Panasonic AG-7510 - Page 5

As compared with the conventional VHS system, the
performance is remarkably improved as follows.
© Frequency shift: 3.8 MHz ~ 4.8 MHz to 5.4 MHz
~7MHz
© FMluminance bandwidth: Approx. 3.2 MHz to approx. 5.5
MHz
© Resolution: Approx. 240 lines to more than
400 lines
However, when the band is widened, the S/N becomes inferior
accordingly. To prevent this deterioration, in the S-VHS
system, the following measures are incorporated.
@ The sub-emphasis circuit is introduced in the preliminary
stage of the conventional main emphasis circuit.
© AnS-VHS tape made of newly developed magnetic material
is used exclusively for the S-VHS.
e
The
use
of
the
amorphous
heads
ensures
high
quality
pictures.
HD (high-dynamic) System
This unit records audio using the following two formats:
© Hi-Fi sound: An FM format employing a dedicated
rotary audio head permits high quality
sound recording and reproduction.
© Normal audio: This is the same format as that used ina
conventional video recorder.
<Compatibility with conventional recording methods>
This unit can record tapes in the conventional (normal) mode,
enabling tapes recorded on it to be reproduced on a
conventional machine.
The unit can also reproduce tapes recorded ona conventional
machine.
@ Independent dedicated audio head installed
on rotary cylinder
The audio of a video tape which was formerly recorded
using a fixed head is recorded on this unit using an audio
head mounted on a rotary cylinder. The video is recorded
over the audio using a dedicated video head. This
completely new format is called a high-dynamic system
(for creating superior sound quality).
Search head (R")
Dedicated rotary
audio head (L)
Video playback
head (L)
(Amorphous head)
Dedicated rotary
audio head (R)
Video playback
head (R)
(Amorphous head)
Search head (R’)
<Rear view>
@ Use of newly developed audio processing IC
A newly developed Hi-Fi sound IC processes the audio
input signals at the optimum level without deterioration.
As a result, the dynamic range has been increased from
the
conventional
value
of
80
dB
to
90
dB,
making
for
impressive dynamic sound.
© Incorporation of switching noise reduction
circuit
An electronic switching circuit and an active filter have
been incorporated in the noise reduction section which is
the
heart
of
the
audio
circuit.
Also
audio
capacitors
and
low-noise
resistors
are
used
in
the
level
sensor
section.
Asaresult, noise which is generated when the audio head
(Hi-Fi head) is switched has been greatly reduced, making
for highly linear, pure, clear Hi-Fi sound.
Audio Head Switched Timing
This unit Conventional system
<Switching noise>
Jog/Shuttle Search
@ Incorporates double DD ree! motor
The tape runs smoothly in the forward and reverse
directions, and the mechanism has good response.
@ Variable speed playback by microprocessor
control
By using the shuttle dial, the playback speed can be varied
according to the angle of rotation of the dial, and by using
the jog dial, the playback speed can be varied according to
the direction and speed of rotation of the dial. This is
useful for frame alignment when searching for the editing
points.