RYA SRC VHF Channel Usage 3

Question 1

What is the transmission power for most ship-to-shore communications?

Accepted Answer

High power (25 watts) for long range communications

Answer

High power (25 watts) should be used for ship-to-shore communications to ensure reliable contact. Low power (1 watt) is used for short-range communications to reduce interference with distant stations.

Question 2

What is the typical VHF radio range at sea?

Accepted Answer

20-30 miles depending on antenna height

Answer

VHF radio has line-of-sight range typically 20-30 miles between vessels and up to 40 miles to shore stations on high ground. Antenna height significantly affects range as VHF cannot propagate beyond the horizon.

Question 3

Which power setting should be used for close-range marina communications?

Accepted Answer

Low power (1 watt)

Answer

Low power (1 watt) should be used for short-range communications such as marina approaches to reduce interference with other stations using the same channel at greater distances.

Question 4

What is a 'working channel' in VHF radio procedure?

Accepted Answer

Any channel other than Channel 16 used for the main body of communication

Answer

A working channel is any agreed VHF channel (other than the calling/distress channels) on which the substantive communication takes place after initial contact has been made on Channel 16 or via DSC.

Question 5

Can Channel 16 be used for routine ship-to-ship conversation?

Accepted Answer

No, it must only be used for distress, safety, calling, and essential navigation

Answer

Channel 16 must not be used for routine conversation. Its sole purpose is distress and safety traffic, calling (to establish contact), and essential navigational communications. All other traffic must move to a working channel.

RYA SRC Practice Test

RYA SRC Practice Test

RYA SRC VHF Channel Usage 3