JPS NXU-2A User manual
NXU-2A Operations Manual
ii Interoperability Now!
FEDERAL COMMUNICATIONS COMMISSION
(FCC) COMPLIANCE NOTICE:
RADIO FREQUENCY INTERFERENCE NOTICE
This equipment has been tested and found to comply with the limits for a Class
A digital device, pursuant to Part 15 of the FCC Rules. These limits are
designed to provide reasonable protection against harmful interference when
the equipment is operated in a commercial environment. This equipment
generates, uses, and can radiate radio frequency energy and, if not installed and
used in accordance with the instruction manual, may cause harmful
interference to radio communications. Operation of this equipment in a
residential area is likely to cause harmful interference in which case users will
be required to correct the interference at their own expense.
CAUTION
Changes or modifications to this equipment not expressly approved by JPS
Interoperability Solutions could void the user’s authority to operate this
equipment.
NOTICE
JPS Interoperability Solutions reserves the right to make changes to the
equipment and specifications without prior notice.
PROPRIETARY STATEMENT
The information contained in this manual is the property of JPS
Interoperability Solutions and is intended for the purchaser’s use only. It may
not be reproduced without the expressed written consent of JPS
Interoperability Solutions.
© 2019 JPS Interoperability Solutions.
JPS Interoperability Solutions
Phone: (919) 790-1011
Fax: (919) 865-1400
5800 Departure Drive
Raleigh, NC 27616
NXU-2A Operations Manual
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Table of Contents
1GENERAL INFORMATION ......................................................................................................................1-1
1.1 SCOPE...................................................................................................................................................1-1
1.2 DESCRIPTION ........................................................................................................................................1-1
1.2.1 NXU General...................................................................................................................................1-1
1.2.2 NXU-2A Description .......................................................................................................................1-1
1.3 NETWORK DETAILS ..............................................................................................................................1-2
1.4 APPLICATIONS ......................................................................................................................................1-3
1.5 SPECIFICATIONS....................................................................................................................................1-4
1.6 EQUIPMENT AND ACCESSORIES SUPPLIED ............................................................................................1-5
1.7 OPTIONAL EQUIPMENT -NOT SUPPLIED ...............................................................................................1-5
2INSTALLATION..........................................................................................................................................2-1
2.1 GENERAL..............................................................................................................................................2-1
2.2 UNPACKING AND INSPECTION...............................................................................................................2-1
2.3 RESHIPMENT OF EQUIPMENT ................................................................................................................2-1
2.4 INSTALLATION OVERVIEW....................................................................................................................2-2
2.5 INSTALLATION CONSIDERATIONS .........................................................................................................2-3
2.5.1 Internal Configuration ....................................................................................................................2-6
2.6 POWER REQUIREMENTS........................................................................................................................2-7
2.7 INSTALLATION CHECKLIST ...................................................................................................................2-7
2.8 REAR PANEL ADJUSTMENTS AND CONNECTORS...................................................................................2-7
2.8.1 DC Input Connector, J6 ..................................................................................................................2-7
2.8.2 Audio Level Adjustment Potentiometers and Input Test Point ........................................................2-8
2.8.3 Connection to Radio or Other Four-Wire Device (J7)....................................................................2-8
2.8.4 Network Connection, J3..................................................................................................................2-8
2.8.5 Serial Port Connection, J4..............................................................................................................2-9
2.8.6 Connecting Equipment and Computers to an NXU-2A...................................................................2-9
3CONFIGURATION......................................................................................................................................3-1
3.1 GENERAL..............................................................................................................................................3-1
3.2 CONFIGURATION DETAILS ....................................................................................................................3-1
3.3 SERIAL PORT CONFIGURATION.............................................................................................................3-1
3.3.1 Configuration Using an RS-232 Terminal Program.......................................................................3-2
3.3.2 Command Summary ........................................................................................................................3-4
3.3.3 Setting Unit IP Address...................................................................................................................3-5
3.3.4 Setting Unit Subnet Mask and Gateway Address ............................................................................3-5
3.3.5 Using DHCP to Assign IP Parameters ...........................................................................................3-5
3.3.6 Setting VoIP Port (Optional)...........................................................................................................3-5
3.3.7 Client/Server Selection....................................................................................................................3-6
3.3.8 COR and VOX Settings ...................................................................................................................3-6
3.3.9 Duplex Setting.................................................................................................................................3-6
3.3.10 VOX Hang Time..............................................................................................................................3-7
3.3.11 COR Inhibit Time............................................................................................................................3-7
3.3.12 Serial Port Settings .........................................................................................................................3-7
3.3.13 Voice Compression Settings............................................................................................................3-8
3.3.14 Security Settings..............................................................................................................................3-8
3.3.15 Ethernet MAC Address....................................................................................................................3-8
3.3.16 Command Port................................................................................................................................3-9
3.3.17 Input Level Boost +20db.................................................................................................................3-9
3.3.18 TX Delay .........................................................................................................................................3-9
3.3.19 RX Delay .........................................................................................................................................3-9
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iv Interoperability Now!
