Sony-ST5066-tun-sm 维修电路原理图.pdf

USA, Canada, AEPand UK WodelJSPECI F ICATIONSJFM TUNER SECTIONTuning range:Antenna:Usable sensitivity:S/N ratio:Frequency response:Harmonic distortion:87.5 MHz to 108 MHz300 ohms balanced75 ohms unbalanced2.2pV (lHF)1.7 pV (S/N = 30 dB)68 dB30Hztol5kHz1jOaMono : O.5o/o at 400 Hz 75 kHzdeviation (100%) Mod.Stereo : O.Bo/o at 400 Hz 7 5 kHzdeviation ( l0Oo/o) Mod.Greater than 35 dB at 400 HzFm stereo separation:A-M TUNER SECTIONTuning range: 530 kHz to l,6Ob kHzAntenna: Built-in bar antenna with externalantenna provisionSONfiFtYl STEREO /Ftr.AtvI TllNTNSensitivity:S/N ratio:Harmonic distortion:GENE RA LPower requ irements:Power consu mption:Dimensions:Net weight:48 dB/m, built-in antenna1 00 pV, externa I antenna50 dB at 50 mV/mo.6%120 volts, 60 Hz ac(USA and Canada Model)1 10, 127, 22O, 24O volts, 50/60 Hz ac(AEP and UK Model)23 watts41O (w) x 12O (hl x 284 (d) mmt6r/a (w) x qrr/ro (rr) x 1 13Ao ldl inches4.8 ks (10|b 9 oz)SERtIOE MANUALRadioFans.CN 收音机爱 好者资料库Section1.TABLE OF CONTENTSTitleTECHNICAL DESCRIPTIONDIAGRAMS5-1. Mounting Diagram5-2. Schematic Diagram6. EXPLODED VIEWS7. ELECTRICAL PARTS LISTPagelll315t720l-l. Specificationsl-2. Block Diagram2. DISASSEMBLY AND REPLACEMENT2-l . Front Panel Removal2-5. Printed Circuit Board Removal2-6. Switch ReplacementALIGNMENT AND ADJUSTMENT3-1. Fm I-f and Discriminator Alignment .:. . 63-2. Fm Frequency Coverage and Tracking Alignment . 73-3. Fm Stereo Separation Adjustment 834. A-m I-f Strip Alignment . . 93-5. A-m Frequency Coverage and Tracking Alignment 94. REPACKING3334553.5./VL/RadioFans.CN 收音机爱 好者资料库,Intermediate fre-quency: I O.7 MlzUsable sensitivity: 2.2 pY (IHF)1.1. SPECIFICATIONSFm Tuner SectionTuning range:Antenna:S/N ratio:Capture ratio:Selectivity:Image rejection:I-f rejection:Spurious rejection:A-m suppression:Frequencyresp onse:Harmonicdistortion:Fm stereoseparation:19kHz, 38 kHzsuppression:A-m Tuner SectionTuning range:Antenna:87 .5 to 108 MHz300 ohms balanced75 ohms unbalancedt.7 1tY ( S/N = 30 dB)68 dB1.5 dB55 dB45 dB9s dB75 dB4s dB30Hz to 15 kHz t l OgMono: 0.5 % at 400 Hz 7 5 kHzdeviation (lOO Vo) Mod.Stereo: 0.8% at 400 Hz 7 5 kHzdeviation (lO0Vo) Mod.Greater than 3 5 dB at 400 Hz40 dB530 to 1,605 kHzBuilt-in ferrite bar antenna withexternal antenna provisionSECTION 1TECHNICAL DESCRIPTIONSensitivity:S/N ratio:Image rejection:I-f rejection:Harmonicdistortion:GeneralSignal outputsand impedance:Circuit system:Semiconductors:Power require-ments:tyIntermediate fre-quency: 455 kHz (USA, Canada and AEpModel)468kHz (Uf Model)48 dBlm, built-in antenna100 ltV, external antenna50 dB at 50 mV/m45 dB at I p00 kIIz40 dB at 1,000 kHz0.6%NORMAL 0.7 5Y,4.5 kOHIGH 1.5 V, 3.3 kOat 400 Hz, 100 % Mod.FM stereo, FM/AM superhete-rodyne, switching MPX2 FETs, 20 transistors and 14diodes120 volts, 60 Hz ac (USA andCanada Model)1 10, 127 , 220, 240 volts, 50/60Hz ac (AEP and UK Model)Power consump-tion:Dimensions:Net weight:Shipping weight:23 watts4t0 (w) x 120 (h) x 284 (d) mm16r/d(w) x4tr/ro(h) x ll3/rcG)inches4.8 kg (l0lb 9 oz)6.8kg (l5lb)rIttihItiFTttrIlFtI1-2. BLOCK DIAGRAM()r-d-sir=l.r r ()=OO.=or-f,-l-5rttttaruiosqF*qlraoAvU)alJJsl-f,qtt! !1-Nro8jtJJ k)88jl.|J .E8to.ts5aQroaatlJJl.l.lr-.tu-oqotol-oBta,.t:1*.Pt(OqPoCI99t-L nr4arJv, w,.I2Note: All screws in thisPhillips type (crossotherwisc indicated.SECTION 2DISASSEMBLY AND REPLACEMENTservicc manual arerecess type) unlessAMFMlampFig. 