Meinberg GPS165, Руководство пользователя

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5 GPS165 Features
5.4 Time code outputs
5.4.1 Introduction
The transmission of coded timing signals began to take on widespread importance in the early 1950´s. Espe-
cially the US missile and space programs were the forces behind the development of these time codes, which
were used for the correlation of data. The definition of time code formats was completely arbitrary and left to
the individual ideas of each design engineer. Hundreds of different time codes were formed, some of which were
standardized by the "Inter Range Instrumentation Group" (IRIG) in the early 60´s. Detailed information about
IRIG and other time codes can be found on
http://www.meinberg.de/english/info/irig.htm
Except these time codes other formats, like NASA36, XR3 or 2137, are still in use. The module however
generates IRIG-B or AFNOR NFS500 only.
Selection of the generated time code is done by using the monitor program.
5.4.2 Generated Time Codes
Besides the amplitude modulated sine wave signal, the board also provides unmodulated
DC-Level Shift TTL output in parallel. Thus six time codes are available.
a) B002: 100 pps, DCLS signal, no carrier
BCD time-of-year
b) B122: 100 pps, AM sine wave signal, 1 kHz carrier frequency
BCD time-of-year
c) B003: 100 pps, DCLS signal, no carrier
BCD time-of-year, SBS time-of-day
d) B123: 100 pps, AM sine wave signal, 1 kHz carrier frequency
BCD time-of-year, SBS time-of-day
e) B006: 100 pps, DCLS Signal, no carrier
BCD time-of-year, Year
f) B126: 100 pps, AM sine wave signal, 1 kHz carrier frequency
BCD time-of-year, Year
g) B007: 100 pps, DCLS Signal, no carrier
BCD time-of-year, Year, SBS time-of-day
h) B127: 100 pps, AM sine wave signal, 1 kHz carrier frequency
BCD time-of-year, Year, SBS time-of-day
i) AFNOR: Code according to NFS-87500, 100 pps, wave signal,
1kHz carrier frequency, BCD time-of-year, complete date,
SBS time-of-day, Signal level according to NFS-87500
j) IEEE1344: Code according to IEEE1344-1995, 100 pps, AM sine wave signal,
1kHz carrier frequency, BCD time-of-year, SBS time-of-day,
IEEE1344 extensions for date, timezone, daylight saving and
leap second in control functions (CF) segment.
(also see table ’Assignment of CF segment in IEEE1344 mode’)
k) C37.118 Like IEEE1344 - with turned sign bit for UTC-Offset
GPS165XHS Date: 5th November 2019 19