Sony D8MM-01, Training Manual

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12
Tape Speed
Since the drum speed was increased, there became a need to also in-
crease the tape speed. If the tape speed were not increased, 150 tracks
would have to be squeezed into the same area on the tape as 60 tracks.
The system could not function this way and use the same heads. Conse-
quently, the tape speed has been roughly doubled from 14.345 mm/sec
to 28.666 mm/sec. This allows digital 8 to have a track pitch (width) that
is close to that of analog 8. This allows for the use of the same heads for
analog playback and digital recording and playback.
A n a l o g 8 m m D i g i t a l 8
T r a c k I n f o r m a t i o n
A n a lo g D ig it a l
T r a c k s p e r f r a m e
2 5
T r a c k s p e r s e c o n d
6 0 1 5 0
D r u m r o t a t i o n s p e e d
1 8 0 0 r p m 4 5 0 0 r p m
T r a c k p i t c h ( w i d t h )
2 0 . 5 u m 1 6 . 3 4 u m
T a p e s p e e d 1 4 . 3 4 5 m m / s e c . 2 8 . 6 6 6 m m / s e c
R e c o r d i n g t i m e P 6 - 1 2 0 1 2 0 m in u t e s 6 0 m i n u t e s