Ultrasonic waves experiment system of reflexion
Objects
Demonstrating the principle of an echo sounder.
Determining the velocity of sound in air from the transit time of a sound pulse and the distance to the reflecting object.
Determining distance by measuring the transit time of the sound pulse.
Principles
Ultrasonic waves are reflected at the boundary surfaces between media with differing resistances to sound waves. An echo sounder (or sonar)device emits pulsed ultrasonic signals and measures the time in which a signal is reflected from such a boundary surface to the receiver. To simplify the configuration, the transmitter and receiver are in the same location.
The time between transmission and reception can be used to determine the distance to the reflecting object (if the velocity of sound is known), or to determine the velocity of sound over a known distance. This method is commonly used e.g. to determine water depths at sea.
In the experiment, the echo-sounder principle is used to determine the velocity of sound in air, and to determine distances.
Two ultrasonic transducers serve as the transmitter and receiver, depending on their connection.
A piezoelectric body converts electrical to mechanical energy. When the AC voltage is applied to the piezoelectric body, the transducer configured as a transmitter supplies a sufficiently high sound amplitude at a resonance frequencies (approx. 40 kHz). Conversely, sound waves generate mechanical oscillations in the transducer when configured as a receiver. The amplitude of the resulting piezoelectric AC voltage is proportional to the sonic amplitude.
 | System composition |
2 pcs
1 pc
1 pc
1 pc
2 pcs
2 pcs
1 pc
1 pc | Ultrasonic transducers 40 kHz
AC amplifier
Generator 40 kHz
Digital storage oscilloscope
Test leads
Stand base, V-shape
Metal scale, 1 m
Reflection plate | P416000
F16-015
F16-014
DQ7202CA
PTL927
P101413
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F16-014 Generator 40 kHz
Features
With continuance and spacing square wave generator for operating source, for ultrasonic transducer 40 kHz (P416000) as an emitter. Inner and
external frequency counter
Technical Data
Generator
Frequency range: 40 kHz, can be set from 35 kHz to 50 kHz
Pulse operation:
pulse duration approx. 0.2 ms
pulse spacing approx. 80 ms
Transducer output voltage: ＞18 Vpp
Trigger output voltage: ＞9 Vpp
Counter Frequency range: 1KHz~150kHz
Sensitivity: 100mV
Max. input voltage: 20V
Connection sockets: 4 mm dia.
Dimensions: 19 cm × 13.5 cm × 7 cm
Weight: 0.5kg
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 | F16-015 AC-amplifier
Features
Sensitive amplifier with microphone input for verifying ultrasonic waves in
conjunction with an ultrasonic transducer (P416000) as a receiver, and sound
amplification
Technical Data
Gain: 10× to 1000×, continuously adjustable
Frequency range: 10 kHz (100Hz microphone input) to 50 kHz
Outputs: signal, trigger and level, short-circuit proof
Max. signal output: 4 Vp-p
Trigger output: TTL compatible
Max. DC level output: 4 V
Connection sockets: 4 mm dia.
Dimensions: 19 cm × 13.5 cm × 7 cm
Weight: 0.5kg |
P416000 Ultrasonic transducer 40 kHz
Features
Piezoelectric air ultrasonic transducer for experiments in the areas of
geometric and wave-mechanical acoustics. The transducer is used as
transmitter and receiver. In housing, on stand rod, with coax.
connection cable.
Technical Data
Resonance frequency: 40 kHz
Bandwidth: approx. 6 kHz
Capacitance: 2000 pF
Connection: 1 m coax. cable with 4 mm sockets
Housing: 48 mm × 27 mm dia.
Stand rod: 20 cm × 10 mm dia. | 
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