Login or Register for FREE!
Login or Register for FREE!
Subel. J
6 questions
Subelement J

MF-HF Equip. and Comms:

Section 82

MF-HF ITU Channels

Which of the following defines "ITU Channel 1216"?

  • Ch-12 in the 16 MHz band.
  • Ch-1216 in the MF band.
  • Ch-12 in the 16 kHz band.
  • Correct Answer
    Ch-16 in the 12 MHz band.

12 MHz Duplex Channels
Their correct answer is D Ch-16 in the 12 MHz band. So to get the point for the correct answer, D is the one.

But if you look at the US Coast Guard table for this question, it is kHz, and not MHz. Below is from their table:

ITU Channel Number of 1216 uses coast transmit 13.122kHz and ship transmit of 12.275 kHz.

For more details, please see
US Coast Guard 12 MHz Duplex Channels

Last edited by markadlerdallas. Register to edit

Tags: none

Which of the following is a valid 22-MHz ITU Channel?

  • Correct Answer
    HF Ch-2206
  • VHF Ch-22
  • Ch-22A VTS
  • Ch-70 (DSC only)

22 MHz Duplex Channels

ITU Channel No.       2206
Coast Transmit   kHz   22.711
Ship Transmit   kHz   22.015

For more details and a table of frequencies please see US Coast Guard 22 MHz Duplex Channels

Last edited by markadlerdallas. Register to edit

Tags: none

What is meant by the term duplex "ITU channel"?

  • This refers to a vessel's SELCAL number.
  • Correct Answer
    A standardized series of frequency pairings for common use.
  • This refers to VHF channels 1-28 and 60-88.
  • A series of frequency pairings used for ship-ship communications.

(B). A standardized series of frequency pairings for common use.

It is the listing of the VHF channels 1-28 and 60-88, combining a series of frequency pairings to be used for ship-ship communications.

A practical description of the ITU channels can be found on 3Copits web site: Understanding ITU Channels

Last edited by markadlerdallas. Register to edit

Tags: none

ITU duplex channel 1604 would mean:

  • Ch-16 in the 4 MHz band.
  • Ch-1604 in the MF band.
  • Correct Answer
    Ch-4 in the 16 MHz band.
  • Ch-4 in the 6 MHz band.

(C). Ch-4 in the 16 MHz band.

ITU Channel No.       1604
Coast Transmit   kHz   17.251
Ship Transmit   kHz   16.369

For US Coast Guard table regarding ITU duplex 1604, see 16 MHz Duplex Channels

Last edited by markadlerdallas. Register to edit

Tags: none

What is a potential danger of using the manufacturer’s database to set up for operations using MF-HF ITU frequency assignments?

  • All manufacturer’s frequency databases are required to be standardized & accurate so that there is no danger.
  • Using the manufacturer’s frequency database to setup the transceiver typically takes longer and is more prone to error than a manual setup.
  • Correct Answer
    Different manufacturers use different database numbering systems to incorporate the ITU assignments into the transceiver and therefore a potential for confusion exists.
  • Using the manufacturer’s frequency databases ensures that the transceiver is always restricted to the vessel’s licensed frequencies so that there is no danger.

(C). Different manufacturers use different database numbering systems to incorporate the ITU assignments into the transceiver and therefore a potential for confusion exists.

To select appropriate frequencies consult ITU and US Coast Guard guidance documents and compare with the manufacturer's listing of channels and frequencies.

ITU Website International Telecommunication Union

U.S. Coast Guard Website Coast Guard Main Page

Last edited by markadlerdallas. Register to edit

Tags: none

ITU Duplex channels are:

  • Frequency assignments specific to U.S. vessels only.
  • VHF-FM frequencies.
  • International Traffic Utility frequencies.
  • Correct Answer
    Internationally standardized assignments of frequency pairs for common use.

(D). Internationally standardized assignments
of frequency pairs for common use

The details of the pairing for various bands can be found in the ITU document, called
"Frequency arrangements for implementation of the terrestrial component of International Mobile Telecommunications (IMT) in the bands identified for IMT in the Radio Regulations." ITU-R M.1036-4

Last edited by markadlerdallas. Register to edit

Tags: none

Go to 81 Go to 83
HamStudy.org™ is copyright 2024 Signal Stuff™, All rights reserved.
View Privacy Policy    |    Get help with HamStudy.org™