from adafruit.com/xbee this is one half of a two-way radio data link. photo: oly e3, 50mm f2.0 macro lens, raw capture mode and 2 passes of ‘neatimage’ for noise reduction (gives it that almost-synthetic clean look). subject was shot inside a DIY lightbox with a sheet of black plastic (ABS) as the base.
What is a temperature sensor? An analog temperature sensor is pretty easy to explain, its a chip that tells you what the ambient temperature is!
These sensors use a solid-state technique to determine the temperature. That is to say, they dont use mercury (like old thermometers), bimetalic strips (like in some home thermometers or stoves), nor do they use thermistors (temperature sensitive resistors). Instead, they use the fact as temperature increases, the votage across a diode increases at a known rate. (Technically, this is actually the voltage drop between the base and emitter – the Vbe – of a transistor. By precisely amplifying the voltage change, it is easy to genereate an analog signal that is directly proportional to temperature. There have been some improvements on the technique but, essentially that is how temperature is measured.
Because these sensors have no moving parts, they are precise, never wear out, don’t need calibration, work under many environmental conditions, and are consistant between sensors and readings. Moreover they are very inexpensive and quite easy to use…
Some basic stats
These stats are for the temperature in the Adafruit shop, the Analog Devices TMP36 (-40 to 150C). Its very similar to the LM35/TMP35 (celsius output) and LM34/TMP34 (farenheit output). The reason we went with the ’36 instead of the ’35 or ’34 is that this sensor has a very wide range and doensn’t require a negative voltage to read sub-zero temperatures. Otherwise, the functionality is basically the same.
Size: TO-92 package (about 0.2″ x 0.2″ x 0.2″) with three leads
Taters is an audio memory box I made as a gift for my beautiful wife. When you pick him up and tilt him right, he says compliments. Tilt him left, and he tells funny stories. Tilt him forward and he may kiss you or vomit. Lay him down, and he goes to sleep and starts snoring. I made audio recordings of Anne’s friends for most of the comments. Also, if left alone for too long, he becomes bored and will say/do things on his own, like breaking glass or playing with a squeaky ball.
Paul and I are leaving on a cross-country train trip next week, for Jen and Shawn’s wedding in Colorado. I’m sure the view will be great, and I’m bringing a handful of books- but Paul and I are geeks and we need our electro-doodads. If only we had a way to run our Nintendo DS and PSP for the ~30 hours that the trip will take…
I sifted through my stockpile of junk, and came up with this: It’s kind of like a mega-size Minty Boost, or a heftier version of the Kensington power pack. The Minty Boost weighs in at about 6 Watt-hours, depending on the AA cells you use. The Kensington pack is rated at 7 Watt-hours, with a Lithium Ion battery. This brick occupies the middle-ground between the Minty Boost and a car jump-start battery, weighing in at 84 Watt-hours. It should run and charge a Nintendo DS for at least 30 hours.