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All questions
Marine radio

What is the defining operating rule for Channel 70?

Short answer

It carries DSC digital signalling and must not be used for speech

Channel 70 carries the DSC alert or selective call. The required voice traffic follows on Channel 16 or an accepted working channel according to the priority and procedure.

Sources and scope

Reviewed by Richard Moore on . This answer is scoped to united kingdom marine vhf and internationally harmonised procedure; check the current chart, publication, local rules and official operational guidance before acting afloat.

Quick check

What is the defining operating rule for Channel 70?