Teac A-300, Service Manual

Page 1: ...plish please contact the nearest TEAC Factory Service Department or write directly to a TEAC office the addresses of which are printed on the back cover of this manual When ordering replacement parts...

Page 2: ...ion vc cg shee eiaiee syoP RSS 8 4 10 Ilder Tension Pulley Ass y 8 Noise reduction circuit made under license from Dolby Laboratories Inc The word Dolby and the Double D symbol are trademarks of Dolby...

Page 3: ...Erase Record and Playback Cassette tape C 60 and C 90 Philips type 4 8 cm s 1 7 8 ips MIC Specified input level 57 dB 1 09 mV 10 kohms Min input level 67 dB 346 uV LINE IN Specified input level 9 dB...

Page 4: ...ge 12 and 16 Playback method 47 dB min Record Playback method BIAS EQ CrO2 45 dB min BIAS EQ NORMAL 44 dB min With Dolby Noise Reduction used for recording and playback S N ratio is improved by up to...

Page 5: ...Ass y Power Transformer REC AND PLAY MECHANISM PCB Ass y AMPL PCB Ass y Damper Holder Ass y DC Motor Ass y Fig 3 1 Top View Cassette Holder Ass y Counter Ass y Supply Take up Reel Table Ass y VU Mete...

Page 6: ...ashers etc 5 To check the shape of assembling hardware screws etc see ASSEMBLING HARDWARE CODING LIST in the parts list 4 1 EXTERNAL PARTS 4 M4x6 Round Washer Head BM3x6 Fig 4 1 External Parts 4 2 CAS...

Page 7: ...the wires to the head terminal pins quickly to prevent breaking of internal wires of the head due to overheating 3 After replacement always clean the driving sur faces of the Pinch Roller with the TE...

Page 8: ...for this purpose For efficient oiling it is recommended that lubrication be done after nearly 1 hour of idling of the deck and while it is still warm Normally it is necessary to lubricate only the ar...

Page 9: ...EW mode and read the pointer indication on the dial scale The Meter should indicate a torque of 80 to 150 g cm 1 1 to 2 1 oz inch as Fast Forward Torque and 100 to 150 g cm 1 4 to 2 1 oz inch as Rewin...

Page 10: ...ake sure the tape path is clean 5 4 2 WOW AND FLUTTER After making the tape speed measurement perform the wow and flutter test using the Playback Method and the Record Playback Method successively PLA...

Page 11: ...pe 2 Make sure the phase relationship between the 2 signals left channel and right channel is within 45 on the oscilloscope Load a TEAC MTT 316 test tape Play the 10 kHz signal section of the tape Adj...

Page 12: ...lay the MTT 150 test tape and adjust R70 R80 for 3 VU indication on the VU Meters 6 1 4 FREQUENCY RESPONSE PLAYBACK 7 Load and play the MTT 316 test tape 8 Play the 315 Hz section of the test tape to...

Page 13: ...35dB 3 dB 9 75 mV to 19 5 mV NOTE To prevent mis measurements for the following procedures any connection cords other than these for the respective input check must be removed For example Do not conne...

Page 14: ...e omitted unless the technician wishes to confirm that they also are within specifications except for the sections where these tape are designated 6 3 1 BIAS TRAP ADJUSTMENTS NOTE The AC Voltmeter use...

Page 15: ...level 2 5dBtidB Obtain 2 5dB 1dB over bias position OUTPUT RESPONSE BIAS CURRENT Fig 6 11 Bias Adjustment 6 3 3 RECORD LEVEL SETTING Cr02 Ts Load a TEAC MTT 506 test tape set the BIAS EQ switches to t...

Page 16: ...nge of the response limits clean the heads and do the L104 L204 Ww NORMAL Tape 6 Repeat the CrO2 procedure with the following ex ceptions BIAS EQ switches NORMAL position Test tape MTT 501 TEST TAPE M...

Page 17: ...at 1 dB 0 869 V for several seconds 0 0 0 0 eee eee 1 3 Rewind the tape to the mid point of the recording and remove the signal from the LINE IN jacks 2 4 Place the deck in the record mode and record...

Page 18: ...eter Numbers in parentheses correspond to steps in Fig 6 18 1 Load a TEAC MTT 506 test tape Fig 6 17 Connection 2 Apply a 1 kHz test tone at 9 dB 275 mV into the left channel Switch Setting oe 4 Rewin...

Page 19: ...20 Adjacent Track Crosstalk Measurement Procedure 6 3 10 DOLBY NR EFFECT MEASUREMENT Specifications Variation from reference at 1 kHz 3dBto8dB Variation from reference at 10 kHz 8 dBto 12 dB Load a T...

Page 20: ...6 C164 C264 L103 L203 L104 L204 TAPE SPEED ADJ 3 000Hz I0Hz Fig 6 21 Adjustment Location Playback Level Playback Frequency Response Meter Calibration Record Level Bias Adjustment Bias Trap Record Freq...

Page 21: ...you AV 1d dOLls 03u AV1d lors lols MAINO _ _ _ ek ee 7 ey yoy 10 1n0 oN mnie 1 CNTENG o 8 5 23Y oe AV Td JOIS av3H i auooay 7 8 an 4700 r ch oI 9010 Y3L3W P ee you nA ee r fH we r 10SW 1020 NIG LLNO N...

Page 22: ..._ NOTES REF Nos shown in the diagram relate only to the left channel 0dB 0 775 V OUTPUT control R71 is positioned at Spec ified Output Level Each level given in the diagram shows values during playbac...

