I use an arduino pro mini and i read A0 for values from a sct-013 30A/1V Non-invasive AC Current Sensor Clamp.
When i have the ethershield disconnected i read 0 values as i should (no ac power connected).
However when i connect the ethernetshield i immediately get values like 34-37 instead of 0 (possible analog values 0-1024).
I tried to place various capacitors between V5+ and ground and between A0 and ground without significant change. I powered the arduino from USB/PC and USB/power adapter without change. I also tried another ethernet shield but i didn't noticed anything different.
Can anyone suggest something to reduce the noise?