I'm guessing you designed this — any advice as I embark on designing a second revision of my hiking log?
Additionally, when I do my designs, I place the BME280 sensor as far away from other components as possible (I see it is close to a SOIC chip on your board) and I route a cutout in the board around the sensor to reduce any heat conduction from the board. I also ensure that I have no power planes on the little resulting "island" PCB, and use small traces (with local decoupling) to further reduce any conductive heat. See the image in  for an example of what I am talking about.
Another alternative I pursued in situations where convective heat was an issue is to stick the sensor on a little remote board and use an off-the-shelf wire to connect the two (check out the Sparkfun Qwiic wires)
Overall you want to increase airflow around the sensor as much as possible so leaving it "hanging out" somewhere is the best approach to getting accurate measurements.
I hope that helps!
Are you sure it's the GPS module - 3 degrees sounds a lot for that? I'd try to take some measurements to confirm it before changing anything.
Which Feather board are you using?
There's only one "improvement" I would like to see - an option to buy a cheaper version without a display attached. For my application I will not need any display, and it seems a shame to spend resources on one when it's only going to get destroyed by the elements :)
I'm guessing a there is enough I/O left on a Pi 0w such that a CO2 sensor can be added to the Enviro+?
Doubt they're as capable or accurate but I'd be interested in hearing the reasons behind going with the pricier sensor if you've got time to share.
The MH-Z19 has a model specified for 0 to 2000 ppm so it might work fine. I don't know about the CCS811, the data sheet says it measures "equivalent" CO2, which is not a direct measurement, but a quantity inferred after measuring other compounds.
In the long run, there are calibration problems, as the photodetector ages. The best sensors have two light sources and automatically compensate for this effect. Indeed the other candidate I am considering is the Telaire 6615 which has dual sensors. My plan is to use the one of the two Telaires, preferably the dual sensor version, and correct measurements for temperature, pressure, and humidity. Hopefully, it will be accurate for a long time without the need for calibration with a known gas.
FWIW, I am just an amateur and welcome informed opinions. Scientific instruments that measure accurately in the atmospheric range are too pricey for me. The scientific community is just now starting to evaluate low cost sensors like the ones mentioned here, see  for a summary of some recent evaluations.
This looks interesting, but somehow it always seems wasteful to use full blown Linux servers for this stuff, so I'm dabbling in something smaller. :)
The HomelabOS project https://gitlab.com/NickBusey/HomelabOS is something I have been looking at. It would be neat if I could use a handful of Pis across the house wasting cycles for something like that in a kubernetes style fashion.
One other since you're the poster and presumably work at Pimoroni, is there a preferred distributor in the US?
Adafruit carry most of our range - hopefully they'll pick this up too soon!
Example being, the Touch pHAT (very good board btw) doesn’t use interrupts and library is sorta messy. I still use it though, because it’s not a big deal — however it’d be nice to be able to take full advantage of the components used in the boards. I guess my rant is mostly about not having access to some schematics of the products.
I don’t think this is exactly what I want, since it has an LCD, but the sensors and board are really cool.
The only thing I wish this tracked was SO2.
I’m thinking i might have to make my own with Arduino. But this is very cool.
We currently use In-situ Aqua Trolls to gather these parameters, but a solution like this could almost be considered disposable; hand them out to people in remote areas and you could potentially realise data for rivers/creeks that rarely flow, and would otherwise go unmonitored due to the time and finial investment required.
Very interesting project, thanks for sharing!
For measuring water parameters I would be tempted to use a rugged box for the Pi and then cable (via a removable connector) to something you put in the water. Basically design a probe like the device you linked. The fewer parts that need to be fully waterproof the eaiser life gets.
That sounds kind of limiting. I guess every hacker has old smartphone somewhere that can be used for that.
They are often easy to set up, but make sure to double-check just how much you can use your particular model for.
With an Enviro+ on a portable Pi I'll now be able to get my figures in near real time and ignore the Council.
Yes, for the price absolutely.
As building such boards is quite common, I too have assembled many similar boards for my own use, to monitor both indoors and outdoors air quality although I don't have any external stations to compare my values to but they're "calibrated" according to the same baseline across my setup and it allows me to keep an eye on different types of pollution - different gases, particulates, UV, noise and so on. Would be nice if all these platforms could be tied together.
(The zero is positioned as the "barest of bare-bones" to reach its price-point. Many vendors look for value-adds they can offer because there's not much margin on "barest of bare-bones". So "no headers" is one of the ways the manufacturing price was lowered, and "with headers" is one of the value-adds some vendors offer.)
So not to contradict anyone, just to be clear that you're looking for "pre-soldered" or "pre-soldered headers" if that convenience is worth the extra couple of bob to you - to avoid the disappointment of expecting one and receiving the other.
The Pi Zero comes in three flavours - the Pi Zero WH includes a pre-soldered header. :-)
Anyway, I should stress it wasn't a criticism - just that if that's their biggest question, they'd probably benefit from being able to tell the bare & WH boards apart.
Any idea when the PM sensors will be back in stock? I was thinking about grabbing one from elsewhere, but I imagine I need a cable pinout :)
Even better if there was a combined case which let you have the Raspberry Zero and this unit in one small thing.