FORWARD:
In the past, measuring S video quality has been very difficult. Without some way to
measure actual video transmission results, there was no way to objectively evaluate system
performance, especially in terms of picture definition and the relative performance of the various
types of equipment available to implement S video transmission.
The term S Video is an abbreviation for Super Video, it is also referred to as Y/C video.
S video differs from normal composite video in several ways. The main difference is that the
Sync and Luminance (Y black and white) part of the signal is carried on one coaxial cable and
the Chrominance (C color) signal is carried on a separate cable. Usually these two cables are
combined into one cable with both coaxial cables inside the same jacket.
S video performs well with cable lengths under 25 feet, cable lengths longer than 25 feet
will have noticeable loss and should be measured and corrected with amplifier equalizers as
necessary.
DESCRIPTION:
The CM-1S is an adaptor that is used with the CM-1 CAMERA MASTER meter to
measure video levels on S video installations. The adaptor conveniently mounts on the two BNC
connectors on the top of the CM-1 CAMERA MASTER and is self terminating for both channels
of video information.
It can be used to verify the proper level of any S video system. Use this adaptor with a
CM-1 to measure any video level out of S video equipment to check and correct the levels in the
system. Use it to verify the proper operating level for any S video equipment.
The S female connector makes video connection simple. The unit has a built-in automatic
termination for both the Chrominance and the Luminance channels.
It can also be used to determine the location and measure the severity of low frequency
video loss, using the “SYNC” Position on the CM-1. Low frequency video loss can cause picture
darkness and rolling when the level is to low. If the level is to high it will cause “Blooming” over
brightness and loss of detail in the bright areas of the picture as well as “DIGITAL VIDEO
RECORDER OVERLOAD” a common malfunction.
The location and severity of high frequency loss can also be measured using the
“COLOR BURST” position on the CM-1. High frequency loss will result in the loss of picture
definition and can cause the video monitor to switch to black and white mode. If the video high
frequency level is too high it can cause color saturation and distortion of the video picture. This
can be seen as an extremely grainy picture with color flaring called “Commit Tails”. A Commit
Tail is an unnatural streak of bright color leading off to the right hand side of an oversaturated
color pixel.
CM-1Sisb
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