Tandberg-3000X-tape-sm 维修电路原理图.pdf

TANDBERGSeries SOOOXSERVICE MANUAL;ir-It ; ll -: ITANDAERGocreCOAO LEELryr;A*qrruct-;TANDBERGS RADIOFABRIKK A/SRadioFans.CN 收音机爱 好者资料库-AaRadioFans.CN 收音机爱 好者资料库.G.ContentsF1.0 TECHNICAL SPECIFICATIONS2.0 MECHANCIAL ADJUSTMENTS2.1 Clutches .:.2.1.1 Take-up Turntable2.1 .2 Take-up Turntable2.1.3 Supply Turntable2.1.4 Supply Turntable2.2 Brakes2.3 Pressure Pad Adiustment . .2.4 End Stop Mechanism .2.4.1 Tape Feeler Tension2.4.2 Adjustment of Tape Feeler3.0 ALIGNMENT .3.1 Demagnetlzing3.2 Blas- and Erase Circuits3.2.1 Oscillator Frequency . . .3.2.2 Erase Voltage3.2.3 Bias Current4.0 TAPE PATH4.1 Visual Check4.2 Mechanlcal adjustment ol tape path . . .5.0 HEAD ALIGNMENT WITH TANDBERG TESTTAPES, MODEL 3041X5.1 Playback head5.1.1 Height Adjustment5.1.2 Azimuth Adjustment5.2 Record Head .5.2.1 Height Adlustment by VisualInspection5.2.2 Height Adjustment by TrackMeasurement . .5.2.3. Azimuth Adjustment .5.3 Bias Head5.3.1 Vertical Adjustment .5.3.2 Height Adjustment5.3.3 Horizontal Adjustment5.4 Erase Head .5.4.1 Height Adjustment5.4.2 Azimuth Adjustment5.5 Model 3021X .6.0 HEAD ALIGNMENT WITHOUT TANDBERGTEST TAPES, MODEL 3041X6.1 Playback Head .6.1.1 Height Alignment6.1.2 Azimuth Alignment . .6.2 Record Head .6.3 Bias Head6.4 Erase Head .6.4.1 Height Adjustment6.4.2 Azimuth Adjustment6.5 Model 3021X .7.0 TRACK CONTROL7.1 Model 3041X .7.1.1 Record Head7.1.2 Erase Head .7.1.3 Playback Head7.2 Modell 3021X .7.2.1 Erase Head .7.2.2 Record Head7.2.3 Playback Head8.0 ADJUSTMENT AND CONTROL OFTHE AMPLIFIERS . 118.1.1 Playback Level Adjustment . 118.1.2 Adjustment of Bias Current . 118.1.3 Record/Playback Level Adiustment 118.1.4 Record/Playback Curves . . 118.1.5 Distortion . 118.1.6 Control of Playback Amplifier . 1l8.2 Tape Speed Control . 128.2.1 Using Frequency Meter or Counter 128.2.2 Using Transformer and VacuumTube Voltmeter . . . 128.2.3 Using Tape of Known Length . 129.0 RECORD/PLAYBACK CURVES . 129.1 Readjustment ol Record/Playback Level 129.2Dlstortlon. .129.3 Control of Playback and RecordAmpliliers . . 129.3.1 Playback Amplifier . . 129.3.2 Record Amplifier . 1310.0 MoDrFtcATroNS . 1510.1 Modilications from 11511301230/240 V,50/60 Hz Operation . . . 1510.2 Modification lrom Four-Track to Two-TrackVersion. .1510.3 Component Modification in Series 3000X 1511. LUBRTCATTON . . 1512.0 ILLUSTRATIONS WITH REFERENCEPART NUMBERS . . 1613.0 SPARE PARTS LIST FOR MODEL 3OOOX . 2213.1 Mechanical Parts . . . 2213.2 Electrica! Components . . . . 2614.0 TABLE OF TRANSISTORS USED INMODEL 3OOOX15.0 BLOCK DIAGRAM FOR MODEL SOOOX . . 2816.0 PRINTED WIRING BOARDS AND WIRINGDIAGRAM16.1 European Version16.2 U.S. Version10101010111111111144444456666777777888II99999I9999II10101010101010101010101028301.0 TECHNICAL SPECIFICATIONSPOWER REQUIREMENTS: 115-130-230-240 V. 50 or 60 Hz operation. See chapter 10.1 for voltageconnections.POWER CONSUMPTION: 45 watts.MOTOR: Asynchronous.TAPE SPEED: 17le ips, 33/r ips and 7tlz ips.TAPE: Maximum reel diameter 7. Low Noise Tape only should be used for recordinqand for adjustment procedure.WINDING TIMES: 1200 ft. of tape; 131 min.1800 ft. of tape: 2t/z min.PLAYING TIME, Two track recording on 1800 ft. of tape.MODEL 3021X: Stereo Mono7t/z ips: 48 min. 2 x 48 min.33/,r ips: 96 min. 2 x 96 min.17la ips: 192 min. 2 X 192 min.PLAYING TIME, Four track recording on 1800 ft. of tape.MODEL 3041X: Stereo Mono71/z ips: 2 x 48 min. 4 x 48 min.33/r ips: 2 x 96 min. 4 x 96 min.17le ips: 2 x 192 min. 4 x 192 min.SPEED TOLERANCE: -+ 1,50/0.HEADS: Separate heads for erasure, recording, playback and bias (Tandberg Cross-field).FREQUENCY RESPONSE: 7t/z ips: 40-20.000 Hz -+ 2dB33/r ips: 50-16.000 Hz -+- 2dB17e ips: 50- 9.000 Hz -+ 2dBMeasured to DIN 45511:7t/z ips: 