On older versions of MP500 firmware, the LMA detection algorithm does not account for clipping due to over-range conditions. The algorithm searches for LMA on clipped voltages which exceed the vertical range of the Analog In port. Eventually it may find something that appears like LMA, but since the voltage is clipped, it detects the peak of the clipped value as the amplitude. Since this peak amplitude is the top of the measurement window (vertical range), as that value doubles, so does the "measured" LMA value. This pattern will continue until the over-range condition is no longer present.
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