Meinberg RU226 Manuel d'utilisateur télécharger pdf

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RU226

DCF77-receiver

General information about DCF77

The Meinberg receiver module RU226 receives the signal of the long wave transmitter DCF77.

This long wave transmitter installed in Mainflingen near Frankfurt/Germany transmits the refe-

rence time of the Federal Republic of Germany. This time reference is either the Central European

Time (MEZ) or the Central European Summer Time (MESZ).

The transmitter is controlled by the atomic clock plant at the Federal Physical Technical

Institute (PTB) in Braunschweig/Germany and transmits the current time of day, date of month

and day of week in coded second pulses. The complete time information is available once every

minute.

At the beginning of every second the amplitude of the high precision 77.5kHz carrier frequency

is shifted to 25% for a period of 0.1 or 0.2 sec. The length of these time marks represents a binary

coding scheme using the long time mark for logical ones and the short one for logical zeroes. The

information about the current date and time as well as some parity and status bits can be decoded

from the time marks of the 15th to the 58th second every minute. The absence of any time mark at

the 59th second of a minute indicates the beginning of a new minute with the next time mark.

Switching to MESZ or MEZ can be done automatically. The reception of the time information

is free of charge and does not need to be registered.

Figure : decoding scheme

M Start of minute (0.1 sec)

R RF transmission via secondary atenna

A1 Announcement of a change in daylight saving

Z1, Z2 Time zone identification

A2 Announcement of a leap second

S Start of time code information

P1, P2, P3 Parity bits

General information RU226

The module RU226 is mounted in a plastic case and contains the ferrite antenna and the comlete

straight receiver. Two LEDs are included for visualization of the demodulated time marks and the

field intensity of the DCF-signal. The case is delivered with a stick pad for easy mounting (e.g. on

windows/furniture). As an output-signal, the demodulated time marks are available at a four-wire

cable.

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Résumé du contenu

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FUNKUHRENRU226DCF77-receiverGeneral information about DCF77The Meinberg receiver module RU226 receives the signal of the long wave transmitter DCF77.T

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FUNKUHRENRU226DCF77-receiverAntennaGenerally, the exact mounting of the antenna is important. It has to be placed in longitudinaldirection to the tran

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FUNKUHRENRU226DCF77-receiverOutput signalFor evaluating of the DCF-time-telegramm, the module delivers the demodulated time marks.The following values

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FUNKUHRENRU226DCF77-receiverConnection of an optocouplerThe signal level of the DCF_MARK-output isn't sufficient for some applications. In that c