🔍 Key Concepts

• SITOR (NBDP) automatic TELEX formatters used to route messages to specific authorities • The role of the OBS+ command in identifying certain types of reports (e.g. observational messages) • How additional commands (like WX+, MSG+, or GA+?) modify or clarify the purpose and routing of the message

💭 Think About

• Ask yourself: which command is specifically associated with observational reports (such as weather observations) rather than general message headers? • Consider whether the national weather authority needs a single, standard identifier to automatically recognize incoming ship weather reports, or a sequence of different identifiers. • Think about what GA+? normally does in TELEX procedures: does it relate to turn‑taking in a conversation, or to addressing a report to a specific authority?

✅ Before You Answer

• Verify which automatic command is explicitly linked to ship’s weather observations in your GMDSS/NBDP reference materials. • Confirm whether WX+ is an internationally standardized NBDP address command or just an intuitive abbreviation. • Check if combining multiple prefixes (e.g., OBS+ then MSG+) is part of the standard procedure, or if the regulations describe using one specific automatic command for this situation.