Meinberg LANTIME, Руководство по эксплуатации

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PZF Menu items
The type of DCF-clock and the software revision are displayed first after power-up.
The following information are readable before the PZF509 switches to time-display
automatically:
PZF REC.
REV:x.xx
The handling of any queries will be simplified if the software revision is given by the
user.
The following menus are available then:
TIME: The current time is displayed.
DATE: The actual date appears on the display.
DAY o.W.: The day of week will be displayed.
PZF STAT: Information about the decoding of the pseudo-random sequence are
available in this menu. The following texts may be displayed:
GSYNC: The pseudo-random sequence is read into the internal RAM for one
second and the system tries to achieve a coarse synchronisation.
This procedure starts after power-up or worse reception for more
than ten seconds.
K: xx%: If the coarse synchronisation was successful, the receiver enters the
state of fine-correlation. The system tries to lock the received PZF
as exact as possible to generate a precise time frame. The display
shows the correlation coefficient at the end of each second, which
can be in the range of 52 % to 77 %. A high value for the coefficient
should be achieved by choosing a suitable position for the antenna.
The essential part of the tracking is completed five seconds after the appearance of
'K:xx%' and the generation of pulses per minute and per second starts. Tracking steps
of three microseconds are possible each second until the internal real time clock is
synchronized (two minutes max.). Afterwards, corrections of the time frame are
executed per minute only. The direction of these steps is displayed by the characters
'>' or '<' behind the digits of the correlation coefficient.
FIELD: The digitised value of the field strength is displayed in this menu.
There is a logarithmic relation between this value and the field
strength. This menu is useful for mounting the antenna, like
described in chapter 'Assembly of antenna.
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