When
we talking about S-VHS cable, we need to know the S-VHS, so what S-VHS is? I would
like to give you a general account of S-VHS below:


S-VHS
is short for super video home system; this is a new model developed by
JVCKENWOOD Corporation (Abbreviation: JVC) in succeeding of VHS by other
companies, the new model have a characteristic of high resolution, high
fidelity, 20Hz-20KHz’bandwidth, 90dB above dynamic and signal-to-noise ratio. On
a par with LD’s image and CD’S sound, S-VHS becomes indispensable equipment for
all the Hi-Vi Lovers.
S-VHS
have an inferior image quality than DVD’s, but 500TVL’s resolution for most TV
can’t achieve, and also you can hardly judge the image quality difference with
our naked eye either it played in S-VHS or DVD. Furthermore, the forward compatibility
means all VHS tapes can be played in S-VHS player, but it’s not the other way
around.
Developed
on the basis of VHS, S-VHS greatly improved the performance for the
compatibility with VHS, and below ,I need to lay the details concerning the electronic
circuit, magnetic heads, tapes which have
a thoroughly improvement.
1,The
video’s Y signal for S-VHS
expanded upwardly to the phase of 7MHz, frequency deviation improved to 1.6MHZ,effective
bandwidth for brightness improved to 5MHz comparing with VHS’s 1.0MHz and 3.2MHz.According
a general calculation for resolution that 1MHz’s
bandwidth equals 80TVL, we can know that VHS’s
resolution is about 250TVL,S-VHS reached to 400TVL above. That’s huge
improvement for image quality.
2,
after the improvement of bandwidth, the crystalline magnetic head is no long
adapt to eddy current loss and the clutter interference by high frequency, so
JVC redeveloped amorphous magnetic heads which was laminated by several
thin-films to improve insulation and reduce eddy current. Quite effectively
improved high–low frequency performance,
and bettered the chroma frequency signal in the lower end of the spectrum,
which greatly improved the color saturation.
3,
In order to reduce interference between brightness (Y) signal and color (C)
signal, S-VHS video recorder handling Y/C signal separately on recording and playing,
placing the Y and C signal in a better functioning condition.
4,To
adapt the needs of high sensitivity of new magnetic head of broadband, using chromium
and Iron oxide Fe2O3 for high magnetic saturated coating
with a thickness of only 0.5μm ,greatly improved thermoremanent
magnetization(TRM)and coercive force, in
this way, the signal recording improved.
5,
during the process of signal transaction, time-constant is utilized to limit amplitude
and impose accentuation, which, in a way, greatly reduced the edge noise of
image. The noise in the nonlinear region is also repressed by synchronizing time-constant
with inputted signal level.
6,With
an audio frequency response of 12 KHz, it’s
not enough for VHS recording a high fidelity program. 33.35mm/s’ tape speed,
relatively lower than cassette tape’s
47.6mm/s; Improving the tape speed is the only way to improve frequency
response. Introducing the specialized Hi-Fi sound accompaniment magnetic head
in the high speed rotary drum can make magnetic head’s relative tape speed running 5.8m/s,
which is 170 times higher than static sound accompaniment magnetic head, can achieve
20KHz’ frequency response recorded by rotary magnetic head, if the recording in
EP Mode(1/3’s normal speed-slow
speed), still a record of 20KHz maintained ,which makes high fidelity sound
accompaniment come true.
7,
Based on different characteristics of S-VHS sound accompaniment frequency
modulation and whiteness’s frequency modulation. Deep oriented recording method
adopted to record the accompaniment sound signal in a blank tape before
recording the image signal on the surface, improved the accompaniment standard
and efficiently used the tape.
Now,
let’s come back to S-VHS cable, while running S-VHS machines properly, a cable
connecting between devices is necessary. A brief and simple definition for
S-VHS cable is a kind of wire connecting S-VHS devices. Anyway, you can easily
know S-VHS cable after you know what S-VHS is. Good quality cables can guarantee
S-VHS’s sound and image quality; make S-VHS’s advantage prominent. So don’t lose
your S-VHS’s advantage by choosing a good quality cable can be never ignored
while you buy the machine but the cable separately.
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