Hi,
using magnetic probe (it's 20 turn coil with a diameter of 2cm) I get much noisy of common and differential mode. To suppress the common mode noisy I used a ferrite ring with the wire twisted around it. To reduce the differential mode noisy what can I do?
Thanks in advance
Regards
Massi

 

Would be nice to see a schematic, or a picture of your project to help you diagnose the problem.

Differential signal processing should totally remove Common mode noise.

The differential noise may actually be more common mode noise picked up by your circuit after the difference amp.

We really need more info about how you are viewing your noise signals, where the signals are in the circuit you built, and what electrical devices are nearby your work space. You may just need shielding. Troubleshooting transient signals by remote conference while blind is not easy or accurate. Help us help you

 

Hi I think this sketch synthesize more or less the situation