3.3.20 VMR.................................................................................................................................................3-9
3.3.21 VOX and VMR Sensitivity Adjustments ...........................................................................................3-9
3.3.22 Restoring Factory Defaults .............................................................................................................3-9
3.4 NETWORK MANAGEMENT:SNMP SUPPORT .......................................................................................3-10
3.5 COMMUNICATIONS MODE...................................................................................................................3-11
3.5.1 Store Setup Changes with SAVE Command ..................................................................................3-12
3.5.2 NXU-2A Configuration Using the NXU-2A Setup Utility..............................................................3-12
3.6 NETWORK CONFIGURATION................................................................................................................3-15
3.7 I/O DESCRIPTIONS..........................................................................................................................3-15
3.7.1 Audio Input....................................................................................................................................3-16
3.7.2 Audio Input Test Point...................................................................................................................3-16
3.7.3 Audio Output .................................................................................................................................3-16
3.7.4 COR Input......................................................................................................................................3-16
3.7.5 AUX Inputs....................................................................................................................................3-16
3.7.6 PTT Output....................................................................................................................................3-16
3.7.7 AUX Outputs..................................................................................................................................3-16
4OPERATION.................................................................................................................................................4-1
4.1 GENERAL ..............................................................................................................................................4-1
4.2 FRONT PANEL INDICATORS...................................................................................................................4-1
4.2.1 Power LED......................................................................................................................................4-1
4.2.2 Link Active LED ..............................................................................................................................4-1
4.2.3 Channel Active LED........................................................................................................................4-1
4.2.4 Audio Input LED..............................................................................................................................4-1
4.3 REAR PANEL CONNECTORS,ADJUSTMENTS AND LEVEL POTENTIOMETERS .........................................4-1
4.4 NXU-2AOPERATION ...........................................................................................................................4-1
4.4.1 Operation at Power-Up...................................................................................................................4-2
4.4.2 Input/Output Level Adjustments ......................................................................................................4-2
4.4.3 COR Input Description....................................................................................................................4-2
4.4.4 RS-232 Serial Data..........................................................................................................................4-2
4.4.5 Auxiliary I/O....................................................................................................................................4-3
4.5 CONTROLLING CONNECTIONS...............................................................................................................4-3
4.5.1 Serial or Telnet Control...................................................................................................................4-3
4.5.2 Web Browser Control......................................................................................................................4-4
4.6 SECURITY..............................................................................................................................................4-5
4.6.1 Password Setting .............................................................................................................................4-5
4.6.2 Web Access with Password Protection............................................................................................4-6
5NXU-2A TROUBLESHOOTING................................................................................................................5-1
