An electronic device has been devised in order to measure simultaneously the potential fluctuations and the electrolyte resistance fluctuations of an electrode. The separation of the ohmic and faradaic components of the potential fluctuations allows a more precise identification of the elementary events generating this voltage electrochemical noise (bubble detachment on a gas‐evolving electrode, contact between particles in a fluidized electrode, etc.). Transients of the electrolyte resistance as fast as 1 ms can be measured by this device with a precision better than 0.1%.