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Battery wai
Cassette warning
Sports mode frame
d Manual
a Central emphasis AF
rning
a Battery voltage decrease
Blinking
a Recording not possible
b No cassette
c System error detection
a Dew condition
Blinking
Blinking
Fast blinking
Display Position/Contents
Diisplay Character in VF
Mode
a REC
REC
Lit
REC mode
b PAUSE
PAUSE
Blinking
PAUSE mode
;
c STOP
STOP
Lit
STOP mode (only VTR)
Onereten neces
d PALY
PLAY
Lit
PLAY mode
e FF
FF
Lit
FF mode
f REW
REW
Lit
REW mode
aSP
SP
;
Tape speed
BLP
Lp
All modes
Counter
a Linear time counter
M-1:15:37
Lit
All modes
a Sports
Prasat nodal
b Auto high-speed shutter
c Close up
Lit
CAMERA PW ON E-E
Operation mode
:
d Low light
f REC
REC
Lit
Mode display
g PAUSE
PAUSE
Blinking
CAMERA PW ON E-E
a Automatic
AF
Auto-focus
Cees
ea
Lit
CAMERA PW ON E-E
c Manual
MF+
CAMERA PW ON E-E
During voltage decrease
detection
Warnin:
'
+
ng ad
b Tape remainder below 5 min.
{| TAPE
Blinking
REC mode
ape end,
dew)
eg
)
¢ Tape end
TAPE END
.
Itage dr
cause wolage
drop
> IlxBATT
Adjustment mode
adjustment
Time display
b Time
14:25:48
CAMERA PW ON £-E
Date display
a Date
21.10.1992
CAMERA PW ON E-E
|
During
system error
Error code
a Error code
E04
Lit
g .
detection
Table 6-10.
Display specifications
6-19
i
a
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4
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;
2.
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ny
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ao
Sas
icin ace
7. SERVO SYSTEM
7-1.
OUTLINE
In the VTR, rotation of the drum motor and capstan motor
is controlled by the servo circult.
« In the
recording
mode,
the video
signals
must
be
recorded on the tape at the proper pitch.
The drum servo controls rotation of the drum motor so
that the rotational phase of the drum motor is always
synchronized with the phase of the video signal to be
recorded.
Thus the vertical sync signal of the video
signal is recorded on the specified tape position.
The rotation of the capstan motor is controlled for a
constant
speed.
Therefore
the tape
speed
become
constant and the signals are recorded on tape at the
proper pitch.
.
In the playback mode, the servo control the both motors
to obtain the maximum
playback signal with no time
base fluctuations.
The
rotation
of the drum
motor
is controlled for a
constant speed,
In 8mm video, a system called ATF is adopted so as to
control the rotation of the capstan motor for optimum
tracking over the recorded tracks.
Rotation sensor
Drum System
7-2.
CONFIGURATION
The overall block diagram for the servo system is shown in
Fig. 7-1.
The
servo
system
can
basically
be
divided
into the
following blocks:
a) Rotation Detection Element and Amplifier
The motor is equipped with a detection
element for
rotation detection. The very low level signal obtained
from the element is amplified to a logic level by the
amplifier, and input to the servo processing circuit.
b) Servo signal processor block
This block detects the rotational speed and phase of the
motor based on the sensor signal and processes the
resulting
detection
signal. The
signal processing
is
performed by the microprocessor.
c) Power amplifier, motor driver and motor
The contro! signal is converted into a power signal for
driving the motor.
d) ATF signal processor block
.
in order to get optimum tracking, in 8mm video, a signal
called pilot signal is recorded on tape in the recording
mode and the ATF error signal corresponding to the
shift amount
of the tape running Is detected
by the
recorded pilot signal in the playback mode.
The circuit is configured almost entirely from ICs. The ICs,
etc., which comprise the various blocks are shown in Table
7-1,
Capstan System
Print coil type sensor (PG/FG)
MR sensor
Sensor amplifier
BA14741F
Bilt-in Mechanism
ATF detection
---
LV4050W
Speed/phase detection
sie shee ts scassii
Car sore)
Motor driver
CXA8008MQ
Bilt-in Mechanism
Motor
Three-phase bi-directional
sensorless motor
Hall element detection type
brushless motor
Table. 7-1.
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