GME GX750 User manual

GX750 INSTRUCTION MANUAL 1
GX750 VHF marine radio
with remote full function LCD controller microphone
INSTRUCTION MANUAL

2 INSTRUCTION MANUAL GX750
CONTENTS
WARNING/SAFETY INFORMATION............................................................................................3
OPERATOR QUALIFICATIONS....................................................................................................3
INTRODUCTION .......................................................................................................................3
FEATURES................................................................................................................................3
SUPPLIED WITH........................................................................................................................4
RANGE ....................................................................................................................................4
CONTROLS...............................................................................................................................4
OPERATION .............................................................................................................................5
On/Off..............................................................................................................................5
Volume.............................................................................................................................5
Adjusting the squelch.......................................................................................................6
Channel selection.............................................................................................................6
Keypad lock......................................................................................................................7
Transmitting.....................................................................................................................7
Channel 16.......................................................................................................................7
Display backlighting .........................................................................................................8
High/Low power selection................................................................................................8
Working channel memories ..............................................................................................8
Dual Watch key (DW) .......................................................................................................8
Dual Watch features.........................................................................................................9
Triple Watch key (TW) ......................................................................................................9
Triple Watch features......................................................................................................10
Scanning ........................................................................................................................11
Scanning features........................................................................................................... 11
INSTALLATION .......................................................................................................................12
Selecting a location........................................................................................................13
Installing the main unit...................................................................................................13
Antenna installation.......................................................................................................15
SPECIFICATIONS ....................................................................................................................16
Electrical ........................................................................................................................16
Mechanical.....................................................................................................................17
Environmental................................................................................................................17
INTERNATIONAL VHF MARINE CHANNELS..............................................................................18
STANDARD COMMUNICATIONS WARRANTY AGAINST DEFECTS.............................................19

GX750 INSTRUCTION MANUAL 3
WARNING/SAFETY INFORMATION
•The GX750 is a radio transmitting device.
•When transmitting, keep any part of your head or body more than 20 cm from
the antenna.
•Do not transmit near electrical blasting equipment or in explosive atmospheres.
•Do not allow children to operate a radio transmitter unsupervised.
OPERATOR QUALIFICATIONS
Any person in Australia operating a VHF marine radio should possess at least a Short Range
Radio Operators Certificate of Proficiency (SROCP). Alternatively, operators may obtain a Long
Range Radio Operators Certificate of Proficiency (LROCP), which covers the operation of both
VHF and MF/HF equipment.
Many TAFEs and marine organisations offer courses leading to examination for the SROCP and
LROCP although such courses are not compulsory. Persons wishing to obtain the SROCP or
LROCP should first purchase a copy of the Maritime Radio Operator Handbook which is essential
reading for every boat owner in Australia.
The Australian Maritime College (AMC) provides the marine examination and certificate service
on behalf of the Australian Communications and Media Authority (ACMA). The AMC can
provide the details of organisations and individuals offering courses and or conducting exams.
For further information visit: www.amc.edu.au
INTRODUCTION
Congratulations. You have just purchased one of the most technically advanced VHF marine
radios in the world.
The GME GX750 is a VHF radio designed to operate in the 156–163 MHz marine band.
The GX750 has a number of enhanced features including full function LCD controller
microphone, user programmable Channel Scanning, Dual Watch and Triple Watch functions
and two programmable ‘Instant’ channel memories.
With its compact size and IPX7 design it can easily be installed into almost any mounting
location in your flybridge or cabin.
The GX750 is designed in Australia at our Sydney facility.
FEATURES
•Full Function LCD Controller Microphone
•Compact Modular IPX7 Design
•Selectable International, USA, and Canadian Channel Sets
•Selectable USA and Canadian Weather Channels
•Dual Watch and Triple Watch with Programmable Priority Channel
•Programmable Channel Scanning
•Selectable Power 25/1 watt
•Two Working Channel Memories
•Adjustable Digital Squelch

