound stops during a performance. The function of this circuitry is to prevent circuitry damage if, for example the positive and negative speaker connect

21、ion wires are “shorted”, or if speaker with an impedance less than the indicated rated impedance of the amplifier are used. If this occurs, follow the procedure outlines below: 1. Turn off the power. 2. Determine the cause of the problem and correct it. 3. Turn on the power once again after one minu

22、te. Note: When the protection circuitry functions, the unit will not operate unless the power is first turned off and then on again. 5 RX-M50M3GU / RX-M50M3GC / RX-M50M3GS / RX-M50M3GS1 2 Prevention of Electro Static Discharge (ESD) to Electrostatically Sensitive (ES) Devices Some semiconductor (sol

23、id state) devices can be damaged easily by electricity. Such components commonly are called Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field-effect transistors and semiconductor “chip” components. The following techniques should be used

24、to help reduce the incidence of component damage caused by electro static discharge (ESD). 1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any ESD on your body by touching a known earth ground. Alternatively, obtain and wear a commercially ava

25、ilable discharging ESD wrist strap, which should be removed for potential shock reasons prior to applying power to the unit under test. 2. After removing an electrical assembly equipped with ES devices, place the assembly on a conductive surface such as aluminium foil, to prevent electrostatic charg

26、e build up or exposure of the assembly. 3. Use only a grounded-tip soldering iron to solder or unsolder ES devices. 4. Use only an anti-static solder remover device. Some solder removal devices not classified as “anti-static (ESD protected)” can generate electrical charge to damage ES devices. 5. Do

27、 not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices. 6. Do not remove a replacement ES device from its protective package until immediately before you are ready to install it. (Most replacement ES devices are packaged with leads electrically shor

28、ted together by conductive foam, aluminium foil or comparable conductive material). 7. Immediately before removing the protective material from the leads of a replacement ES device, touch the protective material to the chassis or circuit assembly into which the device will be installed. Caution: Be

29、sure no power is applied to the chassis or circuit, and observe all other safety precautions. 8. Minimize body motions when handling unpackaged replacement ES devices. (Otherwise harmless motion such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor ca

30、n generate static electricity (ESD) sufficient to damage an ES device). 6 RX-M50M3GU / RX-M50M3GC / RX-M50M3GS / RX-M50M3GS1 3 Warning 3.1. Service caution based on legal restrictions 3.1.1. General description about Lead Free Solder (PbF) The lead free solder has been used in the mounting process o

31、f all electrical components on the printed circuit boards used for this equipment in considering the globally environmental conservation. The normal solder is the alloy of tin (Sn) and lead (Pb). On the other hand, the lead free solder is the alloy mainly consists of tin (Sn), silver (Ag) and Copper

32、 (Cu), and the melting point of the lead free solder is higher approx.30 degrees C (86F) more than that of the normal solder. Definition of PCB Lead Free Solder being used The letter of “PbF” is printed either foil side or components side on the PCB using the lead free solder. (See right figure) Ser

33、vice caution for repair work using Lead Free Solder (PbF) The lead free solder has to be used when repairing the equipment for which the lead free solder is used. (Definition: The letter of “PbF” is printed on the PCB using the lead free solder.) To put lead free solder, it should be well molten and

34、 mixed with the original lead free solder. Remove the remaining lead free solder on the PCB cleanly for soldering of the new IC. Since the melting point of the lead free solder is higher than that of the normal lead solder, it takes the longer time to melt the lead free solder. Use the soldering iro

35、n (more than 70W) equipped with the temperature control after setting the temperature at 35030 degrees C (66286F). Recommended Lead Free Solder (Service Parts Route.) The following 3 types of lead free solder are available through the service parts route. RFKZ03D01K-(0.3mm 100g Reel) RFKZ06D01K-(0.6

36、mm 100g Reel) RFKZ10D01K-(1.0mm 100g Reel) Note * Ingredient: Tin (Sn), 96.5%, Silver (Ag) 3.0%, Copper (Cu) 0.5%, Cobalt (Co) / Germanium (Ge) 0.1 to 0.3% 7 RX-M50M3GU / RX-M50M3GC / RX-M50M3GS / RX-M50M3GS1 4 Accessories AC Cord . (For GC/GU/GS1) AC Cord . (For GS only) AC Adaptor . (For GC only)

37、8 RX-M50M3GU / RX-M50M3GC / RX-M50M3GS / RX-M50M3GS1 5 Operating Instructions Procedures 5.1. Main Operation Buttons 9 RX-M50M3GU / RX-M50M3GC / RX-M50M3GS / RX-M50M3GS1 6 Assembling and Disassembling 6.1. Caution “Attention Servicer” Some chassis components may have sharp edges. Be careful when dis

