VooDoo DCR 6000, Планирование и монтаж: Руководство

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1. General DCR 6024/6128/6000
1 – 29 Planning and Installation – Rev. 1 / 7. 2001
Playback Amplifier
The playback signal provided by the playback head passes the low noise pre-am-
plifier BY 5002 having a balanced output to drive the rotary transformer with a de-
fined symmetrical impedance.After passing the rotary transformer, the play data
will be buffered in the playback buffer ( BM 5008). Its output signal is transferred via
a 50
Ω
HF cable to the playback equalizer.
The recording format is based on a digital segmented-field system with the helical
scan technology. That means that only segments of a field of 6 (24/25 Hz) or 5
(60 Hz) clusters of 8 tracks are recorded (see figure LEERER MERKER D-6 track
pattern).
With an uncoded bit length of 0.3 m a cluster of 8 tracks and a length of 150 mm
contains the data quantity of 4 Mbit.
300 clusters per second so produce a data quantity of 1.2 Giga bits/s.
The tape wrap angle 180
o
, so it is necessary that 8 of 16 record heads and 1 of 2
erase heads are located 180
o
opposite to each other and the same applies to the 8
of 16 play heads.
With one rotation of the headwheel two clusters with 8 tracks will be generated.
So the headwheel rotates with approx. 150 Hz or 9000 revolutions/min for the
300 clusters/s.
The play heads are positioned on the headwheel in a way that they not only serve to
playback data but also to monitor the data in record mode.
The record- and playback paths are physically and electrically separated to mini-
mize crosstalk.
In case of maintenance the Scanner Assembly should be exchanged by service
people only.
Segmented
fields
Scanner exchange