I have a problem with a 1 kiloOhm potentiometer which is integrated in my stepper motor (for imaging).
When I connect it to Arduino and try the AnalogReadSerial example, the maximum voltage I measure is 3.8 Volt. Beside this, the digital value goes from 1023 to 249 or something like that. So it skips the first 249 units (or 249 * 0,0049 = 1,2 Volt).
I tried it also with only a 9V battery to exclude my Arduino doesn't work well. However, the same fault. Around 7V it goes to 0V again. However, I still measure the 1k Ohm at 7 Volt and 0 Ohm at 0Volt.
Yesterday everything worked fine with my Arduino in combination with the potentiometer. I measured from 0 until 5 Volt. Unfortunately this morning I got these problems.
Hope anyone could help me.