You can buy semipermeable membrane and add to your enclosure, Somebody at Ruuvi talked about it in a different post.
It seems birds like RuuviTag sticker 
It’s not so easy to find this kind of membrane but you can contact sales@ruuvi.com and we can figure out the problem.
"
I found a supplier for ruggedized TMP117 sensors, and 10 samples are underway in my direction.
Here are some images:
Connector wiring:
They are prepared to manufacture sensors with custom connectors - for instance, one that fits in the Ruuvi Pro.
@lauri @otso what about giving these a spin, have these produced with a matching connector, and added to your shop?
Those look really industrial-strength.
The manufacturer is:
Focus Sensing and Control Technology Co.,LTD
Add: No.1 XiSan Road, Electromechanical Industry Park ,
High&New Tech.Zone. Hefei,Anhui,China .PC. 230088
HP: +86-133-39106612
Whatsapp/Wechat: +86-133-39106612
Tel: +86-551-69109668
www.focusens.com
Email:info@focusens.com
Skype: melodyliu520
I suggest to talk to Melody Liu who was very forthcoming and quick to respond to my request.
Michael
This is an interesting product, we’ll take a look for sure. Thanks for the tip!
I will post my experience once I have the sensors
Ok, all parts arrived
I butchered the sensor cable and determined the wire colors as the relate to the signals on the connector in the image above:
now onto connecting the sensor to the Ruuvi board:
have you given any thought on how to bring out any sensor connector cable?
since the flat cable connector isnt of much use for this sensor, I’d solder the cable to pads at the PCB bottom
unfortunately that sits flush on the bottom part of the case - not sure how to do this
@otso which firmware should I use?
does the stock firmware support the TMP117?
btw I understand the sensor responds on the alternate I2C address
Thin flat cables come out from the enclosure without any issues. The cable you have is a way thicker and same idea cannot be used in this case.
Sorry about the bad photos but I think you’ll get the idea:
I see
my sensor will have a harsh life in this whale of a hot air balloon - temperatures up to 125°C and quite humid (ruuvi tag sits outside in a cooler environment) and when packing up the envelope there are quite some forces on the setup
so I thought the flat cable is not a realistic option and went for the Focusense sensor
just to convey the idea - mounting looks similar to this:
I guess I need to come in through the top of the case by drilling a hole and fastening the cable rigidly so it cant tear off that easily
one option would be a very short flat cable with some kind of breakout board to solder the TMP117 wires onto, all within the case above the PCB
btw the Focusense sensors are well built but the cable jacket material looks like it’s designed more for indoor applications - not particularly heat resistant. To use the TMP117 over its full temperature range a silicone or teflon cable would make sense.
I’ll cover the cable with a teflon hose just in case.
It turns out the humidity sensor in the breathable Ruuvi Pro in fact is very useful for balloon envelopes: if one packs up the envelope on wet ground and lets the bag sit during warm season for a few days there’s a good chance of mold developing which destroys the envelope for good. I think a humidity alarm from the tag will be super useful!
You might try
https://www.amazon.com/uxcell-Converter-Couple-Extend-Adapter/dp/B07RT6YS96/ref=pd_lpo_2?pd_rd_i=B07RT6YS96&psc=1
$7+
I got 2 and they seem to work mechanically ( for me I had to try a couple of times to line it up) Note that the ZIF receiver flips up as apposed to the ruuvi which slides out.
I haven’t connected anything to the board yet.
interesting idea, thanks!
we’re doing our own cases now, less hassle:
“we” is a bit of pluralis majestatis - it’s a talented chap named Vincent Amon and he’ll post here shortly
we might do another iteration with the adapter board as you suggested - I like the idea!
Here the first CAD tries of our Ruuvi Housing for the external Temperatur Sensor posted from @Michael_Haberler:
Project still ongoing.
we did pack up a ruuvi with an external TMP117 connected and are ready to run - but we need a hint: @otso @lauri 
see also: New project: External Ruuvi sensor boards - #48 by Michael_Haberler
we’re using both a ruuvi pro PCB, and the latest standard ruuvi boards in case that makes a difference
thanks in advance!
Michael & Vincent
Hello,
Based on picture, I think your board does not have TMP117 onboard. Latest production firmware 3.30.4 should work as-is on it.
Temperature sensor priority list is: TMP117, SHTC3, DPS310, BME280, nRF52, LIS2DH12. Other sensors will keep running to provide other sensor data. The broadcasted value comes from TMP117.
We made a special sensor comparison firmware which read every sensor separately and broadcasted the sensor values under unique MAC addresses, but it’s meant only for verifying sensor accuracy and does not suit any production use-case.
thanks - so that one should work out-of-the box if it detects the TMP117 - easy!
before I dig into the repo… is the PCB board temperature also reported from one of the other sensors? that’d be interesting given our peculiar mounting position
sure the humidity and pressure sensors report temperature as well, just a question if one of those makes it into the manufacturer data vector
yes, that particular image shows a non-Pro board.
What happens if we connect a TMP117 externally to a pro board? the external TMP117 sensor answers on I2C 0x49
hope this works, I’d love to get by with stock firmware
thanks!
Michael
ps: can I tack on a suggestion re the manufacturer data format:
instead of going through X versions of tagged C structs, why dont you switch to the self-describing protobuf format? it’s already in the SDK (nanopb) and great Finnish software btw!
that opens the route to arbitrary sensor data being tacked on and it would be backwards compatible, which your current method is not
Regrettably no, although creating a custom data format is relatively easy.
As of current firmware, external TMP117 will drain energy while not getting read by the firmware. We have detecting different I2C addresses on our roadmap, but I cannot make promises about the schedule. Line to be changed is here.
I’d love to, but BLE advertisements limit what we can do quite a lot. The communication is broadcast, many-to-one with no guarantees about data delivery and payload is at maximum 24 bytes. It’s not possible to pack as much information as we do into a more flexible format.
mission accomplished!
@vincentamon has successfully integrated the Focusense TMP117 sensor with a ruuvi tag:
some detail shots:
pinout:
Software: the only changed required was the I2C address change suggested by @otso above
Michael
Wonderful and well illustrated too. 
@Michael_Haberler Thats a very nice project. I have one for 4WD shock absorbers to implement. So will follow your lead with focusence. we have an office in China. How easy is it to make the firmware change you listed? What is battery life expectancy? Cheers and thanks again
software is the stock ruuvi repository, with a single change - modifying the I2C address of the sensor and recompiling - so for battery use, the rules for the stock software apply
all pretty straightforward - @vincentamon did this
I’ll see into having the repo published with instructions
for contacting Focusense, see the coordinates above - contact Mrs Melody Liu, she’ll be in the know
by now we have about 250 Focusense TMP117 sensors wired
Focusense made changes to cabling on our request (heat resistance, length, no plug)
all of them working - decent product, recommended
company easy and reliable to work with
Thanks for the update, this is great info 
