Eurochron EFWS 301 Mode D'emploi page 51

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The weather station performs several reception attempts for the DCF signal
every day (at 2:00 a.m. and p.m. respectively). Therefore, just leave the weather
station standing for a day; maybe reception will be free of interference at another
time of the day.
A single successful reception per day will keep the deviation of the quartz clock
in the weather station below a second.
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