This setting allows attenuating the signal by factor of 10 if its dynamic range exceeds ±5 V. 1x, 10x and AUTO attenuation options are available. If AUTO is selected then first sample of any voltage measurement (including the ones performed during Autoset and Auto-trigger) will be analyzed to determine the dynamic range of the signal. If the range exceeds ±5 V then 10x attenuation will be switched on automatically. 1x will be used otherwise.