Nexus NX2500 User manual

Installation and Operation Manual
English
Marine VHF Radio
with Navtex and GPS repeater
Installation and Operation Manual
English
NX2500

VHF NX2500 English
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English VHF NX2500
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Contents
1OPERATION RULES .................................................................. 4
1.1 Priorities .........................................................................................................4
1.2 Privacy ...........................................................................................................4
1.3 Radio licenses................................................................................................4
1.3.1 Ship station license ....................................................................................4
1.3.2 Operator’s license ......................................................................................4
2INTRODUCTION ......................................................................... 5
3PANEL DESCRIPTION ............................................................... 6
3.1 Front panel .....................................................................................................6
3.2 Back panel .....................................................................................................7
3.3 LCD Display ...................................................................................................8
4FIST MICROPHONE/CONTROLLER ......................................... 9
4.1 Soft Keypad (0 - 9) .........................................................................................9
5GENERAL OPERATION ........................................................... 11
5.1 DUAL WATCH (DW) ....................................................................................12
5.2 Full Scan (FS) ..............................................................................................12
5.3 Memory Scan (MS) ......................................................................................12
5.4 Tag Channel.................................................................................................12
5.5 Squelch Control............................................................................................13
5.6 Volume Control (VOL)..................................................................................13
5.7 Channel 16 (16) ...........................................................................................13
5.8 Channel Selection (▲/▼).............................................................................14
5.9 HIGH / LOW Power Selection (H/L) .............................................................14
5.10 Time Out Timer ............................................................................................14
6RECEIVING A DSC CALL ........................................................ 15
6.1 DISTRESS ALERT.......................................................................................15
6.2 ROUTINE CALL ...........................................................................................15
6.3 SAFETY / URGENCY CALL ........................................................................15
6.4 GROUP CALL ..............................................................................................16
6.5 DISTRESS RELAY ......................................................................................17
6.6 SEA CALL....................................................................................................17
7SENDING A DSC CALL............................................................ 18
7.1 DISTRESS CALL .........................................................................................18
7.2 ROUTINE CALL ...........................................................................................18
7.3 SAFETY CALL .............................................................................................19
7.4 URGENCY CALL .........................................................................................20
7.5 GROUP CALL ..............................................................................................20
7.6 DISTRESS RELAY ......................................................................................21
8LOG REVIEW............................................................................ 22
8.1 Review Routine Log .....................................................................................22
8.2 Review distress logs.....................................................................................23
9DSC Setting .............................................................................. 24
9.1 Enter and view MMSI ...................................................................................24
9.2 Set Group Id.................................................................................................25
9.3 Set Manual Position/UTC.............................................................................26

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9.4 Set the Directory .......................................................................................... 26
10 RADIO SETTINGS .....................................................................29
10.1 Backlight adjustment.................................................................................... 29
10.2 Contrast adjustment..................................................................................... 29
10.3 Speaker selecting ........................................................................................ 29
10.4 Beep sound selecting................................................................................... 30
10.5 Navtex Only-Mode ....................................................................................... 30
10.6 Set Date And TimE ...................................................................................... 31
11 NAVTEX Messages Settings....................................................32
11.1 Navtex messages ........................................................................................ 32
11.2 Station Select............................................................................................... 33
11.3 Message Select ........................................................................................... 35
11.4 Clear all Messages ...................................................................................... 35
11.5 Clear Selected Messages ............................................................................ 36
11.6 Clear Selected Messages ............................................................................ 36
12 EXPANSION CHANNELS .........................................................37
13 ATIS FUNCTION........................................................................37
14 Technical Specifications .........................................................38
14.1 RECEIVER .................................................................................................. 38
14.2 CHANNEL 70 MONITOR GENERAL SPECIFICATION .............................. 39
14.3 TRANSMITTER ........................................................................................... 39
14.4 NAVTEX ...................................................................................................... 39
14.5 GPS ............................................................................................................. 39
15 International VHF Marine Channel Chart................................40
16 Installation ................................................................................41
16.1 Unit Installation ............................................................................................ 41
16.2 Antenna Installation Recommendations....................................................... 42
17 Supplied Parts ..........................................................................44
18 WARRANTY...............................................................................45
19 DECLARATION OF CONFORMITY ..........................................48

