S T A R T Frame - Kenwood DP-1100 B Service Manual

1-6 F R A M E S Y N C H R O N I Z A T I O N A N D F R A M E
S T R U C T U R E
R e p r o d u c t i o n signals c a n n o t be r e c o v e r e d RF signals d o n o t
c o m e o u t for a l o n g t i m e due t o d r o p o u t or o n e i n f o r m a t i o n bit
has b e e n shifted o w i n g t o jittering in digital r e c o r d i n g or
p l a y b a c k . Because o n e bit shift of a digital signal m a k e s t h e
signal quite different in its signal level.
T h e r e f o r e , by d i v i d i n g a r e c o r d e d signal t o m a n y small blockjs,
t h e s y s t e m is o r g a n i z e d so t h a t even w h e n a signal is d i s t u r b ­
ed d u e t o jittering or t h e like, a bit s y n c h r o n i z a t i o n is a l w a y s
estabilished at the n e w block t o identify t h e j o i n t part b e t w e e n
b l o c k s . S u c h a block is called a " F r a m e " . Frame Sync signals
are inserted t o indicate the b o u n d a r y of the f r a m e a n d t o
m a k e a bit s y n c h r o n i z a t i o n . Fig. 1.9 s h o w s the structure of
o n e f r a m e .
F r a m e S t r u c t u r e
• Margin Bit
User's Bit
Data Bits
I
2 3 4 5 6 7
14 14 14 14 14 14 14 14 14
: : : . ;
-3
3 A
Data Symbol 1 (14 Channel Bits)
Control Display Symbol (14 Channel Bits) PQ Data Absolute Music
Sync Pattern (24 Channel Bits)
11 Channel Bits
2 x Tmax

S T A R T FRAME

II. FUNDAMENTALS
1-frame (588 Channel Bits)
Parity
8 9 10 11 12 13 14 15 16 17
14
14 14 14 14 14 14 14
: : : : . 2
2
i
11
Fig. 1.9
Channel bits
Frame Synchro­
nization
Users buts
Data bits 14 b i t x 2 4 = 336
Error correction
14 b i t x 8 = 1 1 2
bits (Parity bits)
486
Data Bits
18 19 2 0 21 2 2 2 3 2 4 2 5 2 6
14 14 14 14 14 14 14 14 14
: :
i
Channel Bit Frequency = 4 . 3 MHz
Frame Frequency = 7 . 3 5 kHz
D P - 1 1 0 0 B II
Margin bits Total bits
24
3
14
3
3
b i t x 8 = 24 = 72 408
3 bit x 24
136
102 588
Parity
2 7 2 8 2 9 3 0 31 32
14 14 14 2 4
14 14
:
; :
i :
27
17