Ham Radio General Class Test Digital Modes and Data Communications 3

Question 1

What is DMR in the context of amateur radio communication?

Accepted Answer

A Time Division Multiple Access digital voice mode used on VHF and UHF

Answer

A weak-signal data mode designed for HF propagation testing

Answer

A type of antenna matching network used with digital transceivers

Answer

A method of measuring radio frequency output power digitally

Question 2

What is Varicode, as used by PSK31?

Accepted Answer

A variable-length character encoding that assigns shorter codes to more frequently used characters

Answer

A fixed-length 7-bit binary code that is compatible with standard ASCII

Answer

A special error-correcting code designed for weak-signal HF conditions

Answer

An encoding method that uses varying frequency shifts for each character transmitted

Question 3

With which digital communication system is D-STAR primarily associated?

Accepted Answer

Digital voice and data linked through repeater networks and the internet

Answer

Satellite orbit determination for amateur radio satellites

Answer

Meteor scatter digital communication on VHF bands

Answer

Automatic HF propagation beacon reporting to an internet database

Question 4

What is the standard baud rate used for Baudot RTTY on HF amateur radio bands?

Accepted Answer

45.45 baud

Answer

300 baud

Answer

1200 baud

Answer

9600 baud

Question 5

Which of the following best describes the FT4 digital mode?

Accepted Answer

A faster variant of FT8 using 7.5-second cycles designed for contest operation

Answer

A mode used exclusively for satellite uplink communications

Answer

A 4-tone FSK mode designed for EME operation on VHF bands

Answer

A slow-speed mode optimized for NVIS HF propagation paths

Question 6

What is the primary advantage of digital modes such as FT8 over SSB voice for weak-signal communication?

Accepted Answer

Digital modes can successfully decode signals 15 dB or more below the audible noise floor

Answer

Digital modes always occupy significantly less bandwidth than SSB voice signals

Answer

Digital modes allow higher legal transmitter power output on HF bands

Answer

Digital modes do not require an amateur radio license to operate on HF

Question 7

What emission type designator applies to RTTY that uses direct frequency shift keying of the carrier?

Accepted Answer

F1B

Answer

J3E

Answer

A1A

Answer

F3E