Horizontal Linearity

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```					                            Assessment of Horizontal Linearity

UT Model                                                                Date

UT Serial #                                                             Technician

Probe Model                                                                Probe Frequency

Probe Serial #                                                                     Range

Theoretical      Actual
BWE                                % Error     Comply < 1%
Position       Position
1                                 #DIV/0!        #DIV/0!
2                                 #DIV/0!        #DIV/0!
3                                 #DIV/0!        #DIV/0!
4                                 #DIV/0!        #DIV/0!
5                                 #DIV/0!        #DIV/0!

1.0
Theoretical
0.9                        Actual

0.8

0.7

0.6
Theoretical

0.5

0.4

0.3

0.2

0.1

0.0
0.0         0.2              0.4            0.6                 0.8                1.0                1.2
Actual

Procedure
(a) For ranges up to 100 mm.
Use Step Wedge or V1 Block
Place the probe on the block and adjust the time base so as to produce several multiple echoes within the chosen range, the
preferred number being 4 or 5 echoes.
(b) Setting the time base.
Two of the repeat echo signals shall be set to coincide with appropriate scale divisions, e.g. in a 5-echo display choose the 1st
and the 4th echoes, and in a 4-echo display choose the 1st and 3rd echoes. The remaining echoes should then coincide with
their assigned positions.
(ie: if using 20mm step, Echo 1 should read 20mm and echo 4 should read 80mm)
(c) Setting the gain.
Successive echoes should be brought to the same amplitude, i.e. 80 percent of full screen height when measuring their position
against the graticule.
(d) Recording and plotting of results.
Record the actual echo position on the screen and theoretical position is above table.

For Personal Training Use Only

Created by: P.Grosser
Assessment of Vertical Linearity

UT Model                                                                Date

UT Serial #                                                          Technician

Probe Model                                                      Probe Frequency

Probe Serial #

Hn           H(n+1)    Hn / H(n+1)                        AB
#DIV/0!                           X Y
#DIV/0!                            0 #DIV/0!
#DIV/0!                           ## #DIV/0!
#DIV/0!
#DIV/0!                           -2 dB      +2 dB
#DIV/0!                           y x        y                         x
#DIV/0!                            0 #DIV/0!       0                    #DIV/0!
#DIV/0!                           ## #DIV/0!     100                    #DIV/0!
#DIV/0!                            0 #DIV/0!       0                    #DIV/0!
#DIV/0!                         ## #DIV/0!     100                    #DIV/0!
100

90

80
Data
70

60                                                                                                              AB
Hn

50                                                                                                              -2 dB

40                                                                                                              +2 dB

30
-0.5dB
20
+0.5dB
10

0
0.80      0.90       1.00        1.10        1.20        1.30         1.40        1.50        1.60
Hn / H(n+1)

Procedure
(a) Turn all accessible suppression and/or swept gain controls to the ‘off’ position.
(b) Select a test range of approximately 250 mm and place the probe on 25mm thickness.
(c) Select a back echo (the nth echo) which is adjacent to the centre of the screen and adjust the gain so that its height (h n)
is 10 percent of graticule height.
(d) Measure and record the height of the next succeeding back echo (h(n + 1)). Repeat this procedure, adjusting the gain
so that hn is increased by 10 percent of graticule height.

For Personal Training Use Only

Created by: P.Grosser

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