Page 23: ...2 screws in the shorting bar and move the bar so that it shorts across the terminals marked with the desired AC voltage 100 117 220 or 240 After the bar is set to the desired position tighten the scr...

Page 24: ...TOKYO PHONE 0422 53 1111 TEAC CORPORATION OF AMERICA 7733 TELEGRAPH ROAD MONTEBELLO CALIFORNIA 90640 PHONE 213 726 0303 165 167 GLADSTONE STREET SOUTH MELBOURNE VICTORIA 3205 PHONE 699 6000 TEAC AUST...

Page 25: ...1 ee ee ee ees 11 13 1 MODEL 4 DESCRIPTION 2 3 IN OUTPUT PCB eee ee een nee nose mens 11 14 2 REF NO 5 UNIT SERIAL NO 3 PARTS NO 6 MANUAL CODE NO INCLUDED ACCESSORIES 3 NOTICE REGARDING PARTS ORDERS...

Page 26: ...1 EXPLODED VIEWS AND PARTS LIST EXPLODED VIEW 1 TAPTITE M3x6 3 TAPTITE M3x 0 2 M4x6 BLK 2 PSA M26x6 2 W 62 6x97 5 8...

Page 27: ...D AREA 55031841 Cover Assy Cassette B GENERAL EXPORT EUROPE AUSTRALIA U K 1 9 55241240 Spring Earth 1 10 55523500 Panel A U S A CANADA LIMITED AREA 55523510 Panel B GENERAL EXPORT EUROPE AUSTRALIA U K...

Page 28: ...SNhoxe NM2_ SW 2 2 W o _ 4 B M2x3 57 Ye BM2x3 i Ni 4 PSA 6 M2 6x4 g W929 J xB7 xt0 5 aemeea 4 Ni 2 PSA 45 Noe P4x10 25 WO4xt05 e BM26x4 F i PSAM2 6x4 51 al28...

Page 29: ...IPTION Spring Rock Screw Cassette Hoider Holder Assy Cassette Spring Plate Cassette Guide Left Cassette Guide Right Bracket Assy Holder B Holder Cassette B Adhesive Tape Lens Cover Bracket Assy Holder...

Page 30: ...EXPLODED VIEW 3...

Page 31: ...46650 55203430 55551020 DESCRIPTION Clamper Cord A PCB Assy MECHANISM Switch Leaf 1A Switch Leaf 2A Bracket Switch A Bracket Switch Motor Assy DC Bearing Fiywheel Lever Slide Switch Arm Record Plate A...

Page 32: ...LODED VIEW 4 8 2 TAPTITE M3x6 S 2 W O3 5xS8xtl y 2 TAPTITE e M3x6 TAPTITE AF MBx6 _ 2 TAPTITE M3x6 27 FIBERW 38x105 TAPTITE M3x6 o 2 B M3x6 ITE M3x6 eae Ss ee 3 f 2 6 dic 4 SS 20 By E 4l4 2 TAPTITE M3...

Page 33: ...k Killer 0 033 mfd 120 ohm 250V AC Spark Killer 4700 pfd MAX PME271M547 Spark Killer 0 01 mfd 300 ohm 400V AC Var Res 20 kohm Ax2 Bracket Power Switch Rod Power Switch Chassis Front Button D Bracket V...

Page 34: ...2 PC BOARD SECTION Diagram 2 1 REC AND PLAY AMPL PCB i faa 22K ete 10...

Page 35: ...racket All except U S A CANADA AUSTRALIA 4 50 55550620 Plate Selector A Part of 4 51 4 51 51685481 PCB Assy VOLTAGE SELECTOR GENERAL EXPORT LIMTED AREA 51675481 PCB VOLTAGE SELECTOR Part of 4 51 4 52...

Page 36: ...ohm 51815060 10 k ohm 51814820 1k ohm REF NOQ PARTS NO DESCRIPTION R136 R236 51815400 270 k ohm R137 R237 51815220 47 k ohm R138 R238 51815220 47 k ohm R139 R239 51814640 180 ohm R140 R240 51815060 10...

Page 37: ...100 pfd 5OV 10 C143 C243 51713140 Elec 10 mfd 16V C144 C244 51722120 Ceramic 100 pfd 50V 10 C145 C245 51712900 Elec 2 2 mfd 50V C146 C246 51703700 Mylar 0 0056 mfd 50V 5 C147 C247 51703680 Mylar 0 00...

Page 38: ...V 10 50554230 Elec 100 mfd 6 3V 50559420 Elec 1 mfd 50V Bi Polar 50555580 Elec 1000 mfd 25V MISCELLANEOUS 51310300 Switch Slide 6PDT 50529050 Spark Killer 0 1 mfd 120 ohm 400V AC 2 3 IN OUTPUT PCB REF...

Page 39: ...ra x N 57 3 3 Flext 8 g ai sel 13 LB ey 68 zs 8 lox 8 z jw 5 i 750V cl48 sit Qo 2m rd Law s Ee me ca zs EES 8 bea 6027 50 OS partes a 7T22 e 3 108 S Q104 Q105 Rh Weed es NORM Q106 NORMAL 2SC900UA 2SC...

Page 40: ...ype mE Pan Head Screw Stove Head Screw Round Head Truss Tapping Screw A Type Ue inding H e Round Head Binding Head Screw Tanping Sorew B Type Flat Countersunk Hex Socket Head Screw SETSCREW Setscrew F...