Simrad RS40 User Manual page 21

When a short press is made on the TRI key, the radio will either
switch to DUAL or TRI watch mode depending on whether a watch
channel has been setup.
Without a watch channel the radio will go to DUAL WATCH, where
the channels 'watched' are the current channel and the priority
channel (the distress channel, CH16 for most countries).
With a watch channel selected, TRI WATCH is enabled, where the
channels 'watched' are the current channel the 'watch' channel, and
the priority channel (the distress channel, CH16 for most countries).
If the radio is set to 'Country: USA', two priority channels are watched
- Channel 9 and Channel 16.
• AIS mode:
Short press to reduce (zoom in) the scale of the AIS plotter out one
range at a time. The scales available are: 1, 2, 4, 8, 16, 32 nm.
12.
16 / 9 (Radio, handset mic and wireless handset)
Short press to change to priority channel. Press again to return to
original channel. The default Priority Channel is CH16.
For US country mode: Long press to make Channel 09 the priority
channel.
13. DISTRESS (Radio and wireless handset)
Short press to start a distress call, where the nature of distress can
be selected from a list.
Long press the distress button to initiate an 'undesignated' distress
call.
The Distress call is broadcast to all DSC equipped radios, so will
create an alarm on every DSC radio within range.
If position information is available it will be included in the
transmition.
14. H/L (Transmission power) (Handset mic only)
Press to toggle between high (25 W) or low (1 W) transmission
power for the entire channel bank. The HI or LO selection is shown
on the LCD.
Some channels allow only low power transmissions. Error beeps will
sound if attempting to change the transmission power while on one
of these channels.
Some channels allow only low power transmissions initially, but can
be overridden to high power by pressing (and holding) H/L after
depressing PTT. Keep the H/L button pressed down after releasing
the PTT button, if wanting to transmit again on high power.
15. Channel change (Handset mic and wireless handset)
Short press () goes up one channel, or () goes down one
General Information | RS40/RS40-B User Guide
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