6NXU-2A FAQ (FREQUENTLY ASKED QUESTIONS)...........................................................................6-1
6.1 GENERAL ..............................................................................................................................................6-1
7THEORY OF OPERATION........................................................................................................................7-1
8INDEX............................................................................................................................................................8-1
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List of Figures
FIGURE 1-1 NXU-2ABASIC BLOCK DIAGRAM...................................................................................................1-2
FIGURE 1-2 SIMPLE NXU-2ARADIO SYSTEM ....................................................................................................1-3
FIGURE 2-1 OUTLINE DIMENSIONS..........................................................................................................................2-4
FIGURE 2-2 CONTROL AND CONNECTOR LOCATIONS..............................................................................................2-5
FIGURE 2-3 NXU-2A INTERNAL VIEW ...................................................................................................................2-6
FIGURE 2-4 DTE VERSUS DCE SERIAL CABLES...................................................................................................2-10
FIGURE 3-1 MTTTY TERMINAL SCREEN................................................................................................................3-2
FIGURE 3-2 NXU-2A SETUP SCREEN....................................................................................................................3-12
FIGURE 3-3 NXU-2A TERMINAL SCREEN.............................................................................................................3-13
FIGURE 3-4 NXU-2A HISTORY SCREEN ...............................................................................................................3-14
FIGURE 3-5 NETWORK CONFIGURATION SCREEN..................................................................................................3-15
FIGURE 4-1 NXU-2A CONNECTION MANAGEMENT SCREEN ..................................................................................4-4
FIGURE 4-2 NETWORK PASSWORD DIALOG............................................................................................................4-6
List of Tables
TABLE 1-1 SPECIFICATIONS...............................................................................................................................1-4
TABLE 1-2 EQUIPMENT AND ACCESSORIES SUPPLIED .................................. ERROR!BOOKMARK NOT DEFINED.
TABLE 1-3 OPTIONAL EQUIPMENT -NOT SUPPLIED ..................................... ERROR!BOOKMARK NOT DEFINED.
TABLE 2-1 BASIC INSTALLATION CHECKLIST....................................................................................................2-7
TABLE 2-2 NXU-2APINOUT (J7)......................................................................................................................2-8
TABLE 2-3 J4 SERIAL PORT PINOUT ..................................................................................................................2-9
TABLE 5-1 TROUBLESHOOTING .........................................................................................................................5-1
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vi Interoperability Now!
Glossary
Glossary
COR
Carrier Operated Relay
A signal from a receiver that gives a positive indication
that a carrier or signal is being received and that the
receiver is unsquelched. It has the same function as
Carrier Operated Squelch (COS).
COS
Carrier Operated
Squelch
See COR.
DHCP
Dynamic Host
Configuration Protocol
A method of automatically assigning an IP address to an
Ethernet device at startup time. This method conserves
IP addresses in networks where devices do not stay
connected permanently.
DSP
Digital Signal Processor
A type of microprocessor, which is optimized for signal
processing functions.
IP
Internet Protocol
A protocol designed to allow communications between
computers on different networks.
LAN
Local Area Network
A group of computers and associated devices that share a
common communications line, typically within a small
geographic area.
PTT
Push-to-talk
A signal to a radio transmitter, which controls the actual
transmission of radio frequency energy over the air. Also
called a keyline.
TCP
Transmission Control
Protocol
An additional layer to the Internet Protocol, which
ensures delivery of packets, sent across the network. It
can handle situations such as lost packets or packets
arriving out of order.
UDP
User Datagram Protocol
An additional layer to the Internet Protocol which does
not ensure delivery of packets but which offers much
lower transmission overhead than TCP.
VoIP
Voice over Internet
Protocol
Also called Voice over Packet (VoP), a method of
sending voice communications across a digital network.
WAN
Wide Area Network
A network, which is spread out over a wider area, such
as around a city or state. It may include other public or
shared networks.
Interoperability Now!
1General Information
1.1 Scope
This instruction manual provides the information necessary to install and operate the NXU-2A
Network Extension Unit.
