teac_a-510_a-500_service_alt_scan (2).pdf

TEAC, Stereo Cassette Deck with Dolby System NOTE If any of the adjustments or repairs seem too compli- cated .or are difficult to accornplish, 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, please refer to the PARTS LIST which is printed separately from this manual and included as an insert. - - . - - - - e- e TEAC CORPORATION $onch Roller Ass y T - 23 Fig. 1-2 Front View Rew ind solenoid FF solenoid Head base (Pause 1 solenoid Pinch roller solenoid T-1722 - - L Fig. 1-3 Rear View of Transport Chassis SPECIFICATIONS ANO SERVICE DATA SPECIFICATIOIUS Track System 2 Heads Type of Tape Tape Speed Input (level and impedance) Outputs (level and load impedance) Equalization Head Configuration Motor Bias Frequency Operation Position Power Requirements Weight 4-track, 2channel stereo Erase and RecordIPlayback Cassette tape, C-60 and C-90 (Philips type) 4.8 cmls (1-718 ips) MIC: Specified input level: -57 dB (1 .O9 mV)/(10 kohms) Min. input level: -67 dB (345 pV) LINE IN: Specified input level: -9 dB (274 mV)/(50 kohms) Min. input level : -19 dB (86 mV) DIN*: Mixinputlevel: -35 dB (13.8 mV) OUTPUT: Max. output level: -3 dB (548 mV)/(50 kohms) Specified output level: -5 dB (435 mV) Headphones: Specified output level: -21 dB (69.0 mV)/(8 ohms) CrOz: 3 1 8 0 s + 7 0 s FeCr: 3 1 8 0 s +70ps NORMAL: 3 1 8 0 s +120ps 112-track, l channel Erase Head 114-track, 2channel RecordIPlayback Head FG Servo Controlled DC Motor 100 kHz Horizontal 100/117/220/240 V AC, 50160 Hz, 29W, 25 W for A-500 (Genera1 Export Model) 117 V AC, 60 Hz, 27 W, 23 W for A-500 (U.S.A./Canada Model) 220 V AC, 50 Hz, 27 W, 23 W for A-500 (Europe Model) 240 V AC, 50 Hz, 28 W, 24 W for A-500 (U.K./Aus. Model) 9 kg (20 lbs.) net Fig. 2-1 Dimmensions SERVICE DATA Mechanical Tape Speed Deviation Tape Speed Drift Wow and Flutter Pinch Roller Pressure Ree1 Torque Fast Winding Time 3,000 Hz + 45 Hz 45 Hz Playback: 0.07% (WRMS) O.l5%(RMS) Record/Playback: 020%(RMS) 350 g to 450 g (12.3 oz. to 15.9 oz.) Take-up: 40 to 60 g.cm (0.6 to 0.8 oz-inch) Supply: 2 to 6 g.cm (0.03 to 0.08 oz-inch) Fast Forward: 80 to 150 g.cm (l .l to 2.1 oz-inch) Rewind: 100 to 150 gcm (l .4 to 2.1 oz-inch) 90 seconds for MTT-501 (C-60) Electrical Frequency Response Signal to Noise Ratio Refer to frequency response limits charts on page 16 and 20. Playback method: NORMAL tape: 48 dB (min.) Record/Playback method: CrOz playback only and record/playback methods. First correct tape speed and wow and flutter using the playback only method. Then measure wow and flutter using record and play- back method. 3. As the measured results may vary with respect to location on tape at which it was taken, three points - at beginning, middle and near the end of the tape - should be measured. The worst case reading must satisfy the specification. 5-5-1 TAPE SPEED 1. Connect test equipment to the deck, except the AF . . osciilator, as shown in Fig.5-5. 2. Set the OUTPUT control on the deck to obtain conve- nient output. 3. Set the EQ switch to the NORMAL position, and then load and play a TEAC MTT-I l1 test tape (3,000 Hz signal is recorded). 4. Using a comrnon slotted screwdriver whose handle is completely insulated from the screwdriver blade, adjust the control located at the rear of the motor for read- ing of 3,000 +- 5 Hz on the frequency counter. NOTE: This tape speed setting should be done after approx. 30 seconds of operating time of the deck. 5. Then, verify that the reading on the frequency counter is within the specified range of 3,000 Hz * 45 Hz, and . the tape speed drift is within 45 Hz at any portion of the tape run. 6. If the tape speed is extremely out of the specification, check the pinch rolier pressure and the tape driving function for correctness, and make sure the tape path is clean. 