S
YSTEM
P
ARAMETERIZATION AND
O
PERATION
6842 GPS Slim Line System - V09.01
43 / 98
hopf
Elektronik GmbH
Nottebohmstr. 41 • D-58511 Lüdenscheid • Tel.: +49 (0)2351 9386-86 • Fax: +49 (0)2351 9386-93 • Internet: http://www.hopf.com • E-Mail: [email protected]
4.1.4.2 Delayed DCF77 Simulation and DCF77 Pulse Switch-off
The System 6842 simulates the DCF77 antenna signal (DCF77 Antenna Simulation) and the
DCF77 Pulse Signal (on the System Bus) for the synchronization of other
hopf
systems or
external systems.
These signals do not contain synchronization status information for the transmitting device
(Master). For this reason, connected equipment is always radio-synchronous with this signal;
even when the transmitting device is running on its own internal quartz base.
In order to identify a possible Master System synchronization problem in the Slave System,
DCF77 Antenna Simulation and DCF77 pulse output can be switched off by means of a
timer.
After switch-off, a 2Hz pulse signal is transmitted instead of the time information.
Synchronization of the connected system is no longer possible when the signal is modulated
in this way.
There are two settings, each with a different effect:
2 to 254 Minutes Setting
The System must be synchronized by GPS at least once before beginning to simulate the
signal. DCF77 Antenna Simulation output also occurs again following DCF77
synchronization failure, for the set time span. After this time has lapsed, no valid DCF77
signal is then transmitted in the event of ongoing reception faults. The connected devices are
no longer synchronized and may trigger an error message as a result.
255 Minutes Setting
Simulation always takes place on this setting (independent of synchronization status).
By this means, DCF77 simulation can be produced for any other time entered via the
keypad. This setting is mainly used to test time-dependent functions in the connected
equipment. In this case please note that the antenna cable should be disconnected from the
equipment, since synchronization via the antenna overwrites the time entered manually.
Modulation of the DCF77 pulse (1Hz) only begins after the second minute
change following the entry of a time, or 2 minutes after equipment switch-
on, if correct back-up clock information is available.
Viewing and changing the value takes place on the same selection screen with the following
command:
Selection frame:
T I M E - O U T F O R D C F
S I M U L A T I O N Y / N _
Display frame:
D C F - S I M S T O P
A F T E R >
0 5 5
< M I N
STANDARD Value: 055
The time is increased with the
+
key and reduced with
-
.
On exiting the program via the
BREAK
key the last displayed value is stored in a failsafe
manner.
