HAM Practice Questions 3

Question 1

What does the term 'third-order intercept point' (IP3) indicate about an RF amplifier?

Accepted Answer

A measure of the amplifier's linearity and resistance to intermodulation distortion

Answer

IP3 is a theoretical extrapolation that quantifies an amplifier's linearity; a higher IP3 means less intermodulation distortion at a given input power.

Question 2

Which digital mode was specifically designed for weak-signal meteor-scatter and EME communication?

Accepted Answer

JT65

Answer

JT65, developed by Joe Taylor K1JT, was designed for extremely weak signals and is widely used for EME (moon-bounce) and weak-signal VHF/UHF work.

Question 3

What is the relationship between skin depth and frequency in a conductor?

Accepted Answer

Skin depth decreases as frequency increases

Answer

Skin depth decreases as frequency increases because the skin effect forces current to flow closer to the conductor's surface at higher frequencies.

Question 4

What is the function of a 'noise blanker' in a receiver?

Accepted Answer

To detect and suppress short-duration impulse noise pulses

Answer

A noise blanker samples the incoming signal, detects impulse noise spikes (such as ignition noise), and briefly mutes the receiver during each pulse.

Question 5

When operating through a satellite repeater, why must operators use the minimum power necessary?

Accepted Answer

Excessive power desensitizes the satellite's receiver and degrades the link for others

Answer

Satellite linear transponders are shared resources; using excess power captures more of the transponder's dynamic range and causes AGC-driven gain reduction that affects all other users.

HAM - Radio Extra Class Test Practice Test

HAM - Radio Extra Class Test Practice Test

HAM Practice Questions 3