Meinberg LANTIME, Руководство по эксплуатации

Страница: 35 / 153

SETUP PZF PARAMETERS
In this submenu the PZF specific parameters can be edited. The distance to the
transmitter is entered in the menu "DISTANCE OF TRANSMITTER" for
compensating the propagation delay of the received pseudo-random code. This setting
should be done as exact as possible because the absolute precision of the time frame
is influenced by this value.
SETUP
PZF PARAMETERS
DISTANCE OF
TRANSMITTER
The basic model of the PZF509 includes a voltage controlled temperature
compensated oszillator (VCTCXO). Its nominal frequency of 10MHz is adjusted by
using two digital-to-analog converters (DACs). One of them is responsible for the
coarse tuning and the other one for the fine adjustment of the oscillator.
The value for the coarse-DAC is settable in the menu "OSCILL. AJUST" in the range
of 0 to 4095. If the edited value exceeds 4095 the maximum value is stored. This
menu only lets the user modify the coarse-DAC (CAL). The fine-DAC (FINE) is
displayed but not to edit. It can be cleared in the next menu.
SETUP
PZF PARAMETERS
OSCILLATOR
ADJUSTMENT
This value should only be changed by specialized personnel of company
Meinberg and not by the user!
Using the menu "CLR FINE DAC" the DAC is set to its mid-scale value and the
difference to its last value is added to the coarse DAC proportional.
SETUP
PZF PARAMETERS
CLEAR FINE
DAC
This process is released automatically if the value of the fine DAC exceeds its
limits (0...4095). Therefore the setting of the value to mid-scale by hand is
reserved for service purposes only!
The menu "TIME" lets the user edit the time of the PZF509 in hours, minutes,
seconds and set the daylight saving (MESZ) active or not. The LANTIME itself
always runs on UTC based time. This UTC-time is displayed on the LCD.
35