Comments

Author Comment Last activity Moderation
cfastie "A 1/4" stereo/phone plug connects to the HCHO sensor and two wires from that cable connect to the Arduino (tip of plug to A3, ring to GND). Below (..." | Read more » almost 4 years ago
cfastie "The first step might be to arrange for the co-location of the HCHO sensor, an Arduino, and somebody casually familiar with Arduino. Has the proper ..." | Read more » almost 4 years ago
cfastie "Kina, Thanks for the great information. Liz, It might help to know more about this project. What is the time frame for deployment? What has been tr..." | Read more » almost 4 years ago
cfastie "Incandescent or halogen lamps emit lots of NIR. Fluorescent, sodium, mercury, and LED lamps do not. The image below is from here: http://perfecthea..." | Read more » almost 4 years ago
cfastie "There is a very simple way to read the HCHO sensor with a resolution of about 10 ppb, assuming the range of the sensor is 0 to 1000ppb. (Out of the..." | Read more » almost 4 years ago
cfastie "It is possible to compute a facsimile of NDVI from a single photo taken with a Pi NoIR camera and blue filter. The blue channel in the photo will c..." | Read more » almost 4 years ago
cfastie "There is no information at the Public Lab store about what filter is used except that it is a red filter. I suspect the filter is a Rosco `#19 filt..." | Read more » almost 4 years ago
cfastie "Blueish photos result when the blue channel is brighter than the other channels. Reddish or orangeish photos result when the red channel is brighte..." | Read more » almost 4 years ago
cfastie "The blue filters used block red light, so the red channel records a lot of NIR, so NGB. The red filters used block blue light, so the blue channel ..." | Read more » almost 4 years ago
cfastie "Probably good that they didn't contact me. I would have said only "Blue filter?" " | Read more » almost 4 years ago
cfastie "I think it is par for the course that a random proprietary sensor will not work gracefully with an Arduino. In this case, it might be that a standa..." | Read more » almost 4 years ago
cfastie "Any Arduino-based data logger should be able to read the signal from that sensor and save the reading at regular intervals. The main obstacle is th..." | Read more » almost 4 years ago
cfastie "Thanks Nick, The $9/month plan could work. It allows 20k checks per month, or one every 3 minutes which is more than we need. Multiple notification..." | Read more » almost 4 years ago
cfastie "That will be an interesting project to make a 5v Pro Mini data logger. I guess it will also include a 5v microSD module (the ones in the Mini Pearl..." | Read more » almost 4 years ago
cfastie "Ah, Arduino. Those DS3231 RTCs are designed to be used with a rechargeable coin cell (LIR2032) and they trickle current into the battery when curre..." | Read more » almost 4 years ago
cfastie "Whoops, I spoke too soon. The free offer at fluxguard is for "75 pages," but that means checking a page 75 times. So if I check the page every 15 m..." | Read more » almost 4 years ago
cfastie "Thanks Gretchen, I checked out versionista and they will check a site only three times a day. Nick suggested fluxguard which can check every 15 min..." | Read more » almost 4 years ago
cfastie "Thanks Nick, I just tested fluxguard and it works great. The test was on my own site (they are not spraying for mosquitoes now) but there is no ind..." | Read more » almost 4 years ago
cfastie "If that model is modified to allow for the components and the ribbon, it should be done so the new underside surfaces are not horizontal. FDM print..." | Read more » almost 4 years ago
cfastie "If you have a normal color photo and an NIR photo of the exact same scene, you can use the Photo Monitoring plugin for Fiji. The Github repository ..." | Read more » almost 4 years ago
cfastie "Near infrared light is the basis of vegetation indices like NDVI because healthy plant foliage reflects most NIR light and visible light is strongl..." | Read more » almost 4 years ago
cfastie "Wood moisture content is commonly measured at different points in the process of turning trees into finished wood products. Many wood moisture mete..." | Read more » almost 4 years ago
cfastie "I agree that the DFRobot TDS sensor looks like a useful device at a good price. My lame understanding is that this and other sensors which purport ..." | Read more » almost 4 years ago
cfastie "There is one part at Thingiverse. Is that the only one you need printed? The part at Thingiverse has a flat horizontal lower surface which could ca..." | Read more » almost 4 years ago