3 ms·
I have used the MH-Z19 [1] $10 real CO2 sensors for a bunch of things. They appear to work well, although I have no ability to measure the accuracy of the res
by londons_explore 2y ago
I have used the MH-Z19 [1] $10 real CO2 sensors for a bunch of things. They appear to work well, although I have no ability to measure the accuracy of the results.
I do have a 'one day when I get free time' plan to make new firmware for them to also measure moisture and a bunch of other VOC's which have unique absorption spectra in the 800-2000nm range, since the hardware itself can be abused as a poor-man's spectrometer.
[1]: https://www.aliexpress.com/w/wholesale-z19-co2.html https://www.aliexpress.com/w/wholesale-z19-co2.html?
- IgorPartola 2y agoThere is a way to program these?
- londons_explore 2y agothey're just ST microcontrollers. you can put your own firmware on and do what you like with the hardware. The hardware consists of an incandescent bulb and photodiode with amplifier and high res ADC. The bulb and photodiode sit in a box with a silvered interior, which allows light from the bulb to reflect around inside the box a lot (and having some light absorbed by CO2) before hitting the photodiode.