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1 OPERATION RULES
1.1 Priorities
• Read all rules and regulations pertaining to priorities and keep an up-to-date copy
handy. Safety and distress calls take priority over all others.
• You must monitor Channel 16 when you are not operating on another channel.
• False or fraudulent distress calls are prohibited under law.
1.2 Privacy
• Information overheard but not intended for you cannot lawfully
Be used in any way.
• Indecent or profane language is prohibited.
1.3 Radio licenses
1.3.1 Ship station license
When your craft is equipped with a VHF FM transceiver, you must have a current radio
station license before using the transceiver. It is unlawful to operate a ship station which
is not licensed. Inquire through your dealer or the appropriate government agency for a
Ship-Radiotelephone license. This license includes the call sign which is your craft’s
identification for radio purposes.
1.3.2 Operator’s license
A restricted Radiotelephone Operator Permit is the license most often held by small
vessel radio operators when a radio is not required for safety purposes. The Restricted
Radiotelephone Operator Permit must be posted near the transceiver or be kept with
the operator. Only a licensed radio operator may operate a transceiver. However, non-
licensed individuals may talk over a transceiver if a licensed operator starts, supervises,
ends the call and makes the necessary log entries. A current copy of the applicable
government rules and regulations is only required to be on hand for vessels in which a
radio telephone is compulsory. However, even if you are not required to have these on
hand it is your responsibility to be thoroughly acquainted with all pertinent rules and
regulations.

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2 INTRODUCTION
The NX2500 is a Class-D Digital Selective Calling (DSC) VHF marine
transceiver. The NX2500 can also display Navtex information if the
Navtex antenna NX2600 is connected. The NX2500 has also the
capability to repeat the most important navigational information if it is
connected to a GPS navigator / Plotter. Comprised of a VHF marine
Radio and a DSC controller, it is very convenient and easy to use. The
transceiver is a 1/25-watt, frequency modulated waterproof
transmitter/receiver for operations on all currently allocated marine
channels as well as 10 expansion channels.
The NX2500 supports the latest GMDSS requirement for non-SOLAS vessels from the
International Maritime Organization (IMO). When connected with a GPS, it will display
the position and Universal Time Coordinate (UTC) of your vessel.
The NX2500 lets you make digitally selected calls, which are quicker and simpler to
make compared with conventional voice calls using channel 16. Should a distress,
urgency or safety situation occur, you can depend on the NX2500 to raise an alert
quickly, thereby indicating your identity and position automatically through a distress
communication on the emergency voice channel.
NEXUS MARINE AB operates a policy of continual development and reserves the right
to alter and improve the features/specification of their products without prior notice.

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3 PANEL DESCRIPTION
3.1 Front panel
1. POWER SWITCH (ON)
Press the (ON) button once to switch on the NX2500.
To switch off, press the (ON) button again.
2. HIGH/LOW POWER KEY (H/L)
Select an output power of RF.
3. CLEAR KEY (CLR)
Stops current task and returns to the main screen.
4. SQUELCH MODE SELECTION KEY (SQ)
5. VOLUME CONTIOL MODE SELECTION KEY (VOL)
6. FUNCTION SELECT KEY (F)
This key is an aggregation of DUAL WATCH, FULL SCAN, MEMORY SCAN and
TAG CHANNEL function. To access these function by press F key and press again
to confirm.
7. DOWN KEY (▼)
Selects the desired channel, squelch control level or volume control level. Each
press selects the next lower channel number or level. Hold down this key to scroll
downwards through all selectable channels.
8. CHANNEL 16 KEY (16)
Press this key and return to channel 16 immediately from any channel or function.

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9. UP KEY (▲)
Selects the desired channel, squelch control level or volume control level. Each
press selects the next higher channel, number or level. Hold down this key to
scroll upward through all selectable channels.
10. LIQUID CRYSTAL DISPLAY (LCD)
Dot Matrix display, giving up to 8 lines of information.
11. SPEAKER
12. DISTRESS CALL BUTTON
The distress button is located under a spring-loaded cover that must be lifted
before the button can be pressed.
13. FIST MICROPHONE/CONTROLLER CORD
3.2 Back panel
1. POWER CORD
2. GPS, Navtex and EXT.SP socket.
3. ANTENNA
4. Ventilation Hole
Should the display show signs of misting up, remove this screw and
ventilate the unit until the mist is cleared. Upon completion, insert the screw
and tighten once again.
Note : To ensure your NX2500 maintains its water-proof integrity, please
make sure the water-proof plastic washer is properly inserted before the
screw; the screw should be fully tightened to prevent water ingress.

