Important Radar Tester Interview Preparation Guide

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The term Duty factor is the amount of time radar transmits compare to listening time. It is often expressed in percent. It is calculated by multiplying PRF and pulse width OR
by dividing pulse width with PRT

Vibration sensors are sensors for measuring, displaying, and analyzing linear velocity, displacement and proximity, or acceleration. Vibration — however subtle and unnoticed by human senses — is a telltale sign of machine condition.

The vibration velocity, acceleration, and expansion in a frequency range of 10 Hz to 1 kHz can be measured. The cables of the vibration sensors are 1.2 m long, so the vibration measuring device is able to record vibrations at different points of the component to be tested.

Vibration Analysis (VA), applied in an industrial or maintenance environment aims to reduce maintenance costs and equipment downtime by detecting equipment faults. VA is a key component of a Condition Monitoring (CM) program, and is often referred to as Predictive Maintenance (PdM).

All these are units of power measurement , dBm refers to decibel related to 1 milliwatt, dBW refers to decibel related to 1 watt

The term bandwidth is the frequency difference between upper frequency and lower frequency on EM spectrum radiation. It is expressed in Hz.

Many people question whether there is any danger for the person using GPR equipment, and the answer is no. Although “ground penetrating radar” may sound like a hazardous technique, it is extremely safe and emits roughly 1% of the power of a cellular phone signal.

A wide variety of cracks, voids, disbonds, inclusions, and similar problems that affect structural integrity can all be located and measured with ultrasonic flaw detectors. The minimum detectable flaw size in a given application will depend on the type of material being tested and the type of flaw under consideration.

First-time users will need 2-3 days of training to become familiar with the equipment and ground penetrating radar theory. Training is provided free of charge with most GSSI equipment.

In industrial applications, ultrasonic testing is widely used on metals, plastics, composites, and ceramics. The only common engineering materials that are not suitable for ultrasonic testing with conventional equipment are wood and paper products. Ultrasonic technology is also widely used in the biomedical field for diagnostic imaging and medical research.

The term Pulse Width is time interval between leading and trailing edge of a pulse at a point where their amplitudes are 50% of the max. values. The unit is microseconds.

Resonance is the result of an external force vibrating at the same frequency as the natural frequency of a system. Natural frequency is a characteristic of every machine, structure and even animals. Often, resonance can be confused with the natural frequency or critical frequency.

A transducer is any device that converts one form of energy into another. An ultrasonic transducer converts electrical energy into mechanical vibrations (sound waves), and sound waves into electrical energy. Typically, they are small, hand-held assemblies that come in a wide variety of frequencies and style to accommodate specific test needs.

C/I refer to ratio of carrier power to the interference power. SNR refer to ratio of signal power to the noise power. C/I apply to modulated waveform while SNR applies to the unmodulated waveform

Ultrasonic nondestructive testing, also known as ultrasonic NDT or simply UT, is a method of characterizing the thickness or internal structure of a test piece through the use of high frequency sound waves. The frequencies, or pitch, used for ultrasonic testing are many times higher than the limit of human hearing, most commonly in the range from 500 KHz to 20 MHz.

A vibrometer is generally a two beam laser interferometer that measures the frequency (or phase) difference between an internal reference beam and a test beam. The most common type of laser in an LDV is the helium–neon laser, although laser diodes, fiber lasers, and Nd:YAG lasers are also used.

monostatic radar is a radar which uses common antenna for transmission as well as reception OR uses two adjacent antennas for the same. Doppler weather radars are of this type.

Yes. GPR is the best geophysical technique for forensic victim location and for the mapping of graves in cemeteries. While we can sometimes image the body directly, GPR responds well to the disturbances in the soil which are created when a pit is dug and refilled.

Ultrasonic flaw detectors are widely used in critical safety-related and quality-related applications involving structural welds, steel beams, forgings, pipelines and tanks, aircraft engines and frames, automobile frames, railroad rails, power turbines and other heavy machinery, ship hulls, castings, and many other important applications.

RF circulator is a 3 port device and isolator is a 2 port device. Both allow signal to flow in any one direction and prevents signal going into the other direction as per design. RF circulator being having 3 ports, there are two main types clockwise and anticlockwise. If ports are say P1, P2 and P3 then isolator can pass signal from P1 to P2, P2 to P3 and from P3 to P1 and not in other direction if designed so otherwise it will pass signal from P3 to P2 and P2 to P1 and from P1 to P3.

A major use for ultrasonic gages is the measurement of remaining wall thickness in corroded pipes and tanks. The measurement can be made quickly and easily without needing access to the inside or requiring the pipe or tank to be emptied. Other important applications include measuring the thickness of molded plastic bottles and similar containers, turbine blades and other precision machined or cast parts, small diameter medical tubing, rubber tires and conveyor belts, fiberglass boat hulls, and even contact lenses.

RADAN is GSSI’s ground penetrating radar processing software. It has been developed over the last 20 years to aid in the processing and interpretation of GPR data. It will run on a regular laptop or desktop computer and provides the user with many powerful tools to clean up data and view data in 3D.& RADAN is an acronym that stands for RAdar Data ANalyzer.

GPR systems work by sending a tiny pulse of energy into a material via an antenna. An integrated computer records the strength and time required for the return of any reflected signals. Subsurface variations will create reflections that are picked up by the system and stored on digital media. These reflections are produced by a variety of material such as geological structure differences and man-made objects like pipes and wire.

Ultrasonic testing is completely nondestructive. The test piece does not have to be cut, sectioned, or exposed to damaging chemicals. Access to only one side is required, unlike measurement with mechanical thickness tools like calipers and micrometers. There are no potential health hazards associated with ultrasonic testing, unlike radiography. When a test has been properly set up, results are highly repeatable and reliable.

Have you ever faced personal questions like tell me about your girlfriend or when are you planning to have kids or do you drink alcohol? Probes like these are considered inappropriate and unprofessional but prevalent amongst lazy interviewers who believe them to be a proxy of commitment to a job.

You may not face these in international roles where such questions may be illegal under local laws. You can refuse to answer with a polite “I prefer not to discuss my private life”. However, you can also choose responses like “I am presently focused on building my career and have no current family commitments”, or “I am aware of company policies regarding smoking and I respect them”.