5-5-2 WOW AND FLUTTER L Fig. 5-5 FREOUENCY COUNTER - LIME IH DEC.K under 1 R I - . . . TEST 7 4.3 Tape SpeedIWow .Ti < , . . 1i,*1 1 W . - - - i . L Fig. 6-1 D.C. Vokage Adjustment 6-3 PLAYBACK PERFORMANCE 6-3-1. RECORDIPLAYBACK HEAD AZIMUTH ADJUSTMENT 1. Load and play a TEAC MTT-150 test tape. 2. Make sure the phase relationship between the 2 signals (left channel and right channel) is within 45 on the oscilloscope. * 3. Load a TEAC MTT-3 16 test tape. 4. Play the 10 kHz signal section of the tape. m 4 AC Voltmster under TEST 0 o Fig. 6-2 Connection 7 - ,.-I 5. Adjust the azimuth adjusting nut for the greatest out- put level. 6. After adjustment is made, apply a drop of locking paint to the adjustment nut. I S i d e I 1 (L)-; R/P Heod Fig. 6-3 Head Azimuth Adjustment Location 0 (IN PHASE) 45 90 180 1-1493 Fig. 6-4 Confirming Phase Relationhip 6-3-2 SPECIFIED OUTPUT LEVEL SETTING 6-33 PEAK LEVEL NIETER CALIBRATION Specification: Specifiedoutput level: -5 dB (436 mV) Maximum output level: -3 dB +2 dB (436 mV to 690 mV) AC Voltmeter Fig. 6-5 Connection 1. Load and play a TEAC MTT-150 test tape. 2. Adjust R10/R20 for 580 mV (-2.5 dB) on AC Volt- meter connected to the Dolby test points. 3. Change the AC Voltmeter connection to the OUTPUT jacks (Fig. 6-6). 4. Set the OUTPUT controls to maximum and confirm that -3 dB +2 dB (436 mV to 690 mV) is obtained at OUTPUT jacks. 5. Set the OUTPUT contro1 so that the output of the channel with the lower reading (L-ch or R-ch) reads -5 dB (436 mV). 6. If there is a distinct level differente (more than 1 dB) between channels. adiust R30 or R40 on the channel . < with thehigher reading toreduce the level to within 1 dB or less of the other channel. 7. The position of the OUTPUT controls will now be set to the specified output level setting. Do not change the setting of these controls for the remainder of this pro- cedure unless otherwise indicated. Specification: O dB W NOTE: The step below can be applied to both conventional type (A-500) and bar-graph type (A-5 10). 8. With the specified setting in paragraph 6-3-2, play the MTT-150 test tape and adjust R15/R25 for O dB indica- tion on the peak level meter. 6-3-4. FREQUENCY RESPONSE - PLAYBACK - 9. Load a TEAC MTT-316 test tape and play the 4th sec- tion of the tape, voice labelled as 315 Hz, and note this reading as a temporary reference level for the following adjustments. 10. While playing the 10 kHz recorded section, adjust R16/ R26 so that 10 kHz gives the same level as the previous reference level in order to keep the higher frequency signals within the given response limits. 11. Then play the required signals for comparision with the playback frequency response limits chart. 12. Check that the readings obtained on the AC voltmeter are within the response limits. NOTE: If the response does not meet the specified re- sponse limits, the head should be checked for accumulated oxide or dirt. If no dirt is found, the W head azimuth should be readjusted. l I I l l i l l l : I I I TEST TAPE : MTT-316 (r0!2 i Fig. 6-7 Playback Frequency Response Limits 1 AC Voltrneter I under TEST 0 o Fig. 6-6 Connection 6-3-5 SIGNAL T 0 NOISE RATIO - PLAYBACK - Specifications: EQ switch, NORMAL: 48 dB (min .) NORMAL 1. Connect the deck and the test equipments as shown in Fig. 6-6. 2. Set the EQ switch to NORMAL position. 