tomasdelaveau:
I could only use the MAX6675 after changing the pin for the CLK of this module, ie. to a different pin than the CLK of the nRF24L01. Why are they supposed to be the same if it works better by using different pins?
You will have to study the MAX6675 library and datasheet closely to figure that one out. My wild guess is that te author did not take the trouble to write the library with a view to compatibility with normal SPI usage.
...R