iv
Model 280B
CONTENTS
(Continued)
Page
SECTION 6.
THEORY
OF OPERATION (Continued) .
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6-1
6.3
PLAY MODE
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, 6-1
6.4
SYNC MODE
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, 6-1
6.5 SQUELCH CIRCUIT
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" 6-1
6.6
TAPE
TRANSPORT
ASSEMBLY.
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, 6-1
6.7 CONST ANT
TENSION.
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6-1
6.8
TRANSPORT
LOGIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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6-1
SECTION 7.
MAINTENANCE.........................
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7-1
7.1 MECHANICAL ADJUSTMENT
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7-1
7.2 BRAKE ADJUSTMENT
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7-1
7.3
Tape
Head Assembly
Adjustments
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7-1
7.4
Motion Sense
Adjustment
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7-3
7.5
Tension Posts
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7-3
7.6
Pinch Roller
Adjustment
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7-6
7.7
Constant
Tension
Adjustment
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7-8
7.8
ATL
Adjustments
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7-9
7.9
CHECKOUT AND ALIGNMENT
PROCEDURES
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7-9
7.10
Test
Equipment
Required
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. . 7-10
7.11
Preliminary
Procedures
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. 7-10
7.12
Playback Alignment
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7-10
7.13
Record Alignment
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. 7-12
7.14
Record Bias
Set
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. 7-12
7.15
Record Calibrate Alignment
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7-16
7.16
Record Equalization
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7-16
7.17
Erase
Alignment
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7-16
7.18
Depth
of
Erase
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7-16
7.19
Signal-to-Noise
Ratio
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7-16
7.20
Distortion
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7-16
7.21
Flutter
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. 7-17
SECTION 8. SCHEMATIC DIAGRAMS AND
PARTS
LIST
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8-1
8.1
GENERAL
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8-1