Obstacle

Distance

(cm)

Vp-p (mV)

w/o obstacle

Vp-p (mV)

with obstacle

Knife

2

28

23.2

3

23.4

19.8

4

20.2

16.6

4.4

19.2

13

Metal Bar

2

28

21

3

23.4

17

4

20.2

15.8

4.4

19.2

12

Screw

2

28

25

3

23.4

20

4

20.2

18.4

5.2

18

17.9

Lead solenoid

2

28

24.5

3

23.4

20.8

4

20.2

18.8

5.2

18

17.4

Nut

2

28

23.8

3

23.4

21

4

20.2

19.2