3. Load and play a TEAC MTT-150 test tape. 4. Confirm that, by reproducing the 400 Hz test tone on W the tape, the output from the deck is set to the specified output level of -5 dB (436 mV). If not, repeat the pro- cedure in paragraph 6-3-2. O 5. Change the tape to a TEAC MTT-501 test tape com- pletely demagnetized by a bulk tape eraser (such as the TEAC E-2) and play it. 6. Read the indication on the AC voltmeter. 7. Compare the output reading to the specified output level (-5 dB). 8. A difference of 48 dB or more is required. 6-34 HEADPHONE OUTPUT LEVEL CHECKS Specification: -21 dB I 3 dB (48.8 mV to 97 mV) I DECK under TEST I -1 Fig. 6-8 Connection NOTE: An 8 ohm non-inductive resistor should be used as the test load resistor. 1. Load and play a TEAC MTT-150 test tape. 2. Measure the level across the test load resistor. 3. Level shail be -21 dB I 3 dB (48.8 mV to 97 mV). 6-4 MONITOR PERFORMANCE 9 6-4-1 MINIMUM INPUT LEVEL CHECKS Specification: LINE: -19dB +-3dB(61.5mVto123mV) MIC: -67 dB +-3 dB (244 pV to 488 pV) DIN: -35 dB I 3 dB (9.75 mV to 19.4 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 exarnple: Do not connect the Microphone and the DIN cords to respective input jacks when checking for the LINE inputs. 1. Load any recordable tape. 2. Place the deck in the REC PAUSE mode. 3. Set the RECORD controls to maxirnum. 4. Apply a 400 Hz signal at -19 dB (86 mV) to the LINE IN jacks and check for -5 dB +-3 dB (308 mV to 615 mV). 5. If the level difference between channels is more than 2 dB, cut the jumper on the lower reading channel so that the level difference become less than 2 dB. (The output level of the channel whose jumper is cut can be raised to 3 dB) (Minimum Input Level adjustments for the LINE inputs). Fig. 6-10 Jurnper Location OSCILLOSCOPE 6. Set the INPUT switch to MICIDIN. 7. Apply a 400 Hz signal at -67 dB(345uV) to the MIC AMP SPKR jacks and check for -5 dBI3 dB. (Minimum Input OKILLATOR 0 1 9 8 f O 9 e W Leve1 checks for the MIC jack). % P 8. Remove the MIC input and apply a 400 Hz signal at AC Mllmeler -35 dB (13.7 mV) to the input terminds of the DIN connector and check for -5 dB +-3 dB. ATTENUTOR Li* I* DECK ourwl 2 i1 m - 9. For the foilowing tests, set the INPUT switch to LINE. At this time, of course, remove the DIN connector and Fig. 6-9 Connection then connect input signal to the LINE IN jacks. uder TEST i o o - (Minimurn Input Leve1 checks for the DIN inputs). 6-4-2 SPECI F IED RECORD CONTROL SETTING 16.Check that with the PEAK HOLD switch ON and with Specification: Specified input level: -9 dB (274 mV) the RESET switch in AUTO, the displayed level will be held on the display for about 0.5 to 1 seconds. 10- Al a 400 at -9 dB (274 the 17.Check that when the METER switch is in the BRIGHT IN jacks. position, there is a bright display, and that the DIM posi- 11. Set the RECORD controls to obtain a reading of -5 dB tion gives a dirnmer display. (436 mV). 12 Changing the AC voltmeter comection to the DOLBY test point, check that the output leve1 from this is within 6-5 RECORDING PERFORMANCE 580 mV (-2.5 dB). NOTE: Before making any adjustments of the recording 13,At this tirne, the physical position of the RECORD circuit, be sure that ail tests in the preceding controls indicates the Specified RECORD Contro1 Set- performance sections have been accomplished. ting referred to in subsequent procedures. The preceding performance should be properly adjusted, otherwise record calibration will be NOTE: After this setting is done, do not disturb the Speci- inaccurate. fied Control Setting of the RECORD controls unti1 the remaining checks and adjustments are completed. 