Olympus Sonic 1200S/HR, Руководство пользователя

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Applications 103
Figure 5-39: B1 Block Echoes
All figures represent a 10 inch screen range.
9. When the echoes are lined up at both points, the horizontal sweep is calibrated.
Measurement of the wedge angle by use of a IIW Test Block:
10. If the index point of the wedge is not known exactly, it is first necessary to determine it.
To find the true index point on the wedge:
11. Place the transducer with couplant on the block to reflect from the large 4 inch radius end
(as shown in Figure 5-40).
12. Move the transducer to maximize the echo. The true index point will be directly at the
center index mark. If this is different from the marking on the wedge, re-mark the index.
13. Now, check the wedge refraction angle by the following procedure: a) for IIW Block
Types 1 and 2, and b) for the B1 Block.