1.2 Description
1.2.1 NXU General
NXU stands for Network Extension Unit. NXU units connect communications equipment to a
digital network using VoIP (Voice over Internet Protocol) technology. NXU units use JPS’
proprietary technology, embodied in a family of hardware and software products that enable
voice communications devices to be interconnected via a network across the room or around
the world. VoIP is a means of digitizing voice signals and transmitting them over a digital
network, such as a LAN, WAN, or even the Internet itself.
1.2.1.1 Advantages of NXU Technology
➢Enables the design of low cost, extremely flexible radio communications networks.
➢Multiplexes voice audio and data over a standard Ethernet network.
➢Uses existing network infrastructure eliminating the need for leased lines and
microwave sites.
➢Eliminates the requirement for pilot tones and other in-band signaling.
➢Facilitates centralized control of a communications network from a single computer.
1.2.2 NXU-2A Description
The NXU-2A is intended for use with radio communications consoles, communications radios,
and JPS products such as the ACU-1000 Interconnect Unit. A general-purpose stand-alone
device interfaces full duplex audio, one RS-232 port, and three status bits onto an Ethernet
network. A pair of NXU-2As can form a simple system that creates a transparent
communications link between the two. The NXU-2A at one end (usually the equipment end) is
the server; the one at the other end (usually the operator end) is the client. The audio, RS-232,
and status bits are transparently transferred between the server and the client.
Any NXU-2A can be set up as a server or as a client depending on system needs. The RS-232
interface allows for different baud rates between the server and the client.
The NXU-2A monitors its network connection and adjusts its parameters automatically to
provide optimum performance under varying network conditions. Front panel indicators
display the unit’s status. Initial configuration is done through the NXU-2A’s serial port, but
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following this initial setup, a standard web browser can be used over the network to view and
change the unit’s settings and also to perform diagnostic tests.
Designed for years of continuous operation in mission-critical applications and remote
locations, the NXU-2A has no moving parts and requires no periodic shutdown or maintenance.
Start up upon power on is typically 5 seconds.
1.3 Network Details
The NXU-2A is a 10/100BASE-T Ethernet device and each unit has a unique Ethernet address
and an RJ-45 physical interface jack. A 10/100BASE-T device operates at either 10 or 100
Mbps and interconnects to an Ethernet hub or switch using standard CAT 5 twisted pair cable,
also known as UTP. The maximum cable length between an NXU-2A and its hub port is 100
meters. With the right connective equipment (recommended or supplied by JPS), the NXU-
2A’s Ethernet port can be linked with virtually any LAN, WAN, or the Internet, no matter
which topology or cabling system is in use.
Audio In
Audio Out
RS-232
COR
PTT
AUX In
AUX Out
Ethernet
NXU-2
Figure 1-1 NXU-2A Basic Block Diagram
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1.4 Applications
Figure 1-2 below illustrates a basic NXU-2A application in which a communications
transceiver is connected via a network to a remote audio console. The transmit/receive audio
and PTT/COR signals are transported digitally across the network and appear at the other end.
The network data transfer is transparent to the user, and the operator at the audio console can
use the radio as if it were located right beside him.
Audio
Console NXU-2 NXU-2 Transceiver
LAN/WAN
Audio Audio
PTT/COR PTT/COR
Figure 1-2 Simple NXU-2A Radio System
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1.5 Specifications
Table 1-1 Specifications
RX Audio Input
Input impedance
Balanced 47k ohms, transformer coupled.
Input Level
Incoming signals adjustable from –30 to +11 dBm to set 0 dBm nominal input;
+15 dBm clipping. +20 dB boost configurable
Frequency Response
10 Hz to 3600 Hz +/- 2dB.
TX Audio Output
Output Impedance
Unbalanced 10 ohms, AC Coupled.
Output Level
Adjustable from –30 to +11 dBm, 0 dBm nominal factory default; +15 dBm
clipping into a 600 ohm load.
Frequency Response
10 Hz to 3350 Hz +/- 2dBm.
Distortion
0.5% or less (excepting Vocoder).