6-5-1 BIAS TRAP ADJUSTMENTS AC Voltmeter OSCILLATOR e e Fig. 6-11 Connection AC Voltmeter m I QOSC 6-4-3 PEAK LEVEL METER CALIBRATION CHECKS Specification: O dB i l dB Fig. 6-13 Connection NOTE: The AC Voltmeter used in this procedure must have input irnpedance of 1 M oh or more. Fig. 6-12 FL Peak Leve1 Meter (A-510) 6-5-2 RECORD BIAS SETTING 14. With specified RECORD contro1 setting, make certain that the indication on the peak level meter (applicable for both conventional type of A-500, and bargraph type of A-510) on the deck is O dB +l dB. For A-5 10 only 15.Check that when the PEAK HOLD switch is pushed to the ON position, the meter retains (holds) the indicated O dB (or more) level on the display. 1. Connect the deck and the test equipment as shown in Fig. 6-9. 2. Load a TEAC MTT-506 test tape. 3. Place the deck in the record mode. 4. Apply 2 tone signals, in turn; a 400 Hz tone at -42 dB (6.15 mV) and a 10 kHz tone at -42 dB . 5. Rewind and play this recorded section. 6. Compare the differente between the output level of the 400 Hz signals and that of the 10 kHz signal on the AC , Voltmeter. 7. The output level of the 400 Hz signal and that of the 10 kHz signal must be the same value. 8. Adjust C 1421242, If necessary, to achieve this. 9. Continue the process of the recording-rewinding-playing- adjusting until the 400 Hz and 10 kHz signals produce the same output level. NORMAL 10. Set the BIASIEQ switches to NORMAL position and the DOLBY NR switch to IN position. 11. Load an MTT-501 test tape and repeat the above steps 3 to 9 except adjust C143/C243 until the 10 kHz signal level is +4 dB above the 400 Hz signal. B BIAS CURRENT 5 (L 5 O Fig. 6-14 Bias Adjustrnent OPTIMUM VALUE (NORMAL POSITION) 7 FeCr 18.Set the BIASIEQ switches to the FeCr position, and load the MTT-504 test tape. 19.Apply and record a 400 Hz, -8 dB signal and ensure that the output level is within -8 dB 22 dB (245 mV to 388 mV). 6-5-4 DISTORTION CHECKS Specification: 2.0%or less (w/3 types of tape) OPTIMUM VALUE 1 POSITIONI AC Voltrn.1 under TEST o o T.,. 8 Fig. 6-15 Connection CrOn 1. Load a TEAC MTT-506 test tape. 2. Apply and record a 400 Hz test tone at -1 2 dB (194 mV). 3. Rewind and play this recorded section. 4. Read the indicated value on the distortion analyzer. FeCr and NORMAL 5. Repeat the CrOn procedure, with the foiiowing ex- ceptions. FeCr NORMAL BIASIEQ switches: FeCr NORMAL Test tape: MTT-504 MTT-501 6-5-3 RECORD LEVEL SETTING Cr On 12. Load a TEAC MTT-506 test tape, set the BIAS/EQ Switches to the CrOn position and DOLBY NR switch OUT. 13. Apply and record a 400 Hz test signal at -1 2 dB (194 mV). 14. Rewind and play this recorded section. 15. Adjust R12/R22 to obtain -8 dB (308 mV) output level. 16. Continue the process of the recording-rewinding-playing- adjusting until this -8 dB is obtained. NORMAL 17. Regeat the CrOn procedure, set the BIAS/EQ switches to the NORMAL position, use the MTT-501 test tape and adjust R11 /R21. 6-5-5 FREQUENCY RESPONSE - OVERALL - CrOz 1. Connect the deck and the test equipment as shown in Fig. 6-9. 2. Load a TEAC MTT-506 test tape. 3. Apply and record a test signal, containing the necessary frequencies for comparison with applicable Overail Fre- quency Response Limits chart, at -42 dB (6.15 mV). 4. Rewind and play this recorded section. 5. Make sure the readings on the AC Voltmeter are within the response limits. 6. In case of any deviation in the high frequency range of the response limits, clean the heads. 7. If this cleaning is inefeective, recheck whether the re- cording bias setting is correct or not. If wrong, readjust this and then recheck and correct affected procedures. NORMAL 8. Repeat the CrOz procedure, with the following ex- c