12/03/2015 Untitled Document

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Working of Electro­magnetic EDM Instrument

Electromagnetic (microwaves) EDM instrument transmit high­frequency microwave. The measurement involves twointerchangeable instruments, one being set up on each end of the line to be measured. The sending instrumenttransmits a series of microwaves which run through the circuitry of the receiving unit and are retransmitted to the originalsending unit, which measures the phase difference between the transmitted and received signal. The net phasedifference gets converted to linear distance.

In this case the inter visibility between stations is not required; however, an unobstructed measured path betweenstations is necessary.

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