I have no affiliation with Air Gradient (who wrote TFA) but I recently assembled one of their DIY devices (the Pro Pre-soldered version) and I'm quite happy wit

I have no affiliation with Air Gradient (who wrote TFA) but I recently assembled one of their DIY devices (the Pro Pre-soldered version) and I'm quite happy with it. > Since the AirGradient DIY Pro Kits are fully open-cource [sic] you can send the data to any server, i.e. Home Assistant If you can put lego together you can assemble this device, and the price is right IMO, especially compared to competitors. I don't think it's as compact or good looking as an Aranet 4, and it's not portable unless you use a battery bank, but's it half the price. https://www.airgradient.com/kits/ https://www.airgradient.com/kits/