2-3. Dial lamp replacement2.1 . FRONT PANEL REMOVALl. Remove the two screws at both sides of the wood-en case. This frees the wooden case.2. Remove the TUNING knob by pulling it straightoff .3. Remove the two screws from the bottom plateand one screw at both sides of the front subchassisas shown in Fig. 2-l and 2-2. This frees the frontpane1.Fig. 2-1. Front panel removal(bottom view),+.:iFig. 2-2. Front panel removal (side view)2.2. LAMP REMOVALDial Lamp1. Remove the screw shown in Fig. 2-3.This frees the dial lamp holder.2. Remove the lamp from the holder.Meter Lamp1. Straighten the flat spring, then pull it up as shownin Fig. 2-4. This frees the meter lamp holder.2. Remove the lamp from the holder.F ig. 2-4. Meter lamp removal2-3. DIAL CORD STRINGINGPreparationl. Cut a 1250 mm (5l-inch)inch) diameter dial cord.2. Tie the end of the cordFie. 2-5.length of 0.5 mm (l 164-to a spring as shown in3. Rotate the tuning drum fully clockwise (max-imum capacitance position).4. Hook the spring to the tuning drum as shown in.Fie. 2-5.Procedure1. Referring to Fig. 2-5 , proceed the stringing in nu-merical order as shown.Note: Refer to the ltig. 2-6, for wrapping thccord around the druttr.At the finish point of stringing. tiglrtenthe cord so that the spring is undcr tcn-sion, and squeeze the eYelet.2. After completing the dial cord stringing, makesure that the tuning system works properly.3dia I lampflat springmeterlamp holdermeter lampshade3.4.Apply a drop of contact cement to the finishpoint.2.4. FRONT SUBCHASSIS REMOVALPreparationFix the dial cord to the drum and the five pulleysby using a cellophane tape.Remove the tuning drum by removing the setscrew.3. Remove the front panel as described in Procedure2-r.Procedure1. Remove the two screws from the front bottom ofthe chassis as shown in Fig. 2-8.2. Remove the three screws at both sides of theihassis as shown in Fig. 2-9.3. Remove the two screws shown in Fig. 2-10. Thisfrees the front subchassis with dial cordF ig. 2-8.F ro nt su bchassl.s rem ova I(Bottom view)Put the dial pointer onFig. 2-7 , and tune the setMove the dial pointer todial indication coincidescarrier frequency.the cord as shown into the local fm station.the position where thewith the local station1.2.finish point starting PointFig 2-6. Wrapping the dial cordF ig 2-7. D ial pointer installation,.Qthree clockwiseturnstuning drumat fullyclockwise positiond+Finish pointApplya drop ofcontactcem ent-F ig. 2-5. Dial cord stringing4,ikli-Fig. 2-9. Front subcha,ss/s removal(Side view)F ig. 2- I 0. F ront su bchassls remova I2.5. PRINTED CIRCUIT BOARD REMOVALI . Remove the front subchassis as described in Pro-cedure 2-4.2. Remove the four screws shown in Fig. 2-l L Thisfrees the printed circuit board.Fig. 2-l l. Printed circuit board removal2.6. SWITCH REPLACEMENTPushbutton Switch (a-key)l. Remove the printed circuit board as described inProcedure 2-5.2. Remove the switch bracket by removing the twoscrews (P2.6 x 4) shown in Fig. 2-12.3. Remove the screw (P 2.6 x 14) from the bottomas shown in Fig. 2-12.4. With a soldering iron having a solder sucking tip,clean the solder from each lug of the switch.5. Install a new one.- bracketP 2.6x l4Fig. 2-12. 4-key pushbutton switch replacementE,E-=5SECTION 3ALIGNMENT AND ADJUSTMENT3.1, FM I-F AND DISCRIMINATORALIGNMENTCAUTIONThe ceramic filters in the fm i-f circuit areselected according to their specified centerfrequencies and color coded as shownin Fig. 3- l and listed in Table 3- l . Checkthe color code of the filters to identifythe same center frequency when replacingany of these filters.TABLE 3.1.FM I.F CERANIC FILTERSSignal Generator MethodTest Equipment Required1. Signal generator capable of generating a 10.7 MHza-m/fm signal.2. OscilloscopeVertical sensitivity3. Ac VTVM4. Aligpment toolsPreparation:100 mV/cm minimuml. Connect the input cable of the oscilloscope withalligator clips to R 227 and ground on the fm (a-m)front-end/i=f amp/MPX board, and solder a 0.02pFcapacitor across these clips as shown in Fig. 3-3.2. Connect the output cable of the generator acrossCVl02 on the fm (a-m) front-end/i-f amplMPXboard through a 0.02pF coupling capacitor asshown in Fig. 3-4.Fig. 3-3. Fm discriminator output connectionPart No. Colorl-527-220-11 redl-527-220-21 bluel-527-22G31 orangel-527-220-41 blackl-527-22G51 whiteSpecified Center Freq.10.70 MHz10.67 MHz10.73 MHi10.64 MHzlO.7 6 MHzcolor*rFig.3-1. Color dot on ceramic filtercrt03fm ostrimmerFig. 