Sherwood R-725/RDS Service Manual page 10

3. Block Diagram
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4. Key Matrix
Key Scan 2] Key Scan 3} Key Scan 4| Key Scan 5 | Key Scan 6 | Key Scan 7| Key Scan 8 | Key Scan 9| Key Scani0}Key Scan11
Pin 80 Pin 79 Pin 78 Pin 77 Pin 76 Pin 74
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F : Tape2, , Rear Level
F : Video Center Cinema Rear Level :
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