4 INSTRUCTION MANUAL GX750
SUPPLIED WITH
GX750 main unit
GX750 LCD controller microphone
(MC750B/W)
Mounting hardware
Microphone bracket (MB210B/W)
Microphone clip (MB209B/W)
S0239 to FME adaptor (AD513)
8 pin panel socket (MK013B/W)
DC power lead (LE029)
500 mm interconnecting lead (LE106)
Instruction manual
Cable Tie
RANGE
The range of VHF transmissions depend on antenna height, transmitter power and the terrain
over which the signals pass. Ship to ship communications should be possible over at least 8
nautical miles and up to about 27 nautical miles. Ship to shore ranges will often be greater due
to the increased height of the shore antenna and communications of 25 to 50 nautical miles are
possible.
CONTROLS
Rear Panel Controller Microphone Socket
DC Cable Extension Speaker Socket
Antenna Socket
LCD Display
Dual Watch Triple Watch Scan Keypad Lock
AB
Safety Channel
Selected
Scan Memory
Channel Suffix
Priority Channel 1
Priority Channel 2
Weather
Channel Set
Channel Prefix
Channel Number
Busy Low Power Transmit

GX750 INSTRUCTION MANUAL 5
AB
OPERATION
ON/OFF
To turn the GX750 ON, press and hold the key.
To turn the GX750 OFF, press and hold the key.
VOLUME
Press the or keys to adjust the volume. Press the key to increase the volume or the
key to decrease the volume. The volume level is shown on the display as 01 (minimum) to 19
(maximum).
NOTE: When adjusting the volume, the left digit is deliberately displayed smaller to minimise
confusion with the channel number.
Minimum Volume (01) Maximum Volume (19)
NOTE: At minimum volume setting there is still sufficient volume to be heard in a quiet
cabin environment.
Push-To-Talk
Channel
Volume Up
Volume Down
Priority 1
Priority 2
Lamp/Weather
Channels
Channel 16
LCD
Scan
Squelch
Microphone
Dual Watch
Triple Watch
Low Power/
Keypad Lock
Speaker
LCD CONTROLLER
MICROPHONE
Power

6 INSTRUCTION MANUAL GX750
ADJUSTING THE SQUELCH
To open the squelch, briefly press the SQL key. A low beep will be heard and the squelch will
open. Briefly press the SQL key again to close the squelch. A high beep will be heard and the
squelch will be restored to its preset level.
Setting the squelch preset level
The preset squelch level can be adjusted to suit local conditions. If you are in an electrically noisy
location or unwanted weak signals keep opening the squelch, you can adjust the squelch setting
so that the GX750 remains quiet. Note that increasing the preset squelch level will mean that
stronger signals will be required to overcome the squelch and may result in missed calls from
weaker signals. The best setting is the minimum one required to keep the receiver quiet.
To alter the preset squelch setting, press and hold the SQL key until a high beep is heard.
The present squelch setting will be displayed in digits from -0 (minimum) to -9 (maximum)
squelch. While in this mode, briefly rotate the channel control left or right to increase or
decrease the squelch level respectively as required. Press the SQL key again to exit the squelch
setting mode (or wait 5 seconds and it will time out automatically). A low beep will be heard.
Minimum Squelch (-0) Maximum Squelch (-9)
CHANNEL SELECTION
Standard Marine Channels
Select the required channel by rotating the channel control left or right. The selected channel
number is displayed.
Channel sets
The GX750 is programmed with three channel sets – International, USA and Canada. These
channel sets support various channel and frequency allocations for other parts of the world.
When operating in Australia or New Zealand, the International channel set should be selected.
Once you have selected the required channel set for your location, you should not need to
change it again unless you have moved to another country.
To select the required channel set
Switch the GX750 OFF
•Press and hold the 16 key while switching the GX750 ON again.
•Channel 16 will be selected and the presently selected channel set will flash on the display
as INTL, USA or CAN.
•Briefly press the 16 key to cycle through the channel set selections in the following order:
International Canada USA
The selected channel set becomes active immediately.

