Owner manual

Dakota Ultrasonics
74
Where:
N = Near Field Length
DEFF = Effective Diameter
= Wave Length (velocity/frequency)
In order to approximate the effective diameter, the shape of the crystal must be taken
into account. Transducers are either round or square/rectangular in shape, and can
be approximated as follows:
Round Crystal (DEFF)
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Where:
DEFF = Effective Diameter
Dia. = Diameter of the crystal
0.97 = Fixed ratio
Square/Rectangle (DEFF)
Where:
K = Aspect Ratio
A = Largest Dimension
B = Smallest Dimension
Where: