GME GX400B - Manual (Page 6)

6 I N S T R U C T I O N M A N UA L G X 4 0 0
GENERAL OPERATION
VOLUME ON/OFF
To turn the GX400 on, briefly press the key.
To adjust the volume, rotate the volume control. Rotate the volume control clockwise to increase
the volume or counter-clockwise to reduce the volume.
NOTE: At minimum volume setting there is still sufficient volume to be heard in a quiet cabin
environment.
To turn the GX400 off, press and hold the key again.
SQUELCH CONTROL
The squelch control is used to eliminate the background noise when there are no signals
present. To adjust the squelch, first rotate it fully counter-clockwise until the background noise
is heard, then slowly rotate it clockwise until the noise disappears. If there are signals on the
channel, you should wait until the channel is clear (or select a quiet channel) before adjusting
the squelch.
Once adjusted, the receiver will remain quiet as long as there are no signals present, but
an incoming signal will override the squelch and be heard in the speaker. As the control is
advanced further clockwise the squelch action is progressively increased and stronger incoming
signals are needed to override it. To receive very weak signals or to disable the squelch, simply
turn the control fully counter-clockwise.
CHANNEL SELECTION
Select the required channel by briefly pressing the or keys. The selected channel is
displayed on the LCD. Press and hold either key to quickly advance upwards or downwards
through the channels. Release the key when the required channel is displayed.
DISPLAY BRIGHTNESS
The LCD has three brightness levels to provide suitable lighting for day or night use.
To adjust the brightness
Briefly press the key to cycle through the display brightness settings. The display brightness
will cycle through Off, Dim and Bright. If the radio is switched off the selected brightness level
will be retained in memory and will be restored when the radio is switched on again.
TRANSMITTING
To transmit, press the PTT on the microphone. Hold the microphone 2 – 6 cm from your mouth
and slightly to one side so your voice does not project directly into the microphone. Speak at a
normal voice level. Your GX400 has a build-in speech processor which automatically controls
the level of your transmitted voice. It is not necessary to raise your voice or shout into the
microphone. Release the PTT to receive.
NOISE LIMITER
The NL key activates an extremely effective noise limiter circuit which helps to eliminate
most electrical impulse interference caused by engine ignition systems etc. This allows clearer
reception of weak signals even under noisy electrical conditions. When the noise limiter is
selected, ‘NL’ is displayed on the LCD.