GX750 INSTRUCTION MANUAL 7
•Once the required channel set is selected, hold the 16 key to return to normal operation.
NOTE: The radio will automatically return to normal operation after 20 seconds.
NOTE: Weather channels are also available when the USA and Canada channel sets
are selected.
Weather Channels
Weather channels are available only when the USA or Canadian channel sets have been
selected. There are no allocated weather channels in the International channel set.
To access the weather channels while in the USA or Canada channel set, press and hold WX.
The ‘WX’ icon is displayed. Now rotate the channel control to select from the available weather
channels. To return to normal channels press and hold WX again. The ‘WX’ icon will disappear.
KEYPAD LOCK
The keypad lock prevents accidental key presses from altering the operation of the radio
unexpectedly.
To lock the keypad, press and hold the key. The symbol will be displayed and all keys
are disabled except for the , 16, Volume, PTT, and keys.
To unlock the keypad press and hold the LOCK key again. The symbol will disappear and
the keypad will be enabled.
TRANSMITTING
To transmit, press the PTT (Push to Talk) on the microphone. Hold the microphone about 3 – 5
cm from your mouth and speak at a normal voice level. The microphone is quite sensitive so it is
not necessary to raise your voice or shout. Release the PTT when you have finished talking.
Time-Out-Timer
Transmission time is controlled by a time-out timer. If the PTT is held for more than 5 minutes,
a low beep will be heard and the transmitter will be temporarily disabled to prevent accidental
jamming of the channel frequency. To reset the timer simply release the PTT.
NOTE: The transmitter is permanently disabled on CH 70. If the PTT is pressed on CH 70, a low
beep will be heard and the PTT will be ignored.
CHANNEL 16
Briefly press the 16 key to switch straight to channel 16. The ‘SAFETY’ icon will be displayed, all
previous control settings (such as scanning or low transmitter power) will be cancelled and the
radio will be restored to normal operation with high transmitter power selected. Press the 16
key again to return to the selected channel.

8 INSTRUCTION MANUAL GX750
DISPLAY BACKLIGHTING
The LCD display and keys are backlit for easy viewing at night.
Brightness Adjustment
To set the brightness of the LCD backlighting, briefly press the key. Each press will cycle
through the following brightness settings.
Off Dim Bright
Colour Selection
To change the backlight colour, press and hold the channel control. Each press will toggle the
backlighting between white and red.
NOTE: When the red backlight is selected, the 16 key remains backlit in white
HIGH/LOW POWER SELECTION
To switch between High and Low transmit power, briefly press the LO key. A high beep
indicates that High power is selected (25 watts) while a low beep indicates Low power is
selected (1 watt). When low power is selected ‘LO’ is displayed.
NOTE: Selecting channel 16 automatically resets the transmitter to high power.
WORKING CHANNEL MEMORIES
The GX750 has two dedicated priority channel memories that allow you to store and recall two
often-used channels. These memories are accessed using keys labelled PR1 and PR2. PR1 is
also used as the priority channel for the Triple Watch function (see feature description later in
this manual).
Storing Priority Memories (PR1/PR2)
To store a channel in the PR1 or PR2 memory, select the required channel using the channel
control, then press and hold the PR1 or PR2 key. The channel number will flash then a high
beep will be heard as the channel is stored.
Recalling Priority Memories (PR1/PR2)
Briefly press the PR1 or PR2 key. The radio will switch immediately to the channel stored in that
memory and ‘PR1’ or ‘PR2’ is displayed. If the radio was scanning the scan will be cancelled.
DUAL WATCH KEY (DW)
The Dual Watch function is a two-channel scan feature where the GX750 switches between
channel 16 and any other selected channel. This feature allows you to monitor a working or club
channel while still being able to receive important broadcasts on channel 16.
Example of the Dual Watch sequence
(S = selected channel)
To use the Dual Watch function, select your preferred operating channel – either by rotating the
channel control or by selecting one of the stored PR1 or PR2 memories – then press the DW
16 S

