User's Manual

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Appendices | RS90 Operating Manual
Appendix 8 - DSC information
Class D equipment, which is specifically designed for recreational
vessels, provides VHF DSC distress, urgency and safety as well as
routine calling and position polling. Class D equipment includes a
dedicated channel 70 DSC receiver, so you will never miss a DSC call.
Position polling refers to requesting the position of another vessel at
regular intervals.
Appendix 9 - AIS information
There are several types of AIS device as follows:
Class A transceivers
Class A transceivers are similar to class B transceivers, but they are
designed to be fitted on large vessels such as cargo ships and large
passenger vessels. Class A transceivers transmit at a higher VHF
signal power than class B transceivers and therefore can be received
by more distant vessels, and also transmit more frequently. Class A
transceivers are mandatory on all vessels over 300 gross tonnes on
international voyages and certain types of passenger vessels under
the international Safety of Life at Sea (SOLAS) regulations.
Class B transceivers
Similar to class A transceivers in many ways, but are normally lower
cost due to the less stringent performance requirements. Class B
transceivers transmit at a lower power and at a lower reporting rate
than class A transceivers.
AIS transceivers
AIS transceivers are used by Vessel Traffic Systems to monitor and
control the transmissions of AIS transceivers.
Aids to Navigation (AtoN) transceivers.
AtoN transceivers are mounted on buoys or other hazards to
shipping in order to transmit details of their location to the
surrounding vessels.
The RS90 VHF radio includes an AIS receiver-only function.
Draft v5.0
27 Feb 2014