COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED LINE WITH MARK 0ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS LIST ARE CRITICAL TO SAFE OPERATION. REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUBLISHED BY SONY.
SECTION 3 DISASSEMBLY The equipment can be remo ved using the f ollo wing pr ocedure . Cabinet (rear) ASSY Main board, Connecter (12P) board Cabinet (front) ASSY LED board Servo board, “Head,magnetic (rec/PB/erase) (HRP901)”, Mechanism deck Motor (F/R) ASSY (M902) Belt (FWD), Belt (F/R) Motor ASSY (FWD) (M901) Note : Follow the disassembly procedure in the numerical order given.
SECTION 4 MECHANICAL ADJUSTMENTS PRECAUTION Forward Torque Adjustment 1. Clean the following parts with a denatured alcohol moistened Torque meter Meter reading Procedure swab : Adjust the forward torque by record/playback/erase head pinch roller 20 to 45 g • cm CQ-102C replace the spacer shown in rubber belts...
SECTION 5 ELECTRICAL ADJUSTMENTS PRECAUTION Tape Speed Adjustment 1. Switches and controls should be to set to the positions as fol- Setup : lows unless otherwise specified. Mode : Playback (LISTEN) • Switch positions POWER switch : ON test tape WS-48 AUTO STOP switch : ON...
SECTION 6 DIAGRAMS 6-1. EXPLANATION OF IC TERMINALS IC109 µPD75308GF-J16-3B9 (SYSTEM CONTROL) Pin No. Pin name Description 1 – 12 S12 – S23 – Not used (OPEN). 13 – 16 KOUT 0 – KOUT 3 Key scan output. MA50 - OUT –...
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Pin No. Pin name Description LTR signal output. At LTR oscillating : 5.3V Output 80Hz for LTR-OUT three seconds. At the other : 5.3V REC-OUT DICT, TEL-REC control output. At DICT, TEL-REC : “ H ” At the other : “ L ” TEL-OUT TEL-REC control output.
BM-87DST 6-4. SCHEMATIC DIAGRAM (SERVO SECTION) Waveform 2.8Vp-p 3.8 msec VOLT/DIV : 0.5 V AC M901 TIME/DIV : 2 msec Note: • All capacitors are in µF unless otherwise noted. pF: µµF 50 WV or less are not indicated except for electrolytics and tantalums.
12P CONNECTOR SECTION 8 SECTION 7 MAIN ELECTRICAL PARTS LIST EXPLODED VIEWS NOTE : 7-2. MECHANISM DECK SECTION (1) 7-3. MECHANISM DECK SECTION (2) NOTE : • Due to standardization, replacements in the • SEMICONDUCTORS • -XX, -X mean standardized parts, so they •...
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BM-87DST REVISION HISTORY Clicking the version allows you to jump to the revised page. Also, clicking the version at the upper right on the revised page allows you to jump to the next revised page. Ver. Date Description of Revision 2000.01...