GX750 INSTRUCTION MANUAL 9
key. A high beep will be heard and the ‘DW’ icon will appear on the display. The GX750 will
now monitor both the selected channel AND channel 16 by alternating equally between them.
To cancel the Dual Watch
Briefly press the DW key to return to normal operation. A low beep will be heard.
DUAL WATCH FEATURES
If a signal appears on the selected channel
Scanning will pause on the selected channel but channel 16 will continue to be monitored every
2 seconds resulting in short breaks in the reception of the selected channel. During this time the
PTT may be pressed for normal transmissions on the selected channel (monitoring of channel
16 pauses while transmitting). Once the selected channel has become inactive for 5 seconds the
Dual Watch function will resume.
If a signal appears on channel 16
The radio will switch immediately to channel 16 and the selected channel will no longer be
monitored because channel 16 has priority. During this time the PTT may be pressed for normal
transmissions on channel 16. Once channel 16 has become inactive for 5 seconds the Dual
Watch function will resume.
To transmit on the selected channel while Dual Watching
Simply press the PTT. The Dual Watch function will pause and the radio will transmit on the
selected channel. Dual Watch will then resume 5 seconds after all activity has ceased on the
channel.
To transmit on channel 16 while Dual Watching
Press the 16 key to switch to channel 16. Dual Watch will be cancelled and the radio will
switch straight to channel 16 and the ‘SAFETY’ icon will be displayed. Now press the PTT and
transmit in the usual way. When your conversation has ended, press the DW key to resume Dual
Watching.
To change the working channel while Dual Watching
While Dual Watching, simply rotate the channel control to select another working channel.
Alternatively you can select one of the stored PR1 or PR2 memories. Dual Watching
automatically continues using the newly selected channel.
TRIPLE WATCH KEY (TW)
Triple Watch is an extension of the Dual Watch feature. It allows the GX750 to monitor channel
16, a selected working channel AND the PR1 channel memory. Each channel is scanned equally
for signals with priority given first to channel 16, then the PR1 channel and lastly the selected
channel.
Example of the Triple Watch sequence
(S = selected channel)
When Triple Watch is selected, the ‘TW’ icon is displayed.
16 S
Pr1

10 INSTRUCTION MANUAL GX750
To use the Triple Watch mode, first program your priority channel into the PR1 memory, then
select your preferred working channel by rotating the channel control. Now press the TW key.
A high beep will be heard and the ‘TW’ icon will be displayed. The GX750 will now monitor
channel 16, the PR1 channel and the selected channel by alternating equally between them.
To cancel Triple Watch
Press the TW key to return to normal operation. A low beep will be heard.
TRIPLE WATCH FEATURES
If a signal appears on channel 16
The radio will switch immediately to channel 16 and ‘16’ will be displayed. At this point the
selected channel and the priority channel are no longer being monitored because channel 16
has highest priority. During this time the PTT may be pressed for normal transmissions on
channel 16. Once channel 16 has become inactive for 5 seconds the Triple Watch function will
resume.
If a signal appears on the Priority channel
Scanning will pause on the priority channel BUT channel 16 will continue to be monitored every
2 seconds (the selected channel is not monitored). During this time the PTT may be pressed
for normal transmissions on the priority channel (monitoring of channel 16 pauses while
transmitting). Once the priority channel has become inactive for 5 seconds Triple Watch will
resume.
If a signal appears on the selected channel
Scanning will pause on the selected channel BUT channel 16 and the priority channel will
continue to be monitored every 2 seconds. During this time the PTT may be pressed for normal
transmissions on the selected channel (monitoring of channel 16 and the priority channel pauses
while transmitting). Once the selected channel has become inactive for 5 seconds the Triple
Watch will resume.
To transmit on the selected channel while Triple Watching
Simply press the PTT. The Triple Watch function will pause during the transmission and remain
paused until 5 seconds after all activity has ceased on the selected channel. Triple Watch will
then resume.
To transmit on the Priority channel while Triple Watching
Briefly press the PR1 key. Triple Watch will be cancelled and the priority channel will be
selected. Now press the PTT and transmit in the usual way. When your conversation has ended,
press the TW key to return to the Triple Watch function.
To transmit on channel 16 while Triple Watching
Press the 16 key. Triple watch will be cancelled and the radio will switch straight to channel 16.
Now press the PTT and transmit in the usual way. When your conversation has ended, press the
TW key to return to the Triple Watch function.