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ISO/IEC 15693, is an ISO/IEC standard for vicinity cards, i.e. cards which can be read from a greater distance as compared with proximity cards.Such cards can normally be read out by a reader without being powered themselves, as the reader will supply the necessary power to the card over the air (wireless).
One of the most basic forms of frequency meter is the vibrating reed meter or tuned reed meter. This consists of an electromagnet coil carrying the signal positioned near the end of a tuned metal reed or tuning fork-type arrangement. As the signal travels through the coil it creates a magnetic field with the sample frequency, which pushes and ...
A frequency counter is an electronic instrument, or component of one, that is used for measuring frequency. Frequency counters usually measure the number of cycles of oscillation or pulses per second in a periodic electronic signal. Such an instrument is sometimes called a cymometer, particularly one of Chinese manufacture. [citation needed]
A via fence consists of a row of via holes, that is, holes that pass through the substrate and are metallised on the inside to connect to pads on the top and bottom of the substrate. In a stripline format both the top and bottom of the dielectric sheet are covered with a metal ground plane so any via holes are automatically grounded at both ends.
The pulse-repetition frequency (PRF) is the number of pulses of a repeating signal in a specific time unit. The term is used within a number of technical disciplines, notably radar. In radar, a radio signal of a particular carrier frequency is turned on and off; the term "frequency" refers to the carrier, while the PRF refers to the number of ...
A cover meter is an instrument to locate rebars and measure the exact concrete cover. Rebar detectors are less sophisticated devices that can only locate metallic objects below the surface. Due to the cost-effective design, the pulse-induction method is one of the most commonly used solutions. [1]
Hall effect magnetometers (also called tesla meters or gauss meters) use a Hall probe [23] with a Hall element to measure magnetic fields or inspect materials (such as tubing or pipelines) using the principles of magnetic flux leakage. A Hall probe is a device that uses a calibrated Hall effect sensor to directly measure the strength of a ...
Invisible Fence Inc. (commonly referred to as Invisible Fence Brand) is a company that designs radio pet fences for cats and dogs. Manufactured and distributed by Radio System Corporation, the company sells wireless and fenceless systems that were first introduced in 1973. [ 1 ]