Xylem System 5000 User Manual - Manual (Page 54)

OUTPUTS
52
Synchronize
Though set to (None) by default, the System 5000
™
can be set to synchronize with the GOES time
due to the accuracy of the GPS system. A positive or negative Offset from the GOES time can also
be specified, if desired, to set a local time on the System 5000
™
.
GOES Self-Timed Options
Channel Number
Defines the Self-Timed Transmission channel number assigned by NOAA. The range for use with
the domestic satellites is 001 to 199 and represents a specific frequency for communicating with
the satellites. If the channel is an even number it is communicating with the western satellite. If
the channel number is odd it is communicating with the eastern satellite. Channels from 200 and
above are for international use.
Baud Rate
Defines the baud rate for Self-Timed transmissions. This may be different than the Random
transmission baud rate. Valid options are 100, 300 or 1200 baud. This will also be assigned by
NOAA.
Preamble
At the beginning of each transmission, a preamble signal is sent to the satellite. The preamble is
a carrier signal with no data modulation. This allows the satellite to lock on to the signal easier.
A short or long preamble is available, short being the default. Long preambles are only valid for
100 baud transmissions. On 300 and 1200 baud transmissions the preamble is always short. The
table below shows the time difference between the preambles.
Preamble Type Short Long
Total Preamble Time 0.98 seconds 7.3 seconds
Transmit Rate
Defines the interval at which data will be transmitted over the Self-Timed channel. The default
is a one hour rate (01:00:00). This along with the setting for the Transmit Time determine the
actual time that data will be transmitted. See the Transmit Time option below for an example. This
option also indirectly determines how much data will be sent each transmission. Use 00:00:00 for
a 24 hour transmit rate. The transmit rate is assigned by NOAA.
Transmit Time
This is a time offset for all timed transmissions based on the Transmit Rate.
This is also the time of the first transmission of the day relative to midnight. This offset time is
also assigned by NOAA and must be less than the Transmit Rate. This setting and the setting for