Radio Controlled Analog Clock
Quick set up instructions
Welcome to the world of radio controlled timekeeping technology. We hope you will enjoy the
convenience of never having to set your clock again and the confidence of knowing exactly what time it
is.
• Insert 1 fresh AA, LR6 1.5 volt ALKALINE battery
• Press button to select a time zone. THAT’S IT! During the night your clock will
automatically set itself.
For a better understanding of how and why your clock works please continue reading.
Nothing is more precisely measured than time!
And nothing keeps track of time more precisely and trouble free than La Crosse Technology radio controlled
clocks.
Since the beginning of time, man has been fascinated with the measurement of time and has devised more
accurate machines to trap and measure time. Today, time is precisely measured in the United States by the most
accurate clock in North America, the Atomic Clock of the US National Institute of Standards and Technology,
Time and Frequency Division in Boulder, Colorado. A team of atomic physicists continually measures every
second of every day to an accuracy of ten billionths of a second per day. These physicists have created an
international standard, measuring a second as 9,192,631,770 vibrations of a Cesium 133 atom in a vacuum. This
atomic clock regulates the WWVB radio transmitter located in Fort Collins, Colorado, where the exact time signal
is continuously broadcast throughout the United States at 60 kHz to take advantage of stable long wave radio
paths found in that frequency range. Radio waves at these low frequencies use the earth and the ionosphere as a
wave-guide and follow the curvature of the earth for long distances.
The built in antenna system will receive the WWVB signal anywhere in North America within 2000 miles of
Fort Collins where long-wave radio reception is undisturbed. A microprocessor activates the receiver and
processes the time signal from Fort Collins overnight.
Through the radio signals, La Crosse Technology radio controlled clocks always keep precise time. The
changeover from standard time to daylight savings time, and vice versa, takes place automatically with the same
precision.
Additional details
To set up your clock simply install one fresh AA, LR6 ALKALINE battery. Due to the nature of long wave radio
signals it is normally not possible to receive a signal during the day so it is best to install the battery late in the
evening. Select your time zone by pressing one of the four time zone buttons PT-Pacific Time, MT-Mountain
Time, CT-Central Time, ET-Eastern Time. The time zone buttons may be pressed any time after installing the
batteries. If multiple buttons are pressed the clock will set to the time zone selected last. If no time zone is
selected the clock will default to Pacific Time. Another time zone can be selected during or after the clock has set
itself. Your clock can only set itself to one of the four time zones stated above. For time zones outside of PT,
MT, CT or ET you must manually set the time using the Manual Time set button on the back of the movement.
When the battery is installed the second hand will advance eight seconds (two seconds per step x four
steps). The clock is now searching for a signal. For the initial setting it is recommended to stand the clock in an
upright position near a window. Within five minutes the clock will either receive the WWVB signal and set itself to
the exact time, or it will determine that the signal is not receivable at its current location and time of day. If a
signal is not receivable it will fast-forward the hands to the 4, 8, or 12 o’clock position and search for WWVB each
hour until a signal is received. If the time is manually set the clock will continue to periodically search for a signal
and automatically reset the hands when the signal is received.
Select a location to place your radio controlled clock where it will be at least six feet away from a TV,
computer, air conditioner or other household electrical appliances. The optimal location is near a window.
Windows facing Colorado providing the best signal. The WWVB time signal will easily penetrate Masonry and
wood framed buildings. WWVB will penetrate almost every residential building and most steel buildings if they
have adequate windows. It is not possible, however, for WWVB to penetrate most indoor shopping malls and
rooms in the center of large office buildings that do not have windows. In buildings that WWVB cannot penetrate
you may set the time using the manual time set button. When the clock is exposed to the WWVB signal it will
automatically set the hands to the exact time.
La Crosse Technology clocks do not receive or process radio controlled time signals from Germany’s DCF
77, Japan’s J Ga AS, or England’s MSFs atomically regulated transmitters. La Crosse Technology clocks can be
manually set and used anywhere.
For more information on the NIST and radio controlled time, see www.boulder.nist.gov/timefreq/
Troubleshooting
The wonderful advantage of owning a La Crosse Technology radio controlled clock is that it is virtually trouble
free. If the clock receives a clear signal it will set itself perfectly. If it does not receive a signal consider the
following:
Battery - The La Crosse Technology clock must have a fresh battery to receive and process the time signal.
Location - Try a different location, ideally near a window. It should be at least six feet from computers, TVs, air
conditioners, other Radio-Controlled clocks and other electrical appliances that cause interference.
Weather - Electrical storms between you and Colorado during the night will interfere with the WWVB signal.
Although we cannot control the weather we can help you predict it (see www.lacrossetechnology.com).
Daylight Savings Time
The National Institute of Standards and Technology and WWVB encode a special DST “bit” in the WWVB
transmission for DST. Your La Crosse Technology clock will read this information and automatically advance the
hands one hour in the spring and eleven hours in the fall.
Arizona and Indiana
If you live in an area that does not recognize DST you must press the (unmarked) DST button for one second to
deactivate your clock’s DST program. To reactivate the DST program simply press the DST button again for one
second.
Frequently Asked Questions
Q. How long will the battery last?
A. A good AA alkaline battery will last over one year. If your clock is located in an area with little interference
where it can quickly receive a signal the battery can last much longer than one year.
Q. Can a La Crosse Technology clock be used outdoors?
A. Yes, but only in a dry environment and in a temperature range between 41 F and 131 F. The clock is NOT
water-resistant.
Q. Can the La Crosse Technology clock be wired to control timing circuits?
A. No.
Q. Why does the second hand move only once every two seconds?
A. When the battery drops below 1.25 volts the clock indicates that it is time to change the battery by advancing
the second hand in two second steps. The operating voltage range is 1.25 to 1.75 volts.