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Overview USB5131
The radio remote clock USB5131 has been designed for communication via the serial
USB interface. The required power is provided via the USB cable as well, so there is no
need for any external power supply.
The DCF77 signal received by the internal antenna is passed to the on-board LF
receiver where it is demodulated by a synchronous detector with automatic gain control.
The demodulated time marks from the receiver circuit are filtered and decoded by the
microprocessor. If no errors are detected in the current time message an additional
plausibility check against the previous time message is performed. If that plausibility
check passes, too, the real time clock on the board is adjusted corresponding to the
decoded time and date.
The USB5131 module provides two integrated LEDs, which show the demodulated
time marks (MOD LED) and the state of synchronisation (FR LED).
The scope of supply includes an USB cable with 3 mtrs. of length to connect the
USB5131 directly to a PC’s USB port.
Also included is the driver software for Windows 2000/XP/VISTA
®
operating sys-
tems that is used to set the system time of the computer and shows some important status
information of the USB5131.
Driver software for other operating systems can be found on the Meinberg homepage
for download: http://www.meinberg.de/english/sw/index.htm
Front View USB5131
