Radio controlled clock
With your radio controlled clock Sonoclock 755,
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 755 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 755 receives the DCF 77 transmitter free of charge via
the DCF 77 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 755 adjusts itself automatically from normal time to
summer time, and vice versa.
Super capacitor back-up system
The Sonoclock 755 is equipped with a built-in Super capacitor for the
back-up system which requires no battery. The time and alarm time
settings can be retained during temporary AC power failure by the Super
capacitor for a minimum of 4 hours. The LED display will be off and the
Clock and alarm will not operate during AC power failure. As soon as
the AC power is resumed, the built-in microprocessor will start to receive
the DCF time signals again and the clock will re-synchronize automatically.
Note: If the AC power is resumed after the super capacitor has been fully
discharged, the Sonoclock 755 will reset and the TIME and DATE will be
set again automatically by receiving the DCF time signal, but the ALARM
TIME will be reset to its default setting (you will need to set it again).
INTRODUCTION
10
GB
Reset button
• If, due to external interferences (caused by static charges of carpets, thunder-
storms, etc.), the control electronics of your Sonoclock 755 should receive
bad information signals, or if no entries at all are possible, press the RESET
button.
– For pushing this button, it is best to use a bent-up paper clip.
– This resets the unit to its initial state. The stored clock and alarm settings are
cleared.
Note: It is recommended to reset the unit when you connect it to the mains
power for the first time, as the Super capacitor may keep the previous
unexpected settings.
