August 19, 2011
News - Hacker-in-Residence: Envi…
Hey, how about another idea to get women interested in electronics? Say a jacket rather than a puppet. The jacket can light up at night for safety, react to the environment (temp, humidity, air quality, noise, etc.), sniff out wi-fi spots, have a built in alarm system, or pair with a smart phone to provide real time updates? The advantage of a jacket is that since it will be worn out in the real world, it has the potential for a lot more people to be encouraged to start ‘making’… Just a thought….
about a year ago
Sorry for the noob question here, but could this be used to measure outdoor humidity (I’m in Florida where humidity routinely reaches 100%)? I’m assuming I’d need some sort of enclosure to isolate this sensor from my Arduino (since I try to keep it as dry as possible). I’ve been using the outdoor version of a DHT22 and they are only lasting about 4 months before they start reading 100% RH (and yes, I’ve tried the reconditioning process). Any input would be greatly appreciated! Thanks!
about 2 years ago
I think a terrific ‘companion’ to this product would be a nice plastic case. Something that brings the buttons to the outside of the case and maybe an option for either ‘clear’ or black.
about 2 years ago
Not sure if this is the right solution or not, but I got the I2C interface to work between this breakout and the Arduino Pro Mini 5V by changing the following items from bildr blog for the TMP102 breakout board:
1.) Created a voltage divider using a 10k and a 22K resistor to convert 5v down to 3.4 v. (for VCC on the TMP102 breakout board) This is just a temporary solution since I didn’t have a 3.3 voltage regulator handy.
2.) Soldering wires to the unpopulated A4 and A5 pins on the Pro Mini and adding a 1K pull up resistor to each pin. I connected the pullup resistor to the 5v power supply. It wouldn’t work connected to 3.3v.
How do I get this board to work with a Sparkfun Pro Mini (5V)?
It works just fine on an Uno. I’m using a voltage divider to reduce current on V+ to 3.3v. I’m guessing that it has to do something with needing to add pullup resistors on A4 and A5 or possibly converting the current to 5v on A4 and A5, but can’t seem to find a wiring diagram on how to do that.
about 2 years ago
Good news. I ran my first ‘real world’ test against a rainstorm last night. Weather.com reported .40 inches (they round to the nearest .05), and using the ‘0.014814815’ factor above, I recorded .44 inches of rain. I’m pretty happy with that result.
Great! This sounds like progress to me. Seems as if our calculations about the number of ounces needed to get an inch of rain now match up to mine. Please post your revised ‘rain inches per bucket dump’ number when you get a chance. I’m really hoping I’m not crazy and it’s close to ‘0.014814815’.
How did you come up with an opening area of that size? Has the rain gauge changed in size? The opening for the one I purchased from Sparkfun is 1 7/8" x 4 ¼". That’s about 8 square inches.
Hey Mike. Thanks for the feedback. I ran 8 oz of water and got 135 bucket tips. So, while your ‘rainfall per bucket tip’ number is ‘0.0086206896’, mine turns out to be about double that at ‘0.014814815’. Is there any chance you can run 8 oz through your gauge and give me your bucket count?
So, check this out. When I dump 8 Oz of water into the sensor (as fast as it will take it), the gauge registers .8 inches of rain. Turns out, that rate is the equivalent of 30 inches an hour (probably over-loading the gauge). The max a hurricane can deliver is about 6 inches an hour. Plus, at 8 oz. of water, I’m expecting it to register 2" of rain, not .8. Oh joy!
On the advice of a friend, I drilled a couple of holes in an unused jar of peanut butter (one of my favorite scientific instruments by the way) using a 1/16" drill bit. Now, 8 Oz. registers 1.33 inches of rain (at a rate of 30 inches an hour). This is still raining faster than a hurricane, so I’m guessing that I’m still overloading the gauge. Next, I use a needle to create the smallest hole I can possibly imagine. Now, I get 1.43 inches of rain of a rate of about 5.5 inches per hour. I’m unsure on how to make it any slower. But, the good news is that multiple tests yield about the same results. Only, mathematically, 8 oz of water should be 2 inches of rain, not 1.43. So, I’m still stumped…
Mike, thanks again for the feedback!
Thanks MikeG. Great suggestion, only, I’m not exactly sure my math is entirely accurate. My gut says that my math is off, not the meter (nor my debounce code). Math isn’t exactly my strong suit. Has anyone else tried to verify the accuracy of this device?
No public wish lists :(
Forgot your password?
No account? Register one!