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3.3 LCD Display
GROUP 1
VL Volume control activated, the Bar indicates the volume level.
Sq Squelch control activated, the Bar indicates the squelch level.
Mu Appears when the squelch opens.
RX The Radio is in receptive state (RX) and when receiving a signal.
TX The Radio is transmitting (TX).
GROUP 2
Hi Indicates Transmitter maximum output power is 25W.
Lo Indicates Transmitter maximum output power is 1W.
GROUP 3
S Indicates the displayed channel is a simplex channel.
D Indicates the displayed channel is a duplex channel.
GROUP 4
I Indicates the international channels are selected.
K Indicates the international channels + UK M1 and M2 channels are
selected.
U Indicates the USA channels are selected.
C Indicates the Canada channels are selected.
A Indicates the ATIS channels are selected.
S Indicates the ATIS SEA channels are selected.
GROUP 5
DW Indicates dual watch is in operation.
FS Indicates full scanning of every channel in current channel list is in operation.
MS Indicates scanning of the selected memory channels is in operation.
GROUP 6
M Indicates the displayed channel is a tagged channel for memory scan.
GROUP 7
Date/hours: minutes

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4 FIST MICROPHONE/CONTROLLER
The fist microphone/controller has the microphone, Push to Talk (PTT) switch and soft
keypad as illustrated below:
4.1 Soft Keypad (0 - 9)
The telephone style keypad ITU 0 – 9 / A - Z is used for entering numeric data. When
required, the keys will automatically switch to character mode allowing letters, numbers
and punctuation marks to be entered. Repeatedly pressing a key will cycle through the
characters available on that key.
Number 1 2 3 4 5 6 7 8 9 0
1 press — A D G J M P T W
2 press , B E H K N Q U X 
3 press  C F I L O R V Y 
4 press /    ” ’ S & Z %
5 press 1 2 3 4 5 6 7 8 9 0

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ENTER KEY (ENT)
Confirms the action.
CLEAR KEY (CLR)
Stop tasks and returns to main screen or returns to the last screen.
◄/ ►Key
Used to select stored numbers and names as marked by the cursor, or to select
through the call log.
▲/ ▼KEY
Use to select working channel (Up or Down). Can also be used to select stored working
channels. Allows viewing of next or previous message and selection next or previous
item.
PTT BUTTON
Keys the transmitter allowing you to transmit a message.
(CALL) KEY.
Activates “CALL” menu.
(MENU) KEY
To activate a menu that consists of RADIO SETTING, DSC SETTING and LOG
REVIEW function.

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5 GENERAL OPERATION
The NX2500 is switched on by pressing the (ON) key once. If a GPS receiver has been
connected to the NX2500, the MAIN screen will be as below:
Press the (F) key on the front panel once to enter the Function Selection mode. The
FUNCTION SELECTION screen will be displayed as below:
Press the ▲or ▼key to move the cursor to the required function (DUAL WATCH,
FULL SCAN, MEMORY SCAN, TAG CHANNEL), then press (F) key to confirm. The
relevant screen will be displayed. Press (F) key again or press (16) key to restore
normal operation, and press (CLR) key to change to the main screen.

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5.1 DUAL WATCH (DW)
Dual Watch enables the Radio to scan between the selected channel and priority
channel (normally CH16). In Dual Watch mode, the DW indicator will appear on the
bottom line of the LCD.
Note that the Radio will not transmit, nor will alternative channels be able to be selected
while in Dual Watch mode. To restore normal operation press (F) key again or press
channel (16) key.
5.2 Full Scan (FS)
This function scans through each channel sequentially until a signal is detected above
the squelch level set. Once the signal ends or drops below the squelch level, the Radio
will continue scanning. Alternatively, you can instruct the NX2500 to continue scanning
even if a signal has been detected on any particular channel by pressing the ▲key
once. When in Full Scan mode, FS will appear on the bottom line of LCD.
Note that the Radio will not transmit, nor will alternative channels be able to be selected
while in Full Scan mode. To restore normal operation press (F) key or press channel
(16) key.
5.3 Memory Scan (MS)
The Memory Scan operates in the same way as the Full Scan, except that it will only
scan channels that have been entered into the Scan Memory. If no channels have been
entered into the memory then this function will not be available.
When in Memory Scan mode, “MS” will appear on the bottom line of the LCD.
5.4 Tag Channel
This function is to tag or cancel tag on a channel, which means select or unselect a
channel for Memory Scan. If a channel is tagged then the “M” indicator will appear on
the bottom of LCD.
To tag a channel, enter the desired channel number on the Microphone controller and
press “F” on the front panel. Select TAG CHANNEL and press “F” again. To delete the
tag for a channel, repeat the procedure above.

