WT-5432 La Crosse Technology Atomic Projection Alarm Clock

Every night, the WT-5432 La Crosse Technology Atomic Projection Alarm Clock calibrates itself to the world's most accurate clock by receiving WWVB radio transmissions. These transmissions contain time information from the U.S. atomic clock source, operated by the U.S. Commerce Department near Boulder, Colorado. The built-in antenna ensures reliable signal reception up to 2000 miles (3200km) from the WWVB transmitter.

The WT-5432 is titanium in color, and features gracefully rounded styling accents. Its LCD display shows time of day, date, time zone, indoor and outdoor temperature (selectable), and a weather-forecast icon with tendency arrow. The clock's weather-forecasting feature senses barometric pressure over time and adjusts the indicator icons and tendency arrows to provide accurate forecasts for the next 12 to 24 hours based on pressure trends.

The time and outdoor temperature are projected, although not simultaneously, on the wall or ceiling. This clock has dual alarm settings with adjustable snooze. A TX6U remote transmitter for outdoor temperature reporting is included with the clock. Designed for table or shelf placement, the clock can be powered from the included ac adapter or optionally from three AA batteries.

Features:

Accurate to 1 second per million years
Sets automatically to WWVB radio signal (manual setting is also possible)
12/24 hour time display (hour, minute, second)
Calendar display (day, month, date)
Three projection modes: time only, outdoor temperature only, or alternating between the two
Projection is continuous with ac powering
Projection is initiated via pushbutton and 3 seconds in duration with battery powering (pushbutton projection is also available with ac powering)
Projection auto-focusing for display from 3 to 6 feet away; maximum projection distance is 6 feet (2 meters)
Projected display can be rotated 360° in 90° increments for proper viewing
Projector case rotates 180° to further orient the projected display
Three different intensity settings for projected display, plus an "off" setting. With battery powering, "off" is the only option; the intensity is not adjustable and the projection is via pushbutton (not continuous).
Dual alarm settings with adjustable snooze function
Time zone setting (13 available) with map display for U.S. time zones
Daylight saving time ON/OFF option
Indoor temperature display in either °F or °C
Outdoor temperature display (via 433 MHz transmission) in either °F or °C
Three weather-forecast icons (sunny, partly cloudy, and rainy) with tendency arrows
Electro-luminescent backlight for LCD display (2-second duration)
Integral base for table/shelf/desktop placement
Clock powered by ac adapter (included) or by three AA 1.5V alkaline batteries (not included), with normal life of about 1 year
Remote wall-mount temperature transmitter powered by two AAA 1.5V alkaline batteries (not included), with normal life of about 1 year

Specifications:

Indoor temperature measuring range:
41° to 140°F with 0.2°F resolution
(5° to 60°C with 0.1°C resolution)
Outdoor temperature measuring range:
-21.8° to 157.8°F with 0.2°F resolution
(-29.9° to 69.9°C with 0.1°C resolution)
Temperature checking intervals:
Indoor: every 10 seconds
Outdoor: every 5 minutes
Transmission distance:
maximum 82 feet (25 meters)
Clock dimensions:
5.07 inches (12.9 cm) wide
3.66 inches (9.3 cm) high
2.0 inches (5.1 cm) deep (including base)
LCD display dimensions:
2.5 inches (6.35 cm) wide
1.5 inches (3.8 cm) high
Time number height: 0.75 inch (1.9 cm)
Remote transmitter dimensions:
1.625 inches (41 mm) wide
5.5 inches (138 mm) high
1 inch (25.4 mm) deep
Power source (for clock):
AC adapter (included):
120Vac, 60Hz input
6Vdc, 100mA output
Optional: three 1.5V AA alkaline batteries (not included)

Radio-controlled Time:

The NIST (National Institute of Standards and Technology, Time and Frequency Division) maintains a radio station, WWVB, in Ft. Collins, Colorado. The WWVB radio station derives its signal from the NIST atomic clock in Boulder, Colorado. A team of atomic physicists is continually measuring 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.

WWVB (the station’s identification just like any other radio station) continuously broadcasts time and frequency signals at 60 kHz. The carrier frequency provides a stable frequency reference traceable to the national standard. There are no voice announcements on the station, but a time code is synchronized with the 60 kHz carrier and is broadcast continuously at a rate of 1 bit per second using pulse width modulation. The time code contains the year, day of year, hour, minute, second, and flags that indicate the status of Daylight Saving Time, leap years, and leap seconds.

The La Crosse Technology WT-5432 Radio Controlled Projection Alarm Clock with Forecast Display:

The La Crosse Technology Radio Controlled Projection Alarm Clock with Forecast (and temperature) Display maintains its incredible accuracy by automatically tuning into the WWVB radio signal. The built-in antenna ensures reliable signal reception up to 2000 miles (3200km) from the WWVB transmitter. As a result, the La Crosse Technology clock will calibrate to the atomic clock not only throughout the mainland U.S. but also in much of Canada. You need only insert the batteries, wait until the signal is received, and program the desired additional settings. In locations outside of WWVB range, the LaCrosse clock can be manually set and will provide the high degree of accuracy of any quality quartz clock.

In a nutshell, here's how the the La Crosse clock works: The clock's antenna is specifically tuned for optimal reception of the 60 kHz time signal. The time signal received on the antenna is demodulated by an onboard receiver, which sends the information to the clock's CMOS microprocessor for decoding. Once your clock has automatically set its time for the first time, it ensures continuing accuracy by automatically tuning into the WWVB radio signal once per day at midnight. As long as your clock is kept within transmitter range, it will continue to display the absolutely precise time, automatically adjusting for summer time/winter time changeovers if the daylight savings time option is ON. Should you move your clock out of transmitter range for an extended period of time, the clock will continue to operate as a highly accurate quartz-controlled clock. Upon re-entering the transmitter range, your clock will correct itself again to the precise WWVB time signal.

This unit does not come with batteries. It requires 3 AA batteries for the clock and 2 AAA batteries for the remote temperature sender, which may be purchased below.

Note: This product has "atomic" clock functionality. Atomic, or Radio Controlled clocks receive a radio signal to set themselves. Like any radio receiver however, they may not be able to receive the signal if they are in a building with a lot of steel in the structure, near computers or other electrical equipment that may generate interference, or if the weather is unsuitable. The signal they receive does not propagate well during the day. That's the nature of the signal, not the clock. These clocks are designed to catch the signal when they can, generally in the middle of the night, calibrate themselves, and then run quite accurately for days until they can catch another signal. When you first put in the batteries, they will most likely not set themselves until the middle of the night. That's normal. By morning, weather permitting, it should be correct. Under less than ideal conditions, it could take a few days. Daylight savings time changes may not be made the first night if location and weather are not favorable.