Astra Microwave Products Engineer Trainee Interview Questions and Answers

Choose a MOSFET based on voltage, current, power dissipation, switching speed, and package type.

• Consider voltage and current requirements

• Look at power dissipation and thermal considerations

• Evaluate switching speed needed for the application

• Choose the appropriate package type for mounting and heat dissipation

• Check for additional features like built-in protection circuits

• Example: For high power applications, choose a MOS

I have designed various tooling elements and selected materials based on their properties and application requirements.

• Designed tooling elements for manufacturing processes such as injection molding, stamping, and machining

• Selected materials based on properties such as strength, durability, and heat resistance

• Considered application requirements such as cost, weight, and environmental factors

• Examples include designing i...read more

We use a combination of CNC machining and injection molding for our manufacturing process.

• CNC machining is used for precision parts

• Injection molding is used for high volume production

• We also use 3D printing for prototyping

• Our manufacturing process is constantly evolving to improve efficiency and quality

Surface finish requirement for tooling elements is critical for achieving desired product quality.

• Surface finish affects the performance of the tooling element.

• It impacts the appearance and functionality of the final product.

• Surface finish is measured in Ra (roughness average) or Rz (roughness depth).

• The required surface finish depends on the application and material being used.

• For example, a mirror finish may be requi...read more

GD&T stands for Geometric Dimensioning and Tolerancing. It is a system of symbols and rules used to specify the geometry of mechanical parts.

• GD&T is used to ensure that parts fit together correctly and function properly.

• Some common symbols used in GD&T include concentricity, perpendicularity, and flatness.

• GD&T is often used in industries such as aerospace, automotive, and manufacturing.

• It allows for more precise commun...read more

Brittle materials fail as spiral fracture surface under torsion due to their inability to deform plastically.

• Brittle materials lack ductility and are unable to deform plastically under stress

• Under torsion, the material experiences shear stress which leads to the formation of spiral fracture surfaces

• The lack of plastic deformation causes the material to fail catastrophically along these spiral paths

• Examples of brittle m...read more

Entropy is a measure of disorder or randomness in a system.

• Entropy is a thermodynamic property that quantifies the amount of energy in a physical system that is not available to do work.

• It is a measure of the number of possible arrangements of particles in a system.

• Entropy tends to increase in isolated systems over time, leading to a state of maximum disorder or equilibrium.

• An example of entropy is the melting of ice -...read more

Natural frequency can be found practically by conducting modal analysis or using specialized equipment like accelerometers.

• Conduct modal analysis by applying a force or impulse to the structure and measuring the resulting vibrations.

• Use specialized equipment like accelerometers to measure the vibrations of the structure.

• Calculate the natural frequency using the formula: f = 1 / (2π√(k/m)), where f is the natural freque...read more

Fast Fourier Transform (FFT) is an algorithm used to compute the Discrete Fourier Transform (DFT) of a sequence or signal.

• FFT is used to analyze the frequency content of a signal by decomposing it into its constituent frequencies.

• It is commonly used in signal processing, image processing, audio analysis, and many other fields.

• FFT algorithms are much faster than the naive DFT computation, making it practical for real-ti...read more

FFT is a faster algorithm for calculating DFT

• FFT is faster than DFT in terms of computation time

• FFT uses a divide-and-conquer approach to reduce the number of operations

• DFT computes all frequencies while FFT only computes the frequencies of interest

• FFT is commonly used in signal processing applications