My wife surprised me this Xmas with a gift that I have been wanting for years: a wireless thermometer. I know it doesn't sound all that exciting, but for a wireless geek like me, it was special. It has a base station unit with a big LCD readout that shows temperature inside and at two remote locations as well as time and barometric pressure. I have had electronic thermometers in the past, but they always had a cable or attachment from the sensor to the readout. That always meant stringing that connection through a window and over a very limited range. With this wireless unit, the sensor is in its own housing and can be located as far as 300 feet away from the base station. It uses the 433 MHz ISM band for digital transmission of the temperature. My unit has two sensors.
I love this thing. I can now always know the temperature inside as well as outside and at one other point I choose. I couldn't have imagined how much I refer to the temperature. And the built-in clock is automatically set by the time signals from NIST station WWVB in Boulder, Colorado. This is the time station that operates on 60 kHz...yes, that is correct: 60 kHz. It transmits with mucho kilowatts via an enormous antenna and has a range that pretty much covers the continental U.S. So the clock inside my unit is dead-on accurate since it is constantly updated to correspond to an atomic clock in Boulder.
My unit was made by Oregon Scientific, but there are many others and they are cheap. Any Home Depot or Lowe's has them in stock.
A merry wireless Xmas indeed.