4O-22.0O0 Hz33/r ips: 40-18.000 Hz17la ips: 40-10.000 HzAmplifier position: 50-18.000 Hz -+ 3 dBERASE AND BIAS 85,5 kHz. Distortion less than 0,5 %.FREQUENCY:INDICATORS: Moving coil meters. Optimum recording level: Deflection up to 0 dB at maxi-mum 3 o/o distortion.AMPLIFIER DISTORTION: Record Amplifier: Recording of a 400 Hz signat at 0 dB level, gives less than0,5 0/o distortion from recording amplifier.Playback Amplifier: 0,3 0/o distortion at 0, 75 V output voltage.TAPE DISTORTION: A tape recorded with a 40O Hz signal at 0 dB level, gives less than 30/o tapedistortion in playback.A tape recorded with a 400 Hz signal 8 dB below 0 dB on indicator, gives lessthan 0,8 0/o tape distortion in playback.WlclAC!(fi(i-aWOW: W. R. M. S.:7t/z ips - better than 0,07 o/o33/r ips - better than 0,140/o17le ips - better than 0,280/oDtN 45511 :71/z ips - better than 0,1 o/o33/r ips - better lhan O,2o/o17le ips - better than 0,40loCROSSTALK At 1OOO Hz:ATTENUATION: Mono ) 60 dB Stereo ) SO OAINPUTS: Each channel has the following inputs:1. Microphone input for dynamic low impedance microphone. lmpedance:200-700 ohm. Sensitivity at 400 Hz: 0,1 mV. Maximum input level: 25 mV.DIN socket. US-version, Telephone jack.2. Line input for high impedance source. lmpedance: 1 Mohm. Sensitivity at400 Hz: 100 mV. Maximum input level: 20 V. Phono sockets, LINE lNpUTS.3. Line input for low impedance source. lmpedance: 57 kohm. Sensitivity at400 Hz: 5 mV. Maxirnum input level: 1 V. DIN socket RADIO: Pin 1, leftchannel: Pin 4, right channel. US-version: Phono sockets LOW lN.OUTPUTS: Emitter follower outputs, RADIO DIN socket pins 3 and 5. US-version: phonoSocKetS, OUTPUT LEFT and RIGHT.Minimum load impedance: 100 ohm. Output level: A tape recorded with 400 Hzsignal at 0 dB level, gives approx. 0,75 V in playback. HEADPHONES, stereojack for connection of headphones.Stereo jack is connected in parallel with RADIO socket pins 3 and 5. On US-version stereo jack is connected parallel with phono sockets OUTPUT LEFTand RIGHT.SfGNAL TAPE/NOISE Peak value measured according to DIN 45511 at tape speed 71/z ips and 5oloWEIGHTED tape distortion:(GERAUSCHSPANNUNG): 4-track 2-track54 dB 56 dBSIGNAL TAPE/NOISE Peak value measured according to DIN 45511 at tape speed 7t/z ips and 5o/oUNWEIGHTED distortion:(FREMDSPANNUNG): 4-track 2-track51 dB 51 dBSIGNAL/TAPE NOISE: Measured linear R.M.S. at tape speed 7lz ips and 5 o/o distortion:4-track 2-track57 dB s7 dBSfGNAL/TAPE NOISE: Measured at tape speed 7t/z ips and 5 0/o distortion:Wetonreo 4-track z-track(lEC A-CURVE) R. M. S.: 62 dB 64 dBNote: At 3 0/o distortion all signal to noise ratio measurements (Signal/tapenoise) are reduced by 2 dB.DfMENSIONS: Length: 151/2 (39,4 cm), heigth: 6t/2 (16,5 cm) and depth: 123la (31,6 cm).WEIGHT: 20 lbs (9,1 kg).2.0 MECHANICAL ADJUSTMENTS2.1 GlutchesControl of Winding TorqueNote: All controls and measurements must be car-ried out with the tape recorder placed inhorizontal position and with empty reels only.All controls are accomplished as shown intig. 2.2 which presents two optimal modes ofcontrol. Take-up turntable is shown. By con-trol of supply turntable, reverse the figure.2.1.1 Take-up TurntableNormal Forward Winding TorqueSet the operating lever to Normal Forward driveposition v.rith the motor running. The torque is readin table tig. 2.3, pos. 1. Ensure that the clearance991017 9910r3 261841 2673?38 2640834 991009Fig. 2.1 .between the polyurethane friction pads under theturntable and friction disc 991009 lays between0,5-O,9 mm (0.02-0.035). lf necessary, adjustscrew A as shown in fig. 2.1.2.1.2 Take-up TurntableFast Forward Winding TorqueThe torque is read in table fig. 2.3, pos. 3. lf thetorque deviates from the specifications in the table,check