HAM HAM Radio Extra Class Test Practical Electronics Circuits Questions and Answers 2

Question 1

What is the primary purpose of a bleeder resistor in a power supply circuit?

Accepted Answer

To discharge filter capacitors when the supply is turned off

Answer

A bleeder resistor safely discharges stored energy in filter capacitors after the power supply is switched off, preventing electrical shock.

Question 2

In a Class AB amplifier, what advantage does it offer over a Class B amplifier?

Accepted Answer

Reduced crossover distortion

Answer

Class AB biases both transistors slightly into conduction, eliminating the dead zone at the crossover point that causes distortion in Class B designs.

Question 3

What is the function of a bypass capacitor placed across the emitter resistor in a common-emitter amplifier?

Accepted Answer

To increase AC voltage gain by shorting the emitter resistor at signal frequencies

Answer

The bypass capacitor provides a low-impedance path for AC signals around the emitter resistor, removing the negative feedback that reduces gain at signal frequencies.

Question 4

Which component in a voltage regulator circuit provides the reference voltage for comparison?

Accepted Answer

A zener diode

Answer

A zener diode maintains a stable reference voltage across its terminals when reverse-biased, which the regulator compares against the output to maintain regulation.

Question 5

What happens to the Q factor of a parallel resonant circuit if the resistance in the circuit increases?

Accepted Answer

The Q factor decreases

Answer

Q factor equals the ratio of reactive power to resistive power, so increasing resistance raises losses and reduces the circuit's Q factor.

HAM - Radio Extra Class Test Practice Test

HAM - Radio Extra Class Test Practice Test

HAM HAM Radio Extra Class Test Practical Electronics Circuits Questions and Answers 2