[tomek_ycomb]

Excellent information from the person(s?) running air gradient with regards to pm sensor tech and design. Blog posts, etc.

Ranges of kits from pre assembled to solder-yourself, that HN might like.

(I am happy with my unit I gave to a friend with a wood fire stove heated house, and built one from kit to save some $ another time.)

[ds_opseeker]

I'll second air gradient. Founder is really cool and supportive. Tech works. I bought some boards from him a while back, ordered the parts of off alibaba, and had a working ESP32 setup in short order.