This might be of interest to few out there. It is a sun and sky monitoring system that used to be sold by Radio Shack. Its been picked up by the Society for Amatuer Scientists who are selling the very last 40 odd that they have. Its only about USD$40.00 and looks to do all sorts of measurements.
I wasn’t going to order one, but then after thinking about it, we have so much haze and smoke in the air around here I thought it might be interesting to see what this instrument will tell me. I’m hoping it isn’t complicated to use, something I can use on a daily basis and add the readings to my website.
I wonder if WD will allow a user to add fields to the database, say an input like daily snow, where the station owner does a manual reading and then inputs that into WD, and that once added to the WD db can be graphed and added to the reports section.
Has anyone else thought about how to use the data this instrument provides?
I’ve been playing around with one - trust me, there’s nothing even remotely like a data stream to capture.
It’s basically 4 LED’s being used as sensors, connected to an op-amp and voltmeter. Literally less than $5.00 worth of parts.
However - and this is the big thing - it has an excellent manual, that describes both their theory and operation, and how you can measure haze, etc. Honestly, the manual is by far the best part.
You could gut the console and use it as a monitoring device, but, really, you’d be better off just homebrewing something specific to your needs, and retrieving the data via a 1-wire A/D.
I’d say that the value of the device as a whole is WELL WORTH what I paid for it. But don’t make the mistake of thinking that it’s some sort of automated system you can put to use right away, unless you already have a 2-axis rotator system to point the sensors directly at the sun, with a precision of a degree or less.
You asked about using LEDs that emit different colors. The short answer is yes, LEDs of different colors generally respond to similarly colored light. Thus, a green LED that emits at 525 nm or so will have a peak spectral response of about 505 nm. An exception to the rule are the blue LEDs made from gallium nitride (GaN) and related chemistries. Blue LEDs may have a very sharp detection response near 368 nm. Green GaN LEDs may have the same or similar detection response. While the main response is sharply tuned, there is a broad shoulder of reduced response extending into the green.
The spectral tuning available by using different kinds of LEDs forms the basis for the Radio Shack Sun and Sky Monitoring Station, which uses four different kinds of LEDs to detect wavelengths of about 505 nm, 625 nm, 816 nm and 930 nm. This very broad range of wavelengths from very simple, inexpensive LEDs permits this instrument to measure photosynthetic radiation (PAR) and to detect aerosols and the total column water vapor.