3-2. lnterruption of fm or a-m localoscillator operationNote: Local oscillator should be killed whenperforming this alignment. To stop thelocal oscillator operation, shunt the oscil-lator capacitor with a 0.02pF capacitoras shown in Fig. 3-2.6F ig, 3-4.I 0.7MHz signal iniection=.v-YvProcedure:l. With the equipment connected as shown in Fig.3-5, set the signal-generator controls as follows:Frequency . . Specified frequency ofceramic filter.See Tabte 3- l.Modulation . . Fm,400Hz,75kHzdeviation ( 100%)Output level . . 1,000rrV (60 dB)2. Set the tuner switches as frllows:FUNCTION switch F-MMODEswitch. . MONO3. Adjust the signal generator frequency slightly toobtain a ntaximum output, then change thesignal generator modulation to a-m, 4OOHz 3Wo.4. If the discriminator transformer IFT2OI is notaligned correctly, 400 Hz ripple will be obseryedas shown in Fig. 3-6. I5. Turn the secondary side core of discriminatortransformer IFT20l (see Fig. 3- I 0) to obtaina minimum indication on the oscilloscope with analignment tool as shown in Fig. 3-6.Fig. 3-6. Fm discriminator alignmentoutput responseNote: Turn the core carefully and slowlybecause the output appearing on theoscilloscope jumps up and down whenturning the core. This might cause dif-culty in determining the point of mini.mum output. Also, at both extremepositions of the top coe, decreased out-put will be observed. The real null pointshould be obtained in the middle of thecore thread length, and marimum outputappeas at each side of the true nullpoint.6. Change the signal generator modulation to fm,400 Hz, I5 kHz deviation ( 100%).7 . Turn the core of fm IFTI 0l and the primary sidecore of discriminator transformer IFT201 (seeFig. 3-10) to obtain the maximum output.3.2. FM FREOUENCY COVERAGE ANDTRACKING ALIGNMENTNote: Before startirrg this alignment, the fm i-fand discriminator alignment should beperformed.Test Equipment Requiredl. Fm signal generator2. Ac VTVM3. Oscilloscope4. Alignment toolsPreparation:l. Connect the equipment as shown in Fig. 3-l .2. Set the tuner switches as follows:FUNCTION switch FMMODEswitch.MONOSignal Generator MethodFollow the procedures given in Table 3-2 whenperforming this alignment with an fm signal generator.Be sure that the dial is mechanically calibrated.Off-theAir Signal MethodFrequency coverage and tracking alignment canalso be performed by utilizing off-the-air local fmsignals. However, before performing the alignment,be sure that the dial is mechanically calibrated.Adjust+thFig.3-5. Fm -f and discriminator alignment fesf setup by rf signal generatoroscilloscopeac VTVM0.O2ttFsT-50660.02ttFrfsignalgeneratorr- :JV7fmsignalgeneratorJ I:NTENNANORMALOUTPUTINlr- l.3.3. FM STEREO SEPARATION ADJUSTMENTTest Equipment Requiredl. Fm stereo signal generator2. Ac VTVM3. OscilloscopePreparation:Connect the equipment as shown in Fig. 3-8,set the fm stereo signal generator controls asfollows:Carrier frequency. . . . 98 MHzOutput level . . . . . . 1,000 pV (60 dB)Mode. . . . . . . . . . StgrgoAudio (400 Hz) Mod .6l .5 kHz (90 %) *Pilot ( 19 kHz) Mod . . 