Hello, I have owned the SCK for two weeks and did several tests to find the best setup.
I am still investigating complex measurements like TVOC or PM, I started with simpler ones like temperature, humidity, and noise.
I am convinced that the design choice of putting the sensor board directly over the data board is the root cause of most problems. A cable connection, even short, would have been much more sensible.
Said that, the kit in practice needs to be used “open air” and in vertical position. Due to self heating of data board, and limited air circulation, horizontal position leads to errors of 2-3 degrees, in excess, on temperature. As the temperature and humidity values are used to correct other measurements, the impact of these errors is even greater.
Not all the vertical positions are equivalent, also. The best orientation is with the temperature sensor on the bottom, collecting air directly from below. In all the other positions, the air has to pass along to the data board before being measured, and this is enough to cause a 0.5 - 1 degree error.
I was able to compare SCK with a professional thermometer, 0.1 degree accurate, and with the setup suggested above, I found an agreement within 0.2 degrees. For same reasons, humidity measurement is a bit less accurate, I find a systematic error of 5 %, in defect.
About noise, basically the adopted sensor is not well suited for indoor measurements, having a minimum value of 45 dBa. In fact, I never measured less than 48 dBa, even in a dead silent room, because the power management chip, which is very close to the noise sensor, emits a multitone whistle in operation. I reduced the problem putting a felt disc above the “sounding” chip. This gave me additional 3 dBa of measurement range, reaching the 45 dBa limit.
As stated above, any enclosure worsens sensor performance. I tried some, but the sensor board needs to be in free air, both surfaces, so the only “enclosure” I am using is a sheet of plastic material, in vertical position, with the components fixed on the surface. For indoor use, this is acceptable.