and, if necessary, alter the pressure of spring263737B.Ensure that there is a clearance between the studson bushing 2640834 and lever 991013. See fig. 2.4.2.1.3 Supply TurntableTape TensionThe torque is read in table fig. 2.3, pos 2.2.1.4 Supply TurntableFast Reverse Winding TorqueThe torque is read in table fig. 2.3, pos. 3. lf thetorque deviates lrom the specifications in the table,check and, if necessary, alter the pressure of spring2618054. See fig. 2.5.The difference between Fast Winding Torque andFast Reverse Winding Torque should be less than1309 (measured at 30 mm radius), or 509 (measuredat 80 mm radius). lf necessary, alter the pressure otspring 261805A (fig. 2.5), or spring 2673738 (fig. 2.1).*1Pot2Pot3,lIaIi(itt0.5 - 0,9mm(0.02t - 0.035r )30 mm radius80 mm radiusFig2.2.Table for Winding TorquesTorque at30 mmradiusTorque at80 mmradius159- 309-tit windingPos2 tape rensronFast windingFig. 2.3.* After a longer periode of continuous operation, anincrease of the torque by 2G-30 0/o is consideredas normal. CEnsure that the torque is within the specificationsin the table by running the tape recorder in verti-cal position, and with a tull 7 reel on take-upturntable.o- 8gPos3909-250gtI264930 991 01 ?Fig. 2.6.2.2 BrakesSee fig. 2.6Set the operating lever to Normal Forward driveposition. Check that the clearance between thebrake pad and the turntable is approx 1 mm (0.04).lf necessary, adjust screw D.Set the operating lever to Fast Forward Winding orFast Reverse Winding position respectively. Ensurethat the clearance between screw C and the bottomof the hinged delrin parts on operating arm 991017lays between 0,5-1 mm (0.02-4.O4 ). lf necessary,adjust screw C.The adjustment procedure is equal for both turn-tables.251489 AFig. 2.7.min 0,lmm(0.004,)Fig. 2.4.261 805AFig. 2.5.2.3 Pressure Pad AdjustmentSet the operating lever to Neutral position. Theclearance between the pressure pad 990325 and thetape rest 254844A should be approx. 6,5 mm (tlr) asshown in fig. 2.7. lf necessary, adlust the clearanceby bending the arm 254025 with a pair of pliers.See fig. 2.8.Fig. 2.8.Set the operating lever to Normal Forward driveposition. The pressure at the pad against the taperest should be 80 g (2,8 ozl -+ 10 0/0, measured on theend of the pressure pad arm 254025. See fig. 2.9.lf necessary, adjust the pressure by bending thespring 268062 with a pair of pliers. See fig. 2.10.2.4 End Stop Mechanism2.4.1 Tape Feeler TenslonThe feeler tension against the tape should lay be-tween 8 and 10 g (0.28-0.35 oz) in drive windingmodes. Adjustment of the tension is accomplishedby tightening or slackening the spring 243990. Seelig. 2.12.Fig.2.10.2.4.2 Adjustmenl of Tape FeelerSee fig. 2.11 and 2.12.Set the operating lever to Normal Forward drive posi-tion. The mains switch is set to ON. No tape shouldbe inserted. The tape feeler will therefore rest in theposition where the motor is switched off. Push thefeeler slowly through the guide post. When the rearside of the feeler is min. 0,5 mm (0.02) from thepolished tape contact surface of the guide post,loosen screw F, and move the microswitch slowlyuntil the motor starts when the tape feeler is in theposition specified above. Then tighten the screw.When the tape feeler is released, the microswitchshould open, and switch off the motor current whenthe space between the tape feeler and the arm266741 is minimum 0,5 mm (O.O2). See fig. 2.12.Check the switching on and-off positions of thetape feeler at both fast winding modes.Il1a(taIazzl/:(,12.82 ozl !l,a-,-/80s252754tM3l4Fig. 2.9.Adjustment distanceJuste ringsavstandminimum 0,5 mm (0,02rr)266741Min 0,5 mm(o.02 lFig. 2.12.243990Fig. 2.11.3.0 ALIGNMENTIt is important that the contact between the tapeand the heads on the tape recorder is good. Toobtain optimum results on new tapes (Low Noise),the tape should be run through the tape recorderapprox. 