HAM FREE Ham Radio Extra Class General Questions and Answers 3

Question 1

What is the approximate noise figure of a well-designed preamplifier used for weak-signal VHF work?

Accepted Answer

0.5 dB

Answer

A high-quality VHF preamplifier for weak-signal work typically achieves a noise figure of about 0.5 dB or less.

Question 2

Which type of filter has the steepest skirt selectivity for a given number of poles?

Accepted Answer

Chebyshev

Answer

Chebyshev filters provide the steepest rolloff for a given filter order, at the expense of passband ripple.

Question 3

What is the purpose of interleaving in digital communication modes used by amateur operators?

Accepted Answer

To spread burst errors across multiple data blocks so error correction can recover the data

Answer

Interleaving redistributes data so that burst errors affect different code blocks, allowing forward error correction to recover the original data.

Question 4

What is the third-order intercept point (IP3) of a receiver used to measure?

Accepted Answer

The receiver's ability to handle strong signals without generating intermodulation distortion

Answer

The third-order intercept point indicates how well a receiver resists producing intermodulation products from strong nearby signals.

Question 5

Under FCC Part 97, what is the maximum transmitter power level permitted on the 60-meter band for Amateur Extra licensees?

Accepted Answer

100 watts ERP

Answer

The 60-meter band (5 MHz) is limited to 100 watts ERP relative to a half-wave dipole for all amateur licensees.

HAM - Radio Extra Class Test Practice Test