Radio controlled clock
With your built-in radio controlled clock, you are in the possesion of an absolutely precise alarm- and
appointment clock which sets itself fully automatically to the radio-transmitted time signal of the most
accurate clock in the world: the atomic clock of the Bundesanstalt (Federal Standards Institute) in
Braunschweig/Germany (PTB). The time deviation is smaller than 1 second in 1 million years.
Your radio controlled alarm clock SONOCLOCK 910 receives time 'telegrams' on the longwave band (77.5
kHz) from the official German standard frequency and time signal transmitter DCF 77, located in
Mainflingen (24 km south-east of Frankfurt/Main). This transmitter has a range of up to 1500 km.
Your SONOCLOCK 910 receives the DCF77 transmitter free of charge via the DCF77 antenna in any place
where reasonable longwave reception is possible with a good portable radio. In many cases, your alarm
clock receives the time telegrams at a considerably greater distance from the transmitter, but here the local
reception conditions play an important role.
The built-in microprocessor of your alarm clock processes the received time telegrams and controls the
clock fully automatically. As soon as reception of the DCF time signals is possible again after an
interruption, the clock will immediately be synchronized. In addition to the advantages of time precision and
a wake-up signal accurate to the second, the radio controlled SONOCLOCK 910 adjusts itself automatically
from normal time to summer time, and vice versa.
General
Positioning the set
Caution should be exercised if the set is placed on furniture as surfaces are often coated with lacquers and
plastic finishes containing additives which attack the material of which the feet of the set are made, leaving
stains which can only be removed with difficulty or not at all.
Preparations for use
The unit is designed to operate from a mains supply of 230 - 240 V, 50/60 Hz.
The unit is only fully isolated from the mains if the mains plug is removed from the wall socket.
• Connect the aerial supplied to the ANT socket at the back of the set.
– This aerial is used for FM radio reception and reception of time telegrams..
SC 910 page 11
Radio controlled clock
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GB