7 .5 kHz (10 %)* Note: 75 kHz (1007o) if the metering indicatestotal modulation (audio-pilot).t,YYhocedure:1. Precisely tune the tuner to the carLer frequency yof stereo signal generator, then turn the top coreof switching transformer L301 (see Fie. 3-10) toobtain maximum output at the left channel. Notethat this adjustment has a close relationship withstereo distortion.2. Record the output level of the left channel whenthe stereo signal generator input selector is set tothe left channel.3. Switch the stereo signal generator input selectorto the right channel and read the residual signallevel in the left channel.4. The output-level to residual-level ratio representsthe separation. Adjust separation control RTs0l(see Fig. 3-10) for minimum residual level.Check the right channel for separation. Usually,about an 8 to 9 dB difference in channel separationexists. Readjust RTs0l for minimum differenceFig. 3-7. Fm frequency coverage and tracking alignment test setupTABLE 3.2. FM FREQUENCY COVERAGE AND TRACKING ALIGNMENTFREQLIENCY COVERAGE SG Coupling. DirectALIGNMENT SG Output rvel . 4OOHz,75 kHz Deviation mod; as low as possibleStepSG FrequencyDial SettingAc VTVMConnectionAdiustlndicationI87.5 MHzlowestpositionNORMALOUTPUTOSC coil Ll03See Fig. 3-10.MaximumVTVMreading2108 MHz108 MHzOSC trimmer CTl03See Fig. 3-10.TRACKING ALIGNMENTSGSGCoupling . . DirectOutput Level . 400 Hz, 75kHz Deviation mod; as low as possibleI87.5 MHzTune to theSG signalNORMALOUTPUTAntenna coil Ll0lRF coil Ll02See Fig. 3-10.MaximumVTVMreading2108 MHzAntenna trimmer CT I 0lRF trimrner CT I 02See FiS. 3-10.8AC VTVMsr-5066NORMALoscilloscopefmstereosignat OUTgeneratorNORMAL oi-)OUTPUT (R) Illl- , IqJFig. 3-8. Fm stereo eparation adjustment test setupbetween left- and right-channel separation. rilhile Signal Generator Methoddoing this, remember that the output level alsochanges according to the setting of RT50l. Test Equipment Requiredl. Signal generator2. Loop antenna3-4. A-M l-F STRIP ALIGNMENT 3. Ac VTVM or oscilloscopeNote: The a-m i-f transformers (CFT40I and procedure:IFT4OI) are shipped from the factorywith all adjustments set for correct With the equipment connected as shown inoperation. Therefore no adjustment is Fig.3-9, follow the procedures given in Table 3-3required in field service when performing this alignment with an a-m signalgenerator. Be sure that the dial is mechanicallycalibrated.3.5. A-M FREOUENCY COVERAGE ANDTRACKING ALIGNMENTPreparation:Set the FUNCTION switch to AM.Off-the-Air Signal MethodFrequency coverage and tracking alignment canalso be performed by utilizing off-the-air local a-msignals. However, before performing the alignment,be sure that the dial is mechanically calibrated.ftbFig. 3-9. A-m frequency coverage and tracking alignment test setuploopantennaa-msignalgeneratorl- |AC VTVM9TABLE 3-3. A.M FREQUENCY COVERAGE AND TRACKING ALIGNMENTFREQUENCY COVERAGE ALIGNMENTSG Coupling .SG Output LevelLoop antenna400H2 ,3Vo mod; aslow as possibleStepSG FrequencyDial SettingAc VTVMConnectionAdjustlnd icationI550 kHz5 50 kHzNORMALOUTPUTOSC coil L403See Fig. 3-10.MaximumVTVMreading21,600 kHz1,600 kHzOSC trimmer CT4O2See Fig. 3- l 0.TRACKING ALIGNMENTSG Coupling . .SG Output LevelLoop antenna400H2 ,3Vo mod; as low as possibleI600 kHzTune to theSG signal.NORMALOUTPUTPosition of bar antennaL402. See Fig. 3-10.MaximumVTVMreading21,400 kHzAntenna trimmer CT40lSee Fig. 3-10.Adjustment Parts Location:fm rf trimmercTt 02a-m ant. trimmercT40ta-m osc coilL403fm ant. trimmercrt 0ta-m antennacoil L4O2fm ant. coilLt 0tf m rf coilLt 02fm osc coilLt 03a-m osc fm osctrimmer trimmercT402 CT|03ru:,:*Fig. 3-10. Adjustment parts locationsewrar,)brr,RT50l switch ingtransformerL301fm discriminatortransformer I FT20lfm i-f transformert FTl 0l10SECTION 4REPACKING)t,)The ST-5 06 6s original ship ping carton andpacking materials are the ideal containers for shippingthe unit. However to secure the maximum protection,iT;llr:opo t i s h i n si:,:ik?x;:rtr3-793-107-00 (Canada Model only)3-793-520-00 (UK Model only)Card, warranty3-780-189-ll (AEP and