[werk_ag]

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I have tested your suggestion this evening. Sadly I get the same results however. The test code works fine even when run off the WeatherDuino board, but the TX software does not. At least I know it is not the circuitboard at fault.
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That was my intention, try to eliminate anything which could be related to the TX board.
I checked everything again with the TX software, also tried with the library you provide. In both cases I can read the DHT22 sensor attached to the Pro2 TX board.

Here are some pictures:


With the original Pro2 TX firmware v7.0_b003:




Using the example from the DHT library you sent:




Picture of connections:



It like these mysteries, but at moment I haven't a single clue about why your sensor isn't being read properly.
Can you please post your whole Config_Options.h file so I could test with exactly the same config.

Rgs.
Werk_AG