COR & AUX Input
Input impedance
47k ohm pull-up to +5V.
Polarity
COR: Selectable active low or active high; AUX Inputs: Active low.
Threshold
+2.5V nominal.
Protection
Up To + 100 VDC.
PTT and AUX Output
Output Type
Open drain, 47k ohm pull-up to +5V.
Maximum Sink Current
100 mA.
Max Open Circuit Voltage
+60 VDC.
Serial Interface
Interface Type
RS-232, Asynchronous, Full Duplex.
Baud Rates
300, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200 bps.
Connector
DB-9 Male, Standard PC/AT DCE Pinout.
Network Interface
Interface Type
10/100BASE-T Ethernet, 10 or 100 Mbps; RJ-45 Connector.
Protocols
Audio and status-UDP, RS-232- TCP.
Audio Vocoder
Selectable, 13, 16, 24, 32, or 64 Kbps data rate.
General/Environmental
Programming/Configuration
Web, Telnet, or RS-232 Interface.
Front Panel
Power, Link Active, Channel Active, and Audio Level LEDs.
Rear Panel
Audio/Data (DB15 Female), Serial, Network, and Power Connectors.
Input Power (12 VDC Nom)
+11 to +15 VDC @ 0.5A max. Wall cube supplied operates on 100-240 VAC.
Power Connector
Coaxial Jack, 2.5 mm ID, 5 to 5.5 mm OD; Center Pin Positive; Reverse
Polarity Protected.
Size and Weight
1.4” H x 8”W x 6.8”D (3.55 x 20.3 x 17.3 cm). 1.1 lbs. (0.5kg).
Temperature
Operating: -20 to +60 degrees C. Storage: -40 to +85 degrees C.
Humidity
Up to 95% @ 55 degrees C.
Regulatory Compliance
FCC part 15
Emissions
CE/TUV
Emissions, Immunity and Safety for Europe, USA, Canada
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1.6 Equipment and Accessories Supplied
Table 1-2 Equipment and Accessories Supplied
NXU-2A Shipping Level - JPS P/N 5041-200000
Quantity
Item
JPS P/N
1
NXU-2A Final Assembly
5041-201000
1
DC Power Supply [100 to 240 VAC, 47-63 Hz to +12 VDC, 500 mA]
1620-120600
1
Accessory Kit
5000-600150
Consisting of:
Qty Part Number Description
1 0313-070000 Network Cable, 6 ft.
1 0313-080000 RS-232 Serial Cable, 6 ft.
1 0313-080515 Audio Crossover Adapter
1.7 Optional Equipment - Not Supplied
Table 1-3 Optional Equipment - Not Supplied
Description
JPS P/N
Operation & Maintenance Manual, printed and bound
Note: This manual may be downloaded from the jpsinterop.com website at no cost
5041-200200
Generic Radio Interface Cable; unterminated at radio end; 15 ft.t
5961-291115
Interface cables for a very wide range of commercial radios are available for purchase.
Email JPS or consult the JPS Interoperability Solutions website for a listing:
Email: sales@jpsinterop.com / support@jpsinterop.com
www.jpsinterop.com
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2-1
2Installation
2.1 General
This section provides the instructions for unpacking, inspection, installation and set-up. Also
included are directions for reshipment of damaged parts or equipment.
2.2 Unpacking and Inspection
After unpacking the unit, retain the carton and packing materials until the contents have been
inspected and checked against the packing list. If there is a shortage or any evidence of
damage, do not attempt to use the equipment. Contact the carrier and file a shipment damage
claim. A full report of the damage should also be reported to the JPS Customer Service
Department. The following information should be included in the report:
➢Order Number
➢Equipment Model and Serial Numbers
➢Shipping Agency
➢Date(s) of Shipment
The JPS Customer Service Department can be reached by phone at (919) 790-1011, by fax at
(919) 790-1456. Upon receipt of this information, JPS will arrange for repair or replacement of
the equipment.
