SONY TCTX77
Manual de Servicio

SECTION 3 MECHANICAL ADJUSTMENTS
1. PRECAUTION Clean the following parts with a denatured-alcohol-moistened swab: record/playback/earth head pinch roller rubber belts capstan idlers Demagnetize the record/playback head with a head demagnetizer. (Do not bring the head demagnetizer close to the erase head.) Do not use a magnetized screwdriver for the adjustments. After the adjustments, apply suitable locking compound to the parts adjusted. The adjustments should be performed with the rated power supply voltage unless otherwise noted.

SECTION 4 ELECTRICAL ADJUSTMENTS
PRECAUTION 1. The adjustment should be performed in the publication. (Be sure to male playback adjustment at first.) 2. The adjustments and measurement should be performed for both L-CH and R-CH. � Switch position DOLBY NR switch : OFF DIRECTION switch :A � Standard record position Deliver the standard input signal level to input jack and set the REC LEVEL (RV301) control to obtain the standard output signal level as follows. � Record Mode �
AF OSC attenuator 10 k � set LINE OUT 47 k � + �

2.

3. 4. 5.

Torque Measurement Mode Torque Meter FWD FWD Back tension REV CQ-102RC REV Back tension FF, REW CQ-201B CQ-102C

Meter Reading 30 � 65 g�cm (0.42 � 0.90 oz�inch) 1.5 � 6 g�cm (0.021 � 0.083 oz�inch) 30 � 65 g�cm (0.42 � 0.90 oz�inch) 1.5 � 6 g�cm (0.021 � 0.083 oz�inch) 70 � 130 g�cm (0.98 � 1.80 oz�inch)

level meter

600 � LINE IN

Standard Input Level Input terminal source impedance input signal level Standard Output Level Output terminal load impedance output signal level Test Tape Type P-4-A100 P-4-L300 WS-48B 0 dB = 0.775 V Test Mode With the POWER turned OFF, short the test point CN801 (2P) on the SYSTEM CONTROL board (making IC801 pin !º �L�) and turn the POWER ON. Thus, the TEST mode will be activated. If a recording is done in the TEST mode, the REC MEMORY mode becomes active where the tape is rewound by the amount of recording when a rewinding is executed after recording. After adjustment, make the CN801 (2P) open to release the TEST mode. Signal 10 kHz, � 10 dB 315 Hz, 3 kHz, 0 dB 0 dB Used for Azimuth Adjustment PB Level Adjustment Tape Speed Adjustment LINE OUT (L-CH) 47 k� 0.5 V (� 3.8 dB) LINE IN 10 k� 0.5 V (� 3.8 dB)

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