try to find one WITH that filter in China btw
I have the non-filter version even in stock … and today arrived the hand soldering RF switches
I’m still looking for SHT31-D with the PTFE film for outdoor application but for non-professional($) applications €17 is just (much) too high. (3+ weeks patience for delivery is not an issue in that case).
don’t be fooled by the ‘simplicity’… these caps or filters are hard to get and expensive
https://www.sensirion.com/en/environmental-sensors/humidity-sensors/filter-cap-sf2/
I know they are difficult to get: The WORKBENCH
But it would be unusual if the PTFE membrane film would cost more than the SHT31-D chip itself.
Updated link for the SHT3x Filter Membrane Datasheet
SHT31-DIS-B is the standard chip (without membrane)
SHT31-DIS-F is the chip with membrane film included
I agree off course, but he… some manufacturers (like apple for example ) don’t look at what all the components together would cost + manufacturing + profit… they estimate what a user would want to pay max for it.
and maybe its extremely difficult to produce filters that fine… I don’t know (or care for that matter… I needed only one )
On tindie user “closedcube” offers a version with a “SF2 filter cap” option which only adds 1.95$
Is that what you are looking for ?
under construction
testing the ‘toolchain’… hello world 
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I have this idea to build an airquality (LoRaWan mobile) sensor where the actual sensors (CO2/temp/hum/particle ect) are inside a controlled environment .
parts I allready ordered for this try before you die project:
mini air valves 2x - https://www.ebay.com/itm/Electric-DC-Solenoid-Valve-DC-3V-N-C-Normally-Closed-For-Gas-Air-Valve-Mini/302473142935
valve control 2x - https://www.ebay.com/itm/DC-3V-6V-6A-Single-key-Bistable-Circuit-Module-Self-locking-Switch-Trigger-Relay/322792973310
air pump - https://www.ebay.com/itm/DC-3V-5V-6V-High-Pressure-Mini-Diaphragm-Self-Priming-Water-Pump-Vacuum-Air-Pump/263606545715
soft tubing - https://www.ebay.com/itm/Clear-Silicone-Translucent-Soft-Rubber-Tube-Flexible-Hose-Food-Grade-Pipe-2-15mm/263584063711
tube connector 2x - https://www.ebay.com/itm/Brass-G1-4-Thread-Soft-Tube-Hose-Connector-for-PC-Computer-Water-Cooling-System/132492072174
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I’ll publish the differences in a blog post later. Mostly optimization and polishing. 
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I know I just reached 13 km on SF7
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Nice enclosure.
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Thanks. I am looking more for something like this but in module form:
SHT31-DIS-F (@Mouser)
Mouser price is €2.69 per chip (1000+) which is only €0.26 more than the version without the membrane film.
Based on the prices for Chinese SHT31-D (SHT31-DIS-B) modules starting from €3,47 I think that a (Chinese) SHT31-DIS-F based module with membrane film for around €4 to €5 should be feasible.
So it just may take some time before cheaper modules become available.
I actually meant the other enclosure with the grill. 
the idea is to put the node electronics/battery inside enclosure 1 and the sensor free in that Stevenson enclosure… Im waiting for the glue to dry 
this node works even when the battery drops to ONE volt …
can be used in and outdoors
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2 gateways down… 
A couple of suggestions for you. If all the electronic components are on the top of the board, then consider mounting the board upside down as this will help in the event of condensation. Apply conformal coating to the board but take care to avoid blocking sensor holes/vents.
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the sensor module has a filter so I think I have to be very carefull applying some coating to the board.
what coating / spray do you suggest … something like this ?