![background image](http://html1.mh-extra.com/html/icom/im304/im304_instruction-manual_4299624015.webp)
9
3
BASIC OPERATION
3
■
Microphone lock function
The microphone lock function electrically locks
[
Y
]
and
[
Z
]
keys on the supplied microphone. This prevents accidental
channel changes and function access.
➥
While pushing and holding
[HI/LO]
on the microphone,
turn power ON to toggle the Microphone lock function ON
and OFF.
■
Display backlighting
The function display and keys can be backlit for better visibil-
ity under low light conditions.
➥
While pushing and holding
[SCAN]
, push
[
Y
Y
]
or
[
Z
Z
]
to ad-
just the brightness of the LCD and key backlight.
• The backlight is selectable in 3 levels and OFF.
■
AquaQuake water draining
function
The IC-M304 uses a new technology to clear water away
from the speaker grill: AquaQuake. AquaQuake helps drain
water away from the speaker housing (water that might oth-
erwise muffle the sound coming from the speaker). The IC-
M304 emits a vibrating noise when this function is being
used.
➥
While pushing and holding
[
Y
]
and
[
Z
]
, turn power ON.
• A low beep tone sounds while
[
Y
]
or
[
Z
]
keys are held to drain
water, regardless of
[VOL]
control setting.
• The transceiver never accepts a key operation while the
AquaQuake function is activated.
• “
” scrolls at the channel comment indicator.
Scrolls
[
Y
]/[
Z
]
[HI/LO]