@Sullivan-Buchs thanks for your code, quiet unique piece. The only working one I found!
I changed the hardware a little to use the TX led from the same sensor board.
Sended a pull request, if you prefer to adopt it.
@hek we have plenty of hydro alcoholic gel available here in Vietnam, and they all contain ethanol and not IPA, which is a skin irritant and doesn't seem to be a good idea to use for hand sanitizer as you need high concentration for alcohol to be efficient on the virus. You should change the recipe of your "quick and easy" version, to use ethanol as recommended by WHO.
For the survival of the virus new studies show a survival up to 3 days on some surfaces like inox. But that's the best case scenario for the virus, on most surfaces and in most conditions it seems it will just die in a matter of hours. So unless you have a very fast shipping (would be surprising with the number of international flights plummeting), you have nothing to fear.
And now the main risk if you are in the US, EU etc is probably from the employees of the delivery company, as there are probably way more active cases in the US/EU than in China outside of the Hubei province. So when you receive a package, open it outside, get rid of the packaging, and if you're paranoid let it wait a few days in garage/storage room. Then wash your hands carefully, and you risk nothing.
@Anthalas CO2 concentration at the fermentation trap outlet could work once you calibrate it, but a simpler method would be listening or watching for bubbles passing in a minute or less, hear them check again tomorrow or in 12 hours, hear none call ET, it's party time?
I used to open the cupboard and look, but that was in the days of black and white when caves were caves, but still a tried and tested technique if it doesn't work
The main goal of this board is to offer a simple way to build any kind (RFM69 and NRF24 support, MYSX connector) of compact battery powered node.
Today I have finished the first node based on this board: a door window sensor (reed switch).
If someone is interested, here the detailed build instructions.
The next node based on this board will be a soil moisture sensor!