Olympus Panametrics Epoch 4 Plus, Руководство пользователя

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Calibrating the EPOCH 4PLUS
Part # 910-250C 61
Figure 24 Calibrating for a Thick Block Using a Delay Line Transducer
8. Press [VEL] once the reading is steady. The screen freezes and a pop-up box appears
again on the screen.
Use the alphanumeric keypad to enter the exact known thickness of the test sample.
For this example, press [5], [0], [0]. The entry appears in the pop-up box.
If you enter an incorrect number, press [0] multiple times to clear the entry and then
type the correct thickness.
Figure 25 Entering a Thick Standard Value
9. Press [ENTER] to complete the Auto-Calibration. The Zero Offset and Velocity
parameters adjust automatically, and the correct thickness reading of any gated echo is
displayed on the screen.
Note: It is possible to use Auto-Calibration on a single test block of known
thickness. You can use multiple backwall echoes instead of coupling on both
a thin step and a thick step. You can leave the transducer coupled on the thin
step, and instead move the gate over to one of the multiple backwall echoes
and enter the correct soundpath thickness (2, 3, 4, etc. multiple of the first
backwall echo) during the velocity portion of the calibration.
7.4 Calibrating with a Dual Element Transducer
The sample delay line calibration described below is performed using Olympus NDT
TM
transducer part number DHC711-RM, with a frequency of 5.0 MHz and an element