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5.5 Squelch Control
When the (SQ) key on the front panel is pressed, the squelch level bar and “Sq” symbol
will appear at the right side of the screen as below:
Then use ▲and ▼key on the front panel to adjust the receiver muting threshold
(squelch) level.
To cut out weaker signals, press ▲key to increase the squelch until the background
interference noise disappears. To receive weaker signals press ▼key to decrease the
squelch.
5.6 Volume Control (VOL)
Press the (VOL) key on the front panel, the volume control screen will be displayed.
The level bar and character “VL” will appear on the right side of the screen as below:
Press ▲key to increase the volume. Press ▼key to reduce the volume.
5.7 Channel 16 (16)
Pressing the (16) key will automatically select channel 16 on high power. Any active
function (DUAL WATCH, DSC SETTING, LOG VIEW etc) will be cancelled.

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5.8 Channel Selection (▲/▼)
Press ▲key to go up through the channels. Press ▼key to go down through the
channels.
Channel Selection Shortcut:
Select the desired channel directly from the main screen by pressing the channel
number on the fist microphone/controller, and then press “ENT” to confirm.
5.9 HIGH / LOW Power Selection (H/L)
Press (H/L) key to select high or low output power of RF. A “Hi” or “Lo” indicator will
appear on bottom of LCD.
5.10 Time Out Timer
A time out timer is provided to prevent continuous transmissions for periods greater
than 5 minutes. In the event that the radio will be needed to transmit for periods longer
than 5 minutes, it will be necessary to release the PTT briefly before the 5 minute timer
expires.
WARNING
1) Users can press the PTT once again after 5 minutes to continue the transmission.
But the radio should be placed somewhere which nobody can touch it to avoid
scalding injury.
2) The life of the radio set will be shortened by long time continuous transmission.

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6 RECEIVING A DSC CALL
6.1 DISTRESS ALERT
When receiving the DISTRESS ALERT, the radio will give off the alarm and display as
follows, then jump to the 16 channel automatically, press the ENT key to confirm the
alarm and monitor the communication at the same time, press the CLR to cancel the
displaying text
6.2 ROUTINE CALL
When receiving the ROUTINE CALL, the radio will give off the B-B sound and display
as follow, press the ENT key to transmit the response call, the radio will jump to the
working channel, waiting for the call. Press the CLR key to cancel the B-B sound, and
then return to the main interface.
6.3 SAFETY / URGENCY CALL
When receiving the SAFETY/URGENCY CALL, the radio will give off the B-B sound
and display as follows. If the format of the SAFETY /URGENCY CALL is ALL SHIP, the
radio will display ALL SHIP, if the format of the SAFETY/URGENCY CALL is
INDIVIDUAL it will display INDIVIDUAL, press the ENT key to transmit the response
call, the radio will jump to the working channel, waiting for the call. Press the CLR key
to cancel the alarm, then return to the main interface.

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6.4 GROUP CALL
When receiving the GROUP CALL, the receiver will give off the B-B sound and display
as follows. The radio will jump to the working channel, waiting for the call, press the
ENT key to cancel the B-B sound.

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6.5 DISTRESS RELAY
When receiving the DISTRESS RELAY CALL, the radio will give off the alarm and
display as follows (transmit the ID of calling ship, the ID of the ship in danger, the
danger categories of the ship in dangerous, orientation and time), press the CLR key to
cancel the alarm, then return to the main interface.
6.6 SEA CALL
When receiving the SEA CALL, the radio will give off the B-B sound, the display will
show as follows (display the receiver’s MMSI code and the area coordinate). Press the
ENT key to cancel the B-B sound, then jump to the working channel.

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7 SENDING A DSC CALL
7.1 DISTRESS CALL
Press and hold the DIST button on the front for 5seconds and the distress call will be
send. If you have more time, you may press a short press on the DIST button and
then select the nature of distress with ◄or ►. Then press and hold DIST for 5 sec.
7.2 ROUTINE CALL
Press the CALL key on the hand controller, choose the ROUTINE CALL. Input the
receiver’s MMSI code, then press the▲or ▼to move the cursor to the NO line, input
the working channel number, then press the ENT to transmit the ROUTINE CALL. The
radio is waiting for response.

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7.3 SAFETY CALL
Press the CALL key on the hand controller, choose the SAFETY CALL, then press the
◄or ►key to choose ALL SHIP/INDIVIDUAL. If you choose the INDIVIDUAL, you
need to input the receiver’s MMSI code, then press the▲or ▼to move the cursor “_”
to the NO line, input the working channel number, then press the ENT key. then press
the ENT key again to confirm the transmitting, after receiving the receiver’s response,
the radio will jump to the working channel automatically. Press the CLR to cancel the
transmitting.