La Crosse Technology WT-5120U Atomic Projection Alarm Clock with Indoor Temperature, Humidity and Wireless Outdoor Temperature

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La Crosse Technology WT-5120U
Atomic Projection Alarm Clock

The La Crosse Technology WT-5120U displays very accurate time, indoor temperature,  indoor humidity (rare in a projection clock), plus outdoor temperature on it's large LCD display In addition, the WT-5120U projects an alternating pattern of time and outdoor temperature on the ceiling or wall.

La Crosse Technology WT-5120 Atomic Projection Alarm Clock

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The La Crosse WT-5120U is attractively finished in silver with black trim.

Of course, like all La Crosse Atomic Clocks, the WT-5120U receives timing information from the U.S. Atomic Clock source, transmitted by the U.S. Commerce Department's  transmitter near Boulder Colorado.  You know the time will always be accurate, plus, the time can automatically adjust for Daylight Savings Time. 

Outdoor temperature information is transmitted to the WT-5120 by the included TX6U transmitter, which can be placed outdoors up to 80 feet away. 

The time and temperature projection display projects continuously when the included AC adapter is used.

The front LCD display has LED backlights that can be momentarily illuminated by depressing the snooze button.  When operating on batteries alone (without the AC adapter), touching the snooze button also activates the projected display.  

The La Crosse WT-5120U has single alarm functionality, with a snooze function.  The clock may be set for a single time, enabled or disabled.  When the alarm sounds, pressing the snooze button will silence the alarm for 10 minutes, at which time it will sound again.  It does not have dual alarm functionality, where a second time can also be programmed for use on other days of the week.


  • Clock displays hours (12 hour), minutes and seconds
  • Indoor Humidity (%RH) 
  • Wireless Outdoor Temperature (F) 
  • Indoor Temperature (F) 
  • Projects Time or Outdoor Temperature (alternating) on Wall or Ceiling in Easy to Read Numbers 
  • Projection & Arm Rotate for Proper Viewing 
  • Automatic Focus of Projection 
  • Atomic Time with Manual Setting 
  • Automatically Updates for Daylight Saving Time (On/Off Option) 
  • 12 Hour Time Display 
  • Time Zone Setting (12 zones, from GMT west to 2 zones West of Hawaii)  
  • Time Alarm with Snooze 
  • LED Backlight 
  • Free Standing 
  • AC Power Adapter Included 
  • Actual Size: 3.6" x 5.52" x 1.9" 


  • Digit size, Hours, Minutes 9/16" high, Temperature, Humidity, 7/16", seconds, 3/8"
  • Indoor Humidity Range: 1% to 99% 
  • Wireless Outdoor Temperature Range: -21.8F to 156.2F 
  • Indoor Temperature Range: 14F to 99.9F 
  • Projection Arm Rotates Up to 90 
  • Transmission Range: Up to 80 Feet 
  • Transmission Frequency: 433.92 MHz 
  • Power Requirements: 
    Clock: 2 "AA" Alkaline Batteries and/or AC Power Adapter (AC adapter included)
    Wireless Sensor: 2 "AA" Alkaline Batteries

Note:  This clock is intended for use in the 48 contiguous U.S. States, and Southwestern Canada.  Outside of this area, the clock can be set manually, but the signal will likely be too weak to reliably set the clock.

Like all Atomic clocks, the auto setting feature relies on the reception of a radio signal.  This signal can be interfered with by computers, lamp dimmers, other sources of electronic noise, bad weather conditions, and certain types of building construction.  In most locations, the signal will be received often enough that the time display will remain quite accurate.  There is a possibility, however, that DST time changes may not occur immediately if the location or weather are unfavorable.

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Availability: Exact quantity available will be displayed in the shopping cart, after you click the button below.

lacrwt5120uRegular price: $39.95Sale price: $24.95, 2/$48.00, 5/$110.00, 10/$210.00

If the order button is there, but the shopping cart page indicates that there are no units available, then we are temporarily out of stock.  The item should be available in a day or two.  Our inventory control system tries it's best to keep us from allowing the sale of something we don't have on the shelf. 

If there is no order button, most likely there are bigger problems with availability.  We may be out of stock for more than a few days.   

For shipping time estimates, please see the Fedex web site at  Your package will be shipped from zip code 60544.  Keep in mind, Fedex travel days do not include weekends or holidays.

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