2.3 Reshipment of Equipment
If it is necessary to return the equipment to the manufacturer, a Returned Material
Authorization (RMA) number must first be obtained from JPS. This number must be noted on
the outside of the packing carton and on all accompanying documents. When packing the unit
for reshipment, it is best to use the original packaging for the unit; if this is not possible, make
sure that adequate packing material is used to prevent excessive shocks during transport and
handling.
Shipment should be made prepaid consigned to:
JPS Interoperability Solutions
Customer Service Department
5800 Departure Drive
Raleigh, North Carolina 27616
USA
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Plainly, mark with indelible ink all mailing documents as follows:
GOODS RETURNED FOR REPAIR
Mark all sides of the package:
FRAGILE - ELECTRONIC EQUIPMENT
Inspect the package prior to shipment to be sure it is properly marked and securely wrapped.
2.4 Installation Overview
NOTE: NXU-2A installation requires knowledge of Ethernet network
fundamentals as well as a basic understanding of Internet Protocol (IP). As with
any network-connected device, improperly configuring and installing the NXU-
2A could disrupt proper network operation. Please seek the assistance of your
network administrator or other knowledgeable person if you are unsure about
how your network is configured.
Six steps are needed to properly install the NXU-2A. These steps are:
1. Determine the IP address, subnet mask, and (if applicable) the gateway address for
the unit. You may have to contact the network administrator for your organization to
obtain this information.
NOTE: Operation of the NXU-2A is not possible without the information
requested above.
2. Provide the proper primary power for the unit.
NOTE: Use only the Class 2 power supply provided with the equipment.
REMARQUE: Utilisez seulement la Class 2 de la generation electrique qui est
inclus avec l'equipement.
3. Interconnect the unit with the communications system via the NXU-2A's rear panel
connectors. J7 provides the audio and control lines necessary to interface the NXU-
2A to your audio equipment.
4. Configure the unit’s operational parameters per Sections 3.2 Serial Port
Configuration through 3.6 Network Configuration.
5. Connect the unit to your Ethernet network using the supplied Ethernet cable per
Section 2.8.4 Network Connection, J3
6. Set the input and output audio levels per Section 4.4.2 Input/Output Level
Adjustments.
The NXU-2A is then ready to use.
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2.5 Installation Considerations
Careful attention to the following installation suggestions should result in the best unit/system
performance. Figure 2-1 provides overall unit dimensions.
The NXU-2A must be installed in a structure that provides both protection from the weather
and assurance of ambient temperatures between -10 and +55 degrees C. Since the unit is
neither splash proof nor corrosion resistant, it must be protected from exposure to salt spray.
When the unit is mounted in a cabinet with other heat-generating equipment, the use of a rack
blower is suggested to keep the cabinet interior temperature rise to a minimum.
NOTE: If the NXU-2A is installed in a high RF environment such as repeater
system or other transmitter site, it is recommended that all cable assemblies be
individually shielded, with the shield grounded to the ground pin on the terminal
block for that module. For all D-subminiature connector cable assemblies,
cable shields should be connected to connector shells so that they make
contact with the grounded D-subminiature connector shells on the NXU-2A.
NOTE: For the DC input, the plug is the equipment disconnect device.
REMARQUE: Pour deconnecter le DC, retirez la prise qui est couramment
connecte a l'equipement.
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2-4 Interoperability Now!
Figure 2-1 Outline Dimensions
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Figure 2-2 Control and Connector Locations
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2.5.1 Internal Configuration
The illustration below shows the NXU-2A with its top cover and rear panel removed. There is
normally no reason to remove the top cover, as the NXU-2A has no internal user-serviceable
configuration controls.
Figure 2-3 NXU-2A Internal View
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2.6 Power Requirements
The NXU-2A is designed to operate from a nominal +12V DC supply. The unit will meet all
of its specifications over a voltage range of +11 to +15 VDC and will be damaged by a DC
source that delivers a constant (non-transient) DC voltage above this range. The DC power
consumption is 500 mA maximum. The AC adapter provided with the unit meets these
specifications.
