# Table of Measurement Annotations

Table of Measurement Annotations
Annotation | Description
--- | ---
* | An asterisk (*) before an measurement result indicates that correction factor value has been applied.The is usually the result of a setting in the Configure Measurements dialog box.
? | The measurement result is questionable. For example, the measurement may still be in progress or the algorithm cannot find a distinct peak in the histogram.
≥ | The measurement result is greater than or equal to the measurement algorithm of the waveform. The instrument uses this algorithm to calculate the result.
≤ | The measurement result is less than or equal to the resolution of the sampled points on the display graticule.
Base? | The measurement algorithm cannot find a distinct low (base) level in the signal.
Clipped | (Clipped high/low) The measurement algorithm cannot perform the measurement because the waveform extends past both the top and bottom edges of the display graticule.
Clipped hi | (Clipped high) The measurement algorithm cannot perform the measurement because the waveform extends past the top edge of the display graticule.
Clipped low | (Clipped low) The measurement algorithm cannot perform the measurement because the waveform extends past the bottom edge of the display graticule.
CorrFactor? | If an extinction ratio measurement has a correction factor value applied that results in an invalid measurement (negative value), the term "CorrFactor?" is shown on the Results tab instead of the measurement result.
Current | The current measured value for the corresponding measurement. The value is based upon the distribution of data points used for the measurement or the current value measured in the measurement database.
Dark level? | The dark level is invalid. The dark level is greater than the zero level of the eye diagram.
Edge? | The measurement algorithm cannot find the edge of the waveform needed to calculate measurement results.
Eye? | The measurement algorithm cannot perform the measurement because it cannot detect parameters typical of an eye diagram.
Incomplete | There has not been a sufficient number of data samples collected yet. This message can occur when performing measurements that require full use of all accumulated waveform data (for example, eye diagram measurements).
Maxima? | The measurement algorithm cannot find the maximum voltage (or power) of the waveform needed to calculate the measurement results.
Maximum | The value measured on the right side (largest numbered value) of the distribution used for the measurement or the maximum current value measured in the measurement database.
Mean | The average of the value reported in the Current column for the measurement.
Meas cancel | The measurement was cancelled through a remote command.
Minima? | The measurement algorithm cannot find the minimum voltage (or power) of the waveform needed to calculate the measurement results.
Minimum | The value measured on the left side (lowest numbered value) of the distribution used for the measurement or the minimum current value measured in the measurement database.
No Data | The measurement algorithm is unable to collect data.
Off screen | The measurement algorithm cannot perform the measurement because the waveform is not in the display graticule.
Pat. Length | The automatically detected pattern length of the data. This value can be manually entered.
Rate | The automatically estimated symbol rate of the data. This value can be manually entered.
SER? | Indicates that the initial SER measurement cannot be made, or already exceeds the target value. For example, this could be due to signal noise, or to the small signal level.
Source off | The source (input channel, waveform memory, or waveform function) is turned off during the measurement.
Source? | The measurement is performed on an invalid source. For example, a recalled color grade gray scale memory may no longer be valid.
Sources > 1 | The measurement algorithm cannot perform a measurement in color grade or grayscale display persistence mode when more than one source is turned on.
Standard Deviation | The measure of the distribution of the statistical average of the value reported in the Current column.
Timeout | The selected measurement takes longer than the time allotted for the measurement algorithm.
Top = Base | The signal has a too small amplitude and the measurement algorithm cannot detect the delta (D) between the top and base levels of the waveform. Therefore, the measurement results cannot be calculated.
Top? | The measurement algorithm cannot find a distinct high (top) level in the signal.
Total Meas | The total number of acquired waveforms.