as per the topic’s title, I’m working on a Weather station (& Air Quality Measurement) board: taking inspiration from the sparkfun’s arduino weather shield (link) I started designing a board with a pressure sensor (BMP180), a temperature & humidity one (DHT22) and the RJ connections for the external rain & wind sensors like in the sparkfun board.
Browsing the forums I found this very nice thread… I had a lot of pins free, so I added some air quality measurement units. Now the board , powered @ 5V via USB or screw connector, is equipped with:
pressure sensor,temperature sensor, 2 RJ connectors as described above
a socket for MQ gas sensors a socket for TGS sensors (I’ll use a TGS2600)
a CO and NO2 sensor (MICS-4514)
3 GROVE style connectors (I2C, UART, GPIO)
1 (calibration?) button
after a lot of tinkering, the board is 90% defined, the layout looks like this:
In my plans there is also a small board with another sensor, an ozone one (MICS-2614) to use via the GROVE connector.
Up to now I did some software tests with the DHT & BMP sensors (I’m waiting to get the others) and everything works nicely.
Also the PCB routing is almost done, so I thought to share this project so that maybe some users could comment it, before I send the board to production
About that, I would like to use seeedstudio’s service, which gives you a minimum of 5 boards for each order: I am planning to keep/use/populare only 2 or 3 of them , so if somebody is interested in having one of them, I think it would be nice to give him a board :
I am also planning share the project (in a blog or something like that) when I’ll be able to have tested all the sensors that I’m waiting for.
Nice work!
In the other thread you linked to, they discussed some of the issues related to working with the DTH22. It is mentioned that it should be in an upright position, as well properly isolated from any and all heat sources. Perhaps you should take a second look at that, since the DTH is rather sensitive when it comes to heat.
hi there,
thanks for the reply: initially I thought to keep (and I will have anyhow space to do that) the DHT upright, but in minimum 1 of the 2 boards that I will populate I want to see if using airgaps works (the two “holes” around the DHT itself)
Being the board powered at 5V it should work, anyhow I will have also the BMP’s temp sensor as another reference or at least I hope!
Hi @Rockvole ,
to be honest… no
I didn’t want to spend hours searching for a suitable enclosure, mainly due to the fact that this is a personal project.
My idea is to have fun in designing a 3D printed enclosure once assembled the board
If in the future there will be any interest in the project which could led me to a 2nd version, this is definitely a thing that I will take into account.
I previously looked into detecting Ozone in the Indoor Air Quality shield, I concentrated on different sensors in the end.
From reading about it I thought it would be tricky to calibrate. You need to calibrate in air with 0 Ozone which is not so easy. So I thought the way would be to build a box with a carbon filter and a fan blowing into the box to filter the air so that you can get a reading to calibrate from.
I also read that the ozone sensor can be not so easy to calibrate, also in my case it was the reason why I didn’t include it in my board
But due to the fact that I had to order the MICS from the US, I “invested” 8 USD in getting it to make some tests… having a ADC channel unused in the design, I thought to make the “grove” peripheral for it.
Hi there,
just to update the thread: the board is finished (and ordered!) .
I played with the 3D model (using eagle cad, eagle3D and sketchup), the result looks like this:
PCB has been ordered, it will take some time to receive it, but I’ll keep updating this thread with my results.
As you may see from the image, I am setting up a blog - currently private - in order to track all my progress in this project.
I’m almost done with that, as soon as I will publish it I’ll write it here, with the blog address
(in the plans there is also a github page with all the SW and HW documents).
it would be very nice for me to share my project with someone else !
From my side there is no problem to give you a pcb (or a kit), this if my timings coincide with yours.
I am currently waiting for the PCBs to arrive, there are 5 of them in my order.
My plan is to populate (100%) 2 of them, I think that assembly will be finished within Easter.
If this sounds ok to you, I can “reserve” (of course without any committment from your side) one of these 2 boards for you.
In this case, I will ask you only the costs (plus shipping of course)
If you want just the PCB, again no problem for me.
I’ll keep you (and the thread) updated, thanks for your interest in my project!
Dear Cerocca, it is a nice board you have developed, please update on development and if I am interested can it be made available at some price? Best Regards
Hi @noman
unfortunately development is a bit stuck, mainly due to my lack of time .
I soldered all the components and made a functional test of the board, everything seems fine but I still have to do all the fine parts of the SW
if you are interested in a board, send me a PM and we’ll see what is possible to do!
Hello, what is the use of the PREH pin for the mics sensor ? I assume it is use to pre-heat the sensor, with a digital output.
Meaning you have to feed the mics sensor at 5V all the time, and when you want a value, you use this pin with a HIGH state for something like 30secs to heat and read the value of the resistance ?
Thanks for your answer
or at least I hope!
.
!