NOTE: Use only the Class 2 power supply provided with the equipment.
REMARQUE: Utilisez seulement la Class 2 de la generation electrique qui est
inclus avec l'equipement.
The NXU-2A is a microprocessor-controlled device. As with any such equipment, a very short
loss of power can cause operational problems and/or cause the unit to reset. The
communications link will be inoperable during the reset period. JPS recommends the NXU-2A
and associated equipment be connected to an AC power source that utilizes an uninterruptible
power system (UPS). If the overall site does not have UPS capability, the NXU-2A should be
plugged into a smaller UPS, such as those used for personal computer systems
2.7 Installation Checklist
Table 2-1 Basic Installation Checklist
Determine NXU-2A network parameters
such as IP address, subnet mask, and
gateway address.
You must assign these values. If you are not sure
how to determine these values, see the network
administrator for your organization.
Provide suitable power for the device.
See section 2.6 Power Requirements.
Make interconnections.
See Section 2.8.2 Audio Level Adjustment
Potentiometers and Input Test Point for External
Interconnect Information.
Configure NXU-2A parameters.
See Section 3 Configuration.
Adjust audio levels.
See Section 4.4.2.
2.8 Rear Panel Adjustments and Connectors
Refer to Figure 2-2 for a view of the NXU-2A Rear Panel. All rear panel connectors and
adjustment potentiometers are explained in the section below, starting at the left side of the
panel.
2.8.1 DC Input Connector, J6
The NXU-2A operates on a nominal +12 VDC. The power is applied through J6 via the “Wall
Cube” AC adapter provided with the unit.
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2-8 Interoperability Now!
2.8.2 Audio Level Adjustment Potentiometers and Input Test Point
A test probe may be inserted into the test point to measure the level of the incoming audio. See
Section 4.4.2 for input and output audio level setting instructions.
2.8.3 Connection to Radio or Other Four-Wire Device (J7)
The interface between the NXU-2A and associated radio or other audio device is made via J7
(Audio/Control) on the rear panel. J7 is a female DB-15 connector.
Note: an Audio Crossover Adapter, part number 0313 080515 is included with the NXU-2A.
This DB-15 male to DB-15 female adapter allows the use of radio cables developed specifically
for the JPS ACU-1000 Intelligent Interconnect system to be used with the NXU-2A. It provides
a crossover of transmit and receive audio as well as COR and PTT control signals. You only
need this adapter if you are planning to connect an NXU-2A to a radio and you are using a
cable specifically designed to connect an ACU-1000 to that radio. The adapter makes the
NXU-2A audio connector pinout match the one found on the ACU-1000. If you are wiring your
own cable, or if you are connecting the NXU-2A directly to an ACU-1000 then you don’t need
the Audio Crossover Adapter.
Table 2-2 NXU-2A Pinout (J7)
PIN
Signal
Description
1
Ground
Ground connection.
2
Not used.
3
/AUX In 0
Auxiliary Input 0 - Active low.
4
/AUX Out 0
Auxiliary Output 0 - Active low.
5
Ground
Ground connection.
6
Audio Input
Balanced audio input.
7
Analog Ground
Analog ground.
8
Audio Output
Unbalanced Audio output.
9
Not used.
10
/AUX In 1
Auxiliary Input 1 - Active low; general purpose.
11
/AUX Out 1
Auxiliary Output 1 - Active low; general purpose.
12
/COR Input
Input from radio COR, programmable active high or
low.
13
/PTT Out
Output to radio PTT, active low, open drain.
14
Audio Input
Balanced audio input.
15
Analog Ground
Analog ground.
2.8.4 Network Connection, J3
The NXU-2A is connected to the Ethernet network via rear panel connector J3 using a standard
RJ-45 Ethernet Patch Cable (non-crossover). A six-foot long cable is included with the unit.
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