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EMAT-VG System
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System Features
The Electro-Magnetic Acoustic Transducer
(EMAT) system is a computer controlled multi-system used to operate EMAT transducers for couplant-free transmitting
and receiving of oblique incident bulk ultrasonic waves and guided
waves in ferromagnetic materials using conventional ultrasonic
instruments.
The system serves as signal-generating and processing
(frequency filtering and gain control) component.
It
provides time delayed RF signals for transmitter stages,
amplification, filtering and summation of the received signals and
power supply of the electromagnets of the transducers.
System control, such as frequency, pulse length
(number of cycles), transducer selection, etc., is
performed by the associated UT system. |
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System Characteristics |
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Base Unit
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Synthesizer board
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Burst generator
board; burst length (number of
cycles) and frequency are adjustable in the system settings
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Single board with a maximum of eight transmitter power stages
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Up to eight parallel transmitter/receiver channels with
Phased Array capability
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Receiver board with four selectable band filters and four
amplifier stages
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Control PC for system control and parameter settings via
USB; settings data are saved to the EMAT-VG and the Control PC can
be disconnected during data acquisition
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Signals received from the receiver coils are pre-amplified in the
transducer by built-in preamplifiers and transmitted to the
system; there, the signals are further amplified and filtered by the
filter stages.
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Technical Data |
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Frequency Range:
Burst Duration:
Pulse Repetition Rate:
Amplification:
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50kHz - 10MHz
1 - 15 cycles,
adjustable in steps of 1
400Hz, depending on transducer in use
0dB, 13dB, 26dB and 40dB
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Computer Controlled Parameters
and Functions |
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Block
Diagram |
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