Frequency Of Channels - mcmurdo R2 GMDSS Owner's Manual

3.4 Frequency of Channels

R2 GMDSS models are fitted with simplex channels only.
Channel 70 is restricted for DSC (Digital Selective Calling) use only and is therefore not available on the
R2 Professional or GMDSS VHF radio.
Channel 0 will only be made available in the UK to Coastguard users with written authorisation.
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