evertz 5010, Инструкция по эксплуатации

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Model 5010 Time Code Master Manual
OVERVIEW
Revision 3.1.1
Page 1-5
In the
continuous jam sync mode
, the generator and reader times are compared
with each other during each frame, automatically compensating for the decoding
offsets. If for any reason they are not equal, the jam is bypassed, and the generator
substitutes the next frame number. If the number of consecutive jam bypass errors
exceeds 5, the last valid reader time is jammed into the generator again. In the
absence of valid reader data within the last 5 frames, the generator continues to
increment normally until valid reader code resumes. At this time it will be re-jammed
to the reader, thus repairing large dropouts on the reader tape. The generator can
also be configured to stop when there is no incoming code. The continuous Jam
sync mode is selected by pressing the SHIFT + JAM keys, and is indicated when the
JAM LED is On.
In the
momentary jam sync mode
, the reader time is 'jammed' into the generator
for one frame only. The generator continues to increment normally from that point
on, without regard to the reader frame numbers. The momentary jam sync mode is
selected by pressing the JAM key.
USER BIT TRANSFER:
In some applications it may be desirable to transfer the user bit data from
the reader tape, and generate new time information. In other applications, both the
time and user bit information should be transferred. Both of these options are
available in addition to the normal jam sync and non jam sync modes.
JULIAN DATE:
The Julian day number is a count of days elapsed since Greenwich mean noon on
January 1, 4713B.C. January 1st, 1993, was JD 2448989; January 1st, 2000 will be
JD 2451545.
MODIFIED JULIAN DATE (MJD):
The Modified Julian Date is a continuous count of the number of
days elapsed since 17 November 1858. It is often more useful than conventional
calendar dates for record keeping over long periods of time, since the MJD's of two
events can easily be subtracted to determine the time difference in days. Usually, the
MJD is specified as a number with 5 significant digits. As an example, the MJD for 1
January 1995 is 49718, meaning that this many days have elapsed between 17
November 1858 and 1 January 1995. The Modified Julian date is calculated by
subtracting 2400000.5 days from the Julian Date. Thus the Modified Julian Day 1
begins at Greenwich midnight.
UNIVERSAL COORDINATED TIME
UNIVERSAL TIME, COORDINATED (UTC):
Universal Coordinated Time (UTC) is an international time
standard that defines a time that doesn't depend on where we are on Earth.
Universal Time (UTC), Greenwich Mean Time (GMT), and Zulu Time (Z), are based
at the prime meridian (0° longitude) of Earth and are used to avoid confusion of time
zones.
STANDARD TIME:
The civil time adopted for a country or region.
DAYLIGHT SAVING TIME:
The civil time observed when daylight saving time is adopted in a country
or region. It is usually standard time + 1 hour.