@gohan Sorry, was thinking more of RF strength prog on a laptop, Acrylic or similar is used for wifi, just a thought...

here is the photo [image: 1504178388867-2017-08-31_13h02_14-resized.png]

Hello everyone Now it works very well, after changing the capacitor 4.7mF by a 10mF. Thank you again for your help. cordially Danie

@rejoe2 said in Compilation Error for Arduino Pro or Pro Mini: @Daniel-Ruiz According to my experience, it normally is not necessary to change sketches. Especially not as long as they are "official" MySensors Sketches. But as soon as additional libs are concerned (here: dallasTemperature), the developers may not be able to survey all external changes that may happen. (The conversionTime calculation had been "public" in the past; this had been changed for whatever reason by the dallas-lib-guys). So this sketch originally had worked. It also may have worked, if you installed an older version of the relevant lib (with the lib manager in the IDE). Nevertheless: You most likely already got a first idea how these things work. Me too, I had to fullfill a fast learning curve... BUT: It is fun! I fully agree with you. I have already assimilated some notions thanks to your experience. I'm going to hang on and move on. I love learning and discovering new technologies. I wish you a good evening. Daniel