SONY BM87DST
Service Manual

Pin No. 46 47 48 49 50 � 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 � 80

Pin name LTR-OUT REC-OUT TEL-OUT ALM-OUT KIN 0 � KIN 3 VDD XT1 XT2 NC X1 X2
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I/O O O O O I � I � � I O I I O O I I � I I � At the other : 5.3V DICT, TEL-REC control output. TEL-REC control output.

Description LTR signal output. At LTR oscillating :
5.3V

Output 80Hz for three seconds.

At DICT, TEL-REC : � H �

At the other : � L �

At TEL-REC : � H �

At the other : � L �
5.3V

Alarm output. At alarm oscillating : key scan input.

2.05 kHz

Positiv power source terminal of the microcomputer. Microcomputer operation mode selection input. (Connect to VDD). Not used (OPEN). Not used. Connect to VDD Input for clock oscillation (4.19MHz). Output for clock oscillation (4.19MHz). HU-LISTEN key input. At LISTEN key-in of the hand control unit (HU-80) : � L � At the other : � H � HU-BS key input. At BS key-in of the hand unit (HU-80) : � L � Playback control output. At LISTEN : � H � At the other : � L � At the other : � L � Amplifier mute output. At LISTEN, DICT, TEL-REC : � H � At the other : � H � Foot switch LISTEN key input. At LISTEN key-in of the foot control unit (FS-75) : � L � At the other : � H � Not used (Connect to VDD). HU-LTR key input. At LTR key-in of the hand control unit (HU-80) : � L � At the other : � H � Microcomputer reset input. Normal : � H � Not used (OPEN). At the other : � H �

HU-LIS-IN BS-IN PB-OUT MUTE-OUT FS-IN PR-IN SEC-IN
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HU-FS key input. At FS key-in of the hand control unit (HU-80) : � L �

LTR-IN
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RESET

S0 � S11

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