La Crosse Technology WT-3181pl User Manual

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RADIO CONTROLLED ANALOG CLOCK

INSTRUCTION MANUAL

Quick set up instructions

Welcome to the world of atomic 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

• Twist and lift open the battery compartment cover at the back of the clock
and insert 1 fresh AA, LR6 1.5 volt ALKALINE battery according to the
polarity marked on the case.

• Once the battery is installed, the clock will begin 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 (for the default Pacific Time Zone), 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 every two hours 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.

• Press time zone button to select a time zone after the clock received the
WWVB signal. If you are in the Pacific Time Zone- you are ready to hang
your clock.
If you are not in the Pacific Time Zone, select your time zone by pressing
one of the four time zone buttons PT-Pacific Time, MT-Mountain Time, CT­Central Time, ET-Eastern Time. 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. If you live in an area that does not recognize
DST (Arizona and Indiana) you must press the (unmarked) DST button for
one second to deactivate your clock’s DST program.
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. (See
instructions below).

• Replace the battery compartment cover.

THAT’S IT! During the night your clock will automatically set itself.

BATTER

COMPARTMENT

.

BATTERY COMPARTMENT
COVER

MANUAL TIME SET

BUTTON

PACIFIC TIME

MOUNTAIN TIM E

CENTRAL TIME

BATTERY
COMPARTMENT

EASTERN TIME

DST ON/OFF BUTTON

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 atomic 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 atomic clocks always
keep precise time. The changeover from standard time to daylight saving 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.

Once the battery is installed the clock will begin 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 even
numbered hour until a signal is received. If the time is manually set the clock will

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continue to periodically search for a signal and automatically reset the hands

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when the signal is received.

The La Crosse Technology atomic clock is designed for indoor or outdoor

use. For indoor locations, 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 provide the best signal. For outdoor locations, try to select a
location sheltered from direct sunlight and rain, preferably under a roof or porch
area, and facing Colorado for better reception of the WWVB signal.

Note:

• Do not submerge clock in water.

• Extreme temperatures, vibration, and shock should be avoided to prevent

damage to the clock.

The WWVB time signal will easily penetrate masonry and wood framed

buildings. The WWVB signal will penetrate almost every residential building and
most steel buildings if they have adequate windows. It is not possible, however,
for the WWVB signal 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 receives the WWVB signal it will automatically set the hands to the exact
time.

La Crosse Technology atomic 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 atomic clocks can
be manually set and used anywhere.

For more information on the NIST and radio controlled time, see
www.boulder.nist.gov/timefreq/

SET THE TIME USING THE MANUAL TIME SET BUTTON

In some cases, the La Crosse Technology atomic clock may not receive the
WWVB signal due to atmospheric disturbances or hard to reach locations such as
inside shopping malls. In this case, please use the Manual Time Set button,
located at the back of the clock to manually set the time. To do this:

MANUAL TIME

SET

1. Press and hold the Manual Set button.

2. Release the Manual Set button and again press and hold the Manual Set

button. The minute and hour hands will fast-forward while the button is held.

3. Keep holding the Manual Set button until the time is set as required.

4. Release the button. About 3 seconds later, the second hands will start to

move and the clock is now running with manual time.

Note:

When the clock displays manual time, it will continue to try to receive the WWVB
signal at each of the even numbered hours: 0:00, 2:00, 4:00, 6:00 … 20:00 &
22:00.

TEMPERATURE AND HUMIDITY

The La Crosse Technology atomic clock has two analog sensors that measure
surrounding temperature and humidity. The temperature information is displayed
in degrees Fahrenheit and Celsius, and humidity data is displayed in percentage.

The thermometer and hygrometer have been calibrated in factory. To check the
sensors accuracy, tune to your local weather forecast information broadcast for
the latest weather information. It may be necessary to adjust the sensors.

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To manually adjust the sensors, gently turn the corresponding knobs located at
the back of the clock until required data has been reached.

Calibration
knob for
thermometer

Humidit

display in %

Calibration knob for
hygrometer

Outer ring displays
temperature in
degree Fahrenheit

Inner ring
displays
temperature in
degree Celsius

TROUBLESHOOTING

The wonderful advantage of owning a La Crosse Technology atomic 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 atomic clock must have a fresh battery to

receive and process the time signal.

Location - Try a different location, ide ally near a window. It should be at least six

feet from computers, TVs, air conditioners, other atomic clocks and
other electrical appliances that cause interference.

Weather - Electrical storms between you and Colorado during the night will

interfere with the WWVB signal.

Reception - The clock seems to “take off” for no reason and then stopping

at the same time.

It is not uncommon for the clock to make a "correction", sometimes
daily. This happens if the clock gets ahead of itself by a fraction of
a second. To correct this the clock will advance a complete rotation
the next time it receives a signal.

DAYLIGHT SAVING 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

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 atomic clock be used outdoors?
A. Yes, but only in a dry environment and in a temperature range between -10 °F

and 131 °F. The clock is NOT water-resistant.

Q. Can the La Crosse Technology atomic clock be wired to control timing circuits?
A. No.

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