38、assembly and servicing. 1. This section describes procedure for checking the operation of the major printed circuit boards and replacing the main components. 2. For reassembly after operation checks or replacement, reverse the respective procedures. 3. Select items from the following index when chec

39、ks or replacement are required. 4. Refer to the Part No.on the page of “Parts Location and Replacement Parts List” if necessary. 6.2. Disassembly Procedures Disassembly of Front Cabinet Disassembly of Speaker Disassembly of Deck Mechanism Disassembly of Main P.C.B. Disassembly of Power P.C.B./ Batte

40、ry P.C.B. 6.3. Disassembly Flowchart The following chart is the procedure for disassembly the casing and inside parts for internal inspection when carrying out the servicing. To assemble the unit, reverse the steps shown in the chart as below. 10 RX-M50M3GU / RX-M50M3GC / RX-M50M3GS / RX-M50M3GS1 6.

41、4. Main Parts Location Diagram 6.5. Before Disassembly Important notes: Ensure all the settings as below are set before proceeding to the disassembly steps. Step 1: Set function selector to OFF, band switch to SW2. Step 2: Set tone control and volume control to minimum. Step 3: Set tuning knob until

42、 dial pointer line up at “0” point graduation as shown in the figure. Step 4: Set fine tuning to centre. 11 RX-M50M3GU / RX-M50M3GC / RX-M50M3GS / RX-M50M3GS1 6.6. Disassembly of Front Cabinet Step 1: Remove 6 screws from the back cabinet. Step 2: Press the stop/eject button. Step 3: Remove the fron

43、t cabinet as the arrow shown. Step 4: Remove 4 screws from speaker. 6.7. Disassembly of Speaker Follow (Step 1) - (Step 4) of item 6.6. Step 1: Unsolder the speaker wire. 12 RX-M50M3GU / RX-M50M3GC / RX-M50M3GS / RX-M50M3GS1 6.8. Disassembly of Deck Mechanism Follow (Step 1) - (Step 4) of item 6.6.

44、Step 1: Remove 2 screws from Deck Mechanism. Step 2: Disconnect the connectors (CP2, CN101) and remove the Deck Mechanism. 6.9. Disassembly of Main P.C.B. Follow (Step 1) - (Step 4) of item 6.6. Follow (Step 1) - (Step 2) of item 6.8. Step 1: Pull out the Mic P.C.B. in the direction of arrow and pul

45、l out the tuning knob. Step 2: Disconnect the connector (CP1). Step 3: Pull out 3 knobs and remove 2 switch knobs. Step 4: Remove 6 screws and remove the Main P.C.B. 13 RX-M50M3GU / RX-M50M3GC / RX-M50M3GS / RX-M50M3GS1 6.10. Disassembly of Power P.C.B./ Battery P.C.B. Follow (Step 1) - (Step 4) of

46、item 6.6. Follow (Step 1) - (Step 2) of item 6.8. Follow (Step 1) - (Step 4) of item 6.9. Step 1: Remove 1 screw. Step 2: Remove 3 screws. Step 3: Release the claw in the direction of arrow. Step 4: Release the claw in the direction of arrow and pull out the Battery P.C.B. in the direction of arrow.

47、 6.11. Disassembly Gear Knob Follow (Step 1) - (Step 4) of item 6.6. Follow (Step 1) - (Step 2) of item 6.8. Follow (Step 1) - (Step 4) of item 6.9. Step 1: Release the claw in the direction of arrow and remove the gear knob. 6.12. Disassembly for Pointer Guide Follow (Step 1) - (Step 4) of item 6.6

48、. Step 1: Pull the pointer guides out in the direction of arrow. 14 RX-M50M3GU / RX-M50M3GC / RX-M50M3GS / RX-M50M3GS1 Follow (Step 1) - (Step 4) of item 6.6. Step1: Release the 2 cassette ribs in the direction of arrow. 6.13. Disassembly and assembly for Cassette Compartment 6.14. Rectification for

49、 tape jam problem Note: If cassette tape cannot be removed from the deck since it is caught by the capstan or pinch roller, insert a negative screwdriver with a narrow end into the hole in the rear side of this unit and remove the winded tape while rotating the flywheel assy in the direction of arrow. 15 RX-M50M3GU / RX-M50M3GC / RX-M50M3GS / RX-M50M3GS1 7 Serv