What is the maximum authorized bandwidth of...

Question 1 / 270709iOMRwbVhpocSTQik4Bg

Question 1 of 270709iOMRwbVhpocSTQik4Bg

What is the maximum authorized bandwidth of a high frequency radiotelegraphy signal, emission A1A, in the maritime service?

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Question 1 of 27070

What is the maximum authorized bandwidth of a high frequency radiotelegraphy signal, emission A1A, in the maritime service?

🔍 Key Concepts

• HF radiotelegraphy (A1A) emission and what A1A means • ITU/US maritime rules that set numerical bandwidth limits for different emission types • Difference between a fixed maximum bandwidth and a vague "minimum necessary" requirement

💭 Think About

• Look up the specific numeric bandwidth limit for A1A emissions in the maritime HF bands: is it given as a fixed kHz value or only as a general principle? • Compare the typical bandwidths used for narrow-band telegraphy (Morse) with voice SSB and CW to see which option is realistic for HF telegraphy. • Ask yourself: in regulations, when a maximum is specified, do they usually phrase it as a number or as "minimum necessary"?

✅ Before You Answer

• Confirm the definition of A1A (narrow-band, on-off keyed telegraphy) and its usual occupied bandwidth. • Check in the relevant ITU-R and national regulations for the exact numeric maximum authorized bandwidth for HF A1A in the maritime service. • Verify whether "minimum necessary" is used as a general principle or as a replacement for a specific numeric limit in HF telegraphy rules.

Question 1 of 27070

What is the maximum authorized bandwidth of a high frequency radiotelegraphy signal, emission A1A, in the maritime service?

0.4 kHz

0.2 kHz

Minimum necessary to complete necessary communications

1 kHz

Question 1 / 270709iOMRwbVhpocSTQik4Bg

Question 1 of 270709iOMRwbVhpocSTQik4Bg

What is the maximum authorized bandwidth of a high frequency radiotelegraphy signal, emission A1A, in the maritime service?

Back

Question 1 of 27070

What is the maximum authorized bandwidth of a high frequency radiotelegraphy signal, emission A1A, in the maritime service?