My pleasure.

Electrochemical sensors have a lifespan of about 2 years, so that particular formaldehyde cell should be replaced. No, the alarm is not from that. A firmware update would help: https://www.uradmonitor.com/blog/?s=firmware

Sounds good! What HVDC did you use?

Would love to see this setup, do you have pictures?

What’s next in your project?

We did tests with many GM tubes in parallel. Here is one example: https://www.pocketmagic.net/city-air-quality/

This increases detector capacity, so what you need to do is to adjust the compensation capacitor. It is explained here: https://www.uradmonitor.com/compensation-capacitor/

Please include some snapshots with the two devices, from their internal webpage.

Thanks. Please do a smoke test, burn a little piece of paper and right when the sensor goes into “Running” mode, Blow to extinguish the flame and send a little smoke towards the sensor. Do that for a few seconds . Take a new snapshot with what you see .

Hi Newt, do you hear the fan when the unit is running? (Green Label on internal webpage, not the red “Idle” visible in your posts?)