Which of the following would be a valid...

Question 1 / 27070TzevpZ8Geo49ygcyHkXw

Question 1 of 27070TzevpZ8Geo49ygcyHkXw

Which of the following would be a valid SELCAL for use in ARQ communications?

Question 1 of 27070

Which of the following would be a valid SELCAL for use in ARQ communications?

🔍 Key Concepts

• SELCAL (selective calling) use in ARQ (Automatic Repeat reQuest) radioteletype/telex systems • The typical format and length of a SELCAL code used in maritime telex/ARQ services • Difference between a numeric SELCAL code, a plain-language call sign/text, and a binary data pattern

💭 Think About

• Look at each option and ask: which one looks like an actual selective calling code that a coast station could assign, rather than a description or a data pattern? • Consider what an operator would practically enter or recognize on a maritime telex/ARQ terminal when calling a specific ship. • Decide which choices are descriptions or explanations about how the system works, versus an actual example of a SELCAL in the correct format.

✅ Before You Answer

• Check which option is a simple, specific code that could realistically be printed in a list of ship telex SELCALs. • Eliminate any choices that are not in a realistic SELCAL format (too long, includes words, or just describes binary). • Verify that the remaining option is something you could directly dial or key in as a selective calling code in ARQ communications.

Question 1 of 27070

Which of the following would be a valid SELCAL for use in ARQ communications?

1106

212420 WHAQ X.

Four marks (ones) and three spaces (zeroes) forming the binary signal "1001101".

This is established by the communications protocol used with the modem.

Question 1 / 27070TzevpZ8Geo49ygcyHkXw

Question 1 of 27070TzevpZ8Geo49ygcyHkXw

Which of the following would be a valid SELCAL for use in ARQ communications?

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Question 1 of 27070

Which of the following would be a valid SELCAL for use in ARQ communications?