Side view of the PCB balanced on the case. A basic resistance humidity sensor and separate temperature sensor stick out from the PCB as does a silver 4 legged co2 sensor at the top

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   Christopher M0YNG (m0yng@mastodon.radio)'s status on Monday, 08-Apr-2024 19:52:12 JST Christopher M0YNG

   Bought a cheap co2 monitor off eBay. The screen cover hides four screws, inside it looks suspiciously like there is space for an esp, although it's lacking the components to provide power and data. The pad marked 3v3 is 5v but the one marked vcc is 3.3v so could be tapped.
   The temperature and humidity sensors look pretty basic, not 100% on the co2 sensor
   There is no fan to draw air into the case
   The lithium cell's rating is hidden by the sticky pad.
   It doesn't seem to agree with my SCD4x sensor