La Crosse WT-5130U Atomic Projection Alarm Clock

The La Crosse WT-5130U Advanced Atomic Projection Alarm Clock offers lots of useful features. In addition to the time, it displays indoor temperature and humidity, outdoor temperature, and two forecast icons plus a tendency arrow. The clock also alternately projects the time and outdoor temperature on the wall or ceiling. The daily alarm has a 10-minute snooze function. The clock's large, 2-line LCD  panel has a blue electro-luminescent backlight for night viewing. Included with the WT-5130U is a TX6U wireless remote sensor/transmitter that reports the outdoor temperature to the main unit.

The WT-5130U displays the time as hours, minutes, and seconds. For the time format, you can select 12-hour with PM, or 24-hour. The alarm is a single daily alarm with 2-minute duration and available 10-minute snooze.

Temperatures can be displayed in °F or °C, and indoor relative humidity is displayed in percent. If you wish, you can press the Set/+/Min button to display the alarm time, the month and date, or the weekday and date in place of indoor temperature and humidity.

Just so you know, the hour and minute digits in the LCD panel are 9/16 inch tall, seconds are 3/8 inch, and temperatures and humidity are 7/16 inch (tenths of a degree are smaller). Also, the LCD contrast can be adjusted for eight different levels. The LCD panel's blue electro-luminescent backlight is activated by pressing any pushbutton or the Snooze/Advance Mode bar on the top of the clock. Backlight duration is about 10 seconds with auto-off.

The WT-5130U provides accurate weather forecasts by means of its various icons and a barometric pressure-based weather tendency arrow. The weather-forecasting feature senses barometric pressure over time and adjusts the icons to provide accurate forecasts based on pressure trends. For example, if the sunny or cloudy icon is displayed with a downward tendency arrow, this means that the pressure has dropped and the weather is expected to worsen. If the cloudy or rainy icon is displayed with an upward tendency arrow, this means that the pressure has risen and the weather is expected to improve. The forecasts are about 75% accurate for 12 to 24 hours.

The Weather Boy icon in the display is something new. A total of 15 different Weather Boy icons can be displayed. Each is based on the pressure changes detected by the main unit and the outdoor temperature measured by the remote sensor. The way Weather Boy is dressed, and in some cases the umbrella in his hand or the snowman and snowflakes behind him, suggests how you should dress for current weather conditions. 

When the WT-5130U is powered from the included ac adapter, projection is continuous and the time and outdoor temperature are projected alternately for about 7 seconds each. When the clock is battery powered (two AA), projection is activated by pressing the Snooze/Advance Mode bar, and projection duration is about 7 seconds with auto-off. The projected image alternates between time and outdoor temperature with each press of the bar. The WT-5130U's projection unit tilts a full 180° so that the image can be projected not only upward but also to the front or back as desired. Also, the projected image can be rotated 360° in 90° increments by pressing the directional button (the small middle button on the front). The projector auto-focuses for display from 3 to 6 feet away.

With a base that's an integral part of its case, the WT-5130U is designed to rest on a nightstand, table, shelf, or other horizontal surface. This clock cannot be wall mounted.

Features and Functions:

• Sets automatically to WWVB radio signal (manual setting is also possible).
• User-selectable time format:12-hour with PM, or or 24-hour.
• Time is displayed as hour, minutes, and seconds.
• Indoor and outdoor temperatures can be displayed in °F or °C.
• The TX6U outdoor/remote temperature sensor/transmitter (433MHz) is included.
• Indoor relative humidity is displayed in %.
• Alarm time, calendar month and date, or weekday and date can be displayed as an alternative to indoor temperature and humidity.
• Thirteen available time zone settings: GMT (0) and -1 through -12.
• Daylight saving time ON/OFF option.
• With battery powering, projection is initiated by pressing a bar on clock's top and is 7 seconds in duration. Projected image alternates between time and outdoor temperature with each press of the bar.
• With ac powering from included adapter, projection is continuous. Time and outdoor temperature alternate every 7 seconds.
• Projection auto-focuses for display from 3 to 6 feet away on ceiling or wall (the projected image can only be seen in the dark).
• Projected display can be rotated 360° in 90° increments for proper viewing.
• Projector case rotates 180° to further orient the projected display.
• Three weather-forecast icons (sunny, partly cloudy, and rainy) with tendency arrows.
• Fifteen different Weather Boy icons provide suggestions on how to dress for current weather conditions.
• Single daily alarm sounds for 120 seconds, speeding up after 20 seconds and again after 50 seconds unless turned off via pushbutton or Snooze/Advance Mode bar.
• Pressing Snooze/Advance Mode bar with alarm sounding turns alarm off for 10 minutes, after which alarm sounds again.
• Pressing any button except directional button and Snooze/Advance Mode bar with alarm sounding turns alarm off for 24 hours.
• Blue electro-luminescent backlight for LCD panel (10-second duration, initiated by pressing any pushbutton).
• LCD contrast is adjustable for 8 levels.
• Integral base for placement on nightstand or other horizontal surface.
• Clock can be powered either by ac adapter (included) or by two AA 1.5V alkaline batteries (not included). Normal battery life is up to 18 months, but battery life can be shortened by excessive projector and backlight use.
• TX6U remote temperature transmitter is powered by two AA 1.5V alkaline batteries (not included), with normal life of about 1 year. Lithium batteries are recommended instead of AA for use in sub-freezing temperatures.

• Indoor temperature measuring range:
  14° to 98.4°F with 0.2°F resolution
  (-10° to 36.8°C with 0.2°C resolution)
• Outdoor temperature measuring range:
  -22° to 157.8°F with 0.2°F resolution
  (-30° to 69.9°C with 0.1°C resolution)
• Temperature checking intervals:
  Indoor: every 15 seconds
  Outdoor: every 5 minutes
• Transmission distance:
  maximum 100 feet (30 meters) in open space with no interference
• Indoor humidity measuring range:
  0 to 99%
• Indoor humidity checking interval:
  Every 20 seconds
• Clock dimensions:
  6.5 inches (165 mm) wide
  3.6 inches (91 mm) high
  2.0 inches (51 mm) deep (including base)
• LCD display dimensions:
  3.5 inches (89 mm) wide
  1.5 inches (38 mm) high
• Remote transmitter dimensions:
  1.57 inches (40 mm) wide
  5.04 inches (128 mm) high
  0.9 inch (23 mm) deep
• Power source for clock:
  AC adapter (included):
  120Vac, 60Hz input
  3.4Vdc, 50mA output
  Optional: two 1.5V AA alkaline batteries (not included)
• Power source for TX6U remote:
  Two 1.5V AA alkaline batteries (not included). Lithium AA batteries are recommended instead of alkaline for use in sub-freezing temperatures.

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-5130U Atomic Clock:

The La Crosse Technology Radio-Controlled Clock 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 battery, press the appropriate time zone button, and wait until the signal is received (overnight). In all other locations worldwide, the La Crosse 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 after midnight. As long as your clock is kept within transmitter range, it will continue to display the absolutely precise time, even automatically adjusting for summer time/winter time changeovers. 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.