Standard Horizon HX300 Owner's Manual page 19

Keypad
Key
Pressing this key immediately recalls channel 16 from any channel loca-
tion. Holding down this key recalls channel 9. Pressing this key again
reverts to the previous selected working channel.
Key
Press to stop the Scan, Priority Scan, Dual or Tri-Watch feature.
Secondary use:
Press and hold this key to immediately recall the last-used NOAA (National
Oceanic and Atmospheric Administration) Weather Channel from any
channel location. Recalls the previously- selected working channel when
the key is pressed again.
Advanced use:
When the key is held and the key is pressed, the radio will
change the marine band between the USA, International, and Canadian
channels.
Key
Press this key to toggle the transmitter output power between "High"
(5 Watts) and "Low" (1 Watt) power. This key does not function on the
"Transmission Inhibited" and "Low power only" channels.
Secondary use:
Hold down this key to lock the keypad (except the , and PTT
keys) so that they are not accidentally changed. The " " Keylock icon
will appear at the top left on the display, to indicate that the functions are
locked. Hold down this key until the " " Keylock icon disappears to un-
lock the radio.
Key
Press this key to change the operating channel, receiver volume level,
and squelch threshold level.
Press the key momentarily, the channel (or level) will increase one step.
Holding the key, the channel (or level) will increase continuously.
Key
Press this key to change the operating channel, receiver volume level,
and squelch threshold level.
Press the key momentarily, the channel (or level) will decrease one step.
Holding the key, the channel (or level) will decrease continuously.
Key
Press and hold this key for two seconds to turn the radio "on" or "off".
HX300 Page 19