GE Ultrasonic USM Go, Руководство оператора

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Chapter 3. Making Measurements
100 USM Go Operator’s Manual
3.13.4 Evaluating Results in DGS Mode
After the DGS curve is recorded and displayed, by turning DGS mode ON , echoes are automatically compared to the recorded reference.
There are three ways this comparison can be made and two additional DGS -related results that can be displayed:
•
A%rA
- Amplitude of the signal crossing Gate A as a percentage of the corresponding DGS curve amplitude.
•
dBrA
- dB equivalent height difference between the signal crossing Gate A and the corresponding DGS curve height.
•
ERS
- Evaluates the reflected echo and calculates the Equivalent Reflector Size .
•
Gt
- DGS test gain, which initializes the DGS curve maximum height at 80% FSH.
•
Gr
- DGS reference gain, which represents the instrument gain at which the reference echo peak reaches 80% FSH.
To aid in interpreting the DGS mode display, the instrument displays up to four curves representing fixed-gain offsets from the DGS curve.
These curves are enabled and positioned, by specifying the dB-equivalent amount they are offset above or below the DGS curve, by
accessing the OFFSETS submenu in the DGS menu.