A DSC Distress call is received by your vessel and your transceiver frequency display reads: Transmit = 4207.5 kHz and Receive = 4207.5 kHz -- what information can you infer from this?

Correct Answer: Option D — The DSC call came in on 4 MHz DSC. You should set-up your transmitter and respond on the appropriate voice follow-on frequency.

DSC distress alerts on MF/HF utilize dedicated calling frequencies, such as 4207.5 kHz. Per IMO GMDSS standards, the DSC controller identifies the distress frequency, but the operator must manually tune the transceiver to the designated radiotelephony follow-on frequency for voice communication, as DSC controllers do not automatically switch to voice channels.