5 times at normal speed to have the tapepolished before measuring the frequency responseand the signal-to-noise ratio.v 3.1 DemagnetizangDemagnetize the heads and adjacent parts beforealigning the heads.Move the demagnetizing coil slowly past the headgap at short distance. The head surface must on noaccount be touched, as scratches are detrimental tothe performance. Hold the demagnetizing coil nearthe capstan for a few seconds.Start the tape recorder and hold the demagnetizingcoil right above the flywheel.Note: Do not switch off the demagnetizer until it isat least 3 feet away from the tape recorder.3.2 Bias- and Erase Circuits3.2.1 Oscillalor FrequencyConnect a calibrated long wave receiver (tuned to256.5 kHz), frequency meter or frequency counter tothe oscillator by means of a pick-up loop placedaround the erase head. Adjust the oscillatorfrequency to 85.5 kHz by means of C 508.3.2.2 Erase VoltageSet the tape recorder for stereo recording andconnect a VTVM to upper half of the erase headby means of a low-capacitance probe. The voltageshould be 80-120 V. Then check ihat the samevoltage appears across lower head-half.Set the tape recorder for recording on channel Land check the voltage across upper half of theerase head. The deviation from the voltage measuredin stereo recording should not exceed 10 V. Proceedsimilarly for recording on channel R.3.2.3 Bias CurrentSet the tape recorder for stereo recording andmeasure the voltage across upper half of the biashead by means of a VTVM. Adjust the voltage to22 Y by means of R 501 . Check the voltage acrosslower head-half and adjust to 22 Y by means ofR 502. Demagnetize heads and tape path.4.0 TAPE PATH4.1 Visual CheckLoad the recorder with a tape, and move theoperating lever slowly to the normal forward driveposition. Check that the bias head neither touchesthe height adjustment screws (C) on the recordhead base plate, nor presses the tape against therecord head. Also check that the bias head isparallel to the record head.Operate the start/stop knob, and check that thetape runs within the rims of the pressure wheelrubber without flickering on neither side of thepressure wheel. Check that height positioning ofthe guide posts is correct. lt can be tolerated thatthe tape touches the flanges of the guide postswhen the recorder is in normal forward drive, oras the drive mechanism is engaged. The tape must,however, by no means bulge at the flanges.4.2 Mechanical Adjustment of Tape PathPrior to the electrical adjustment of the heads, it isessential to make the tape run without sidewaysmovement through the path.Put a tape free from damages on the recorder innormal way and set the operating lever to normalforward drive position. Adjust the azimuth positionof pressure roller 990334 with a screw driver asshown in tig. 4.2, until the tape is running evenlythrough the rest of the tape path, slightly touchingone of the flanges of the guide post 1 locatedadjacent to the capstan.Align guide posts 2, 3, and 4 similarly. lf necessary,adjust pressure roller spring 234478 to make the taperun perfectly.990334Fig. 4.2. Azimuth adiustment ol pressure roller.(5$,atc5.Pplalalhroeltt5,PpabirE5Irfttthnvtt4IFC(cvI(IIIMDFig. 4.1 . Tape path adiustment screws.rg)d5.0 HEAD ALIGNMENT WITHTANDBERG TEST TAPES,MODEL 3041X5.1 Playback HeadSet the recorder for stereo playback and connecta VTVM to each one of the outputs. Output selectorto position STEREO.5.1.1 Helght AdiuslmentPlay Tandberg test tape No. 1. This is a full trackprerecorded tape with 1.000 Hz recorded at 71/z ips,and with area corresponding to track 3 reduced byapprox. 30 dB. Adjust the height of the playb