UPDATE 1:
Some parts have arived and i have verified that css811, sht3x, bh1750, ws2812b and ds18b20 is working. Buzzer still needs another revision to get it working also dht22, and ldr needs to be verified.
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UPDATE 2:
Parts i have verified : css811, sht3x, bh1750, ws2812b, ds18b20, ldr and dht22 is working.
Buzzer is not working!!
I have a limited run of 20 snos v4.2 boards for those who wants a:
- digital version (am312, ws2812b, sht30, bh1750, cs811, with external ds18b20)
- analog version (am312, ws2812b, dht22, ldr, with external ds18b20)
i going to make a form for those who want to order: pcb boards, assembled, enclosures.
price will be sent in approximately one week after you filled in the form. you then can confirm and place your order.
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UPDATE 3:
I looking for a solution to improve heatcreap to the temperature sensor its 5 degree Celsius off due the heat of the esp chip.
Solution will probably be a combination of vent holes in the case and sensor calibration
UPDATE 4:
i moved the sensor to the left side vertically instead horizontally on the top.
now i am within margin of error for actual temperature without case.
next is redesigning the enclosure.
what is your preference?
- little wider enclosure
- a bump on the side
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UPDATE 5:
seems that i have a strange behavior with the sht30 sensor that was proprobably not affected due heatcreap
same sensors left on breadboard right one on snos board.
as you can see the temperatures are the same until it suddenly creeps 7 degree higher.
sensors are inches from eachother.
i am still figuring this issue out!
I use these to avoid heat creep. A few vent holes to let the air in, a vent to mount the fan on for exhaust. They move just enough air to keep internal heat buildup down to a minimum but no so much that you get a cooling effect - especially if you wire them to a 3v source instead of 5v. Additionally, they use ball bearings instead of the cheaper sleeve bearings so they’ll last longer - hopefully 
.
I soldered so its on the side and put a heatsink on the pins so the heat is not going to the sensor but still facing he same issue… Going to try another mcu
Any updates?
UPDATE 6:
Yes i am working out all the bugs and then it is ready for prime time! 
I am so close of finishing! im hitting the limits of what is possible with a small esp8266 from what my sensor is capable of connecting 
And still learning a lot in pcb designing 
Its been a long time butt i had some personal health things that where a little more urgent 
butt things are moving again and you can expect updates in the near future!
UPDATE 7:
I am on the final design. the board works and the last change i now make is to have the sht30 (temperature sensor) move outside the enclosure to ensure 100% reliable temperatures.
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UPDATE 8: complete change of direction 
I am now totally changing my design and thoughts of this project. 
It was just not feasible to put all these requirements i have in a diy project.
- For a diy project it had too many solder joints in hard to reach places. also a 3d printed solder jig was needed and a correct solder sequence)
- The reliability of temperature sensor was a disaster and unable to compensate due the led and esp heat.
- Was getting more and more expensive and more difficult with each improvement i did to resolve the heat issue.
The way forward with this project is to make a fully integrated pcb.
This way it can be back to a more friendly price and the small enclosure i insisted on.
Also this gives me even more possibilities for the future 
Now working together with a professional pcb designer.
There will be less overall sensors and components for the same (actually better) results.
Beginner friendly and fast deployment, flash esphome or any preferred firmware and your ready.
Enclosure will be even smaller that will be more futureproof.
One sensor to rule them all! enitially thought of 3 versions:
- regular SNOS (this one)
- micro SNOS (one i teased here)
- SNOS with esp32
So hold on for a little longer… I know its been a while but this will be a HUGE improvement!
Thank you all and have a nice day/evening 
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UPDATE 9: PCB prototypes ordered
Prototype pcb’s are ordered and will be hopefully be delivered within 3 weeks time, together with all the components.
Also the enclosure is getting designed and previews will be coming very soon.
I sadly had to compromise on the usb serial due to space and price target, the boards can be programmed via a USB-to-Serial adapter, afterwards it is wirelessly flashable.
stay tuned!
UPDATE 10: PCB prototype testing
i have done some testing and everything works but there is some minor things i still have to refine and improve up-on.
- jtag error in the pcb traces (for recover flashing)
- test the dallas sensor (external temp sensor)
- improve the led in front so it stays visible in bright rooms and tweak the location
- improve the bme680 area on the board to improve faster response in rapid temperature changes (tested and seems on point to a 0.4degree celsius of an sht31d throughout 20-28 degree celsius)
- buzzer needs to get more volume for in large or louder rooms
- other minor tweaks for perfection
I am not giving any promises but i want the SNOS released by the end of 2021. that will be my goal!
stay tuned!
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Looking forward to it!
UPDATE 11: Final PCB revision ordered
As everything goes to planned i should be testing after a week or 3 max.
I made 2 versions of the sensor: a high precision and a regular version.
The differences are that the precision has the bme680 sensor sticking out the back where as the regular version has the sensor inside the enclosure.
- Precision version:
- For rooms that have rapid temperature changes
- Want to detect the temperature changes very fast for climate control (heating & cooling).
- Will never report false temperature’s due to led notification heat
- Not needing to configure an offset or almost none
- Regular version:
- Is more elegant and smaller
- Responds not as fast on rapid temperature changes due the esp heat or led notification heat
- Has all the sensors enclosed
yellow line is an SHT32 and the green line is the old regular SNOS sensor
- note that the new version of the regular should also be improved and precision should perform even better
The sensor will be getting certified for: Made for ESPHome
This will ensure the following:
- ESPHome configuration is open source
- Able to apply updates without coding changes required
stay tuned!
still have exciting updates and upgrades to announce
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