Issued on the authority of Northern Airborne Technology Ltd.
Copyright 2008
NPX136D Series Panel Mount P25 VHF Transceiver
SM68 Installation and Operation Manual
Table of Contents
Section Title Page
1. Description
1.1 Introduction 1-1
1.2 Product Description 1-1
1.3 Design Features 1-1
1.4 Specifications 1-1
1.4.1 Radio Specifications 1-1
1.4.2 Main Receiver 1-2
1.4.3 Guard Receiver (NPX136D-x70 only) 1-2
1.4.4 Transmitter 1-3
1.4.5 Physical Specifications 1-3
1.4.6 Environmental Specifications 1-4
1.5 Unit Nomenclature 1-4
1.5.1 Lighting Power 1-4
1.5.2 Special Options 1-4
1.5.3 Other Options 1-4
1.6 Accessories 1-5
2. Installation
2.1 Introduction 2-1
2.2 Unpacking and Inspection 2-1
2.2.1 Warranty 2-1
2.3 Continued Airworthiness 2-1
2.4 Installation Procedures 2-1
2.4.1 Note on Cable Routing 2-2
2.4.2 Notes on Cable Wiring and Shielding 2-2
2.4.3 Notes on Grounding 2-2
2.4.4 Cabling and Wiring 2-2
2.4.5 Antennas 2-3
2.4.6 Mechanical Mounting 2-4
2.4.7 Post-Installation Checks 2-4
2.4.8 Post Installation EMI Test 2-5
2.5 Accessories Required But Not Supplied 2-5
2.6 Installation Drawings 2-5
Installation and Operation Manual Page iii
ENG-FORM: 820-0114.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIR BORNE TECHNOLOGY LTD.
NPX136D Series Panel Mount P25 VHF Transceiver
SM68 Installation and Operation Manual
Section Title Page
3. Operation
3.1 Introduction 3-1
3.2 General Information 3-1
3.3 Controls and Indicators 3-1
3.3.1 General Features 3-1
3.3.2 Power On 3-1
3.3.3 Controls and Indicators 3-3
3.4 Displays - Normal Operating Mode 3-6
3.4.1 Display Details 3-6
3.4.2 Changing channels on the main receiver 3-8
3.4.3 Changing zones on the main receiver 3-8
3.5 Menus and Settings 3-9
3.6 Settings Menu 3-10
3.6.1 Brightness 3-10
3.6.2 Transmit Power 3-10
3.6.3 Transmit Mode 3-10
3.6.4 Squelch Mode, Analog Tones 3-10
3.6.5 Squelch Mode, Receive Digital Squelch 3-11
3.6.6 Power Up Channel 3-11
3.6.7 Squelch Setting 3-11
3.6.8 Display Menu 3-11
3.7 Channel Menu 3-12
3.7.1 Edit Main Channel Menu (Edit Main) 3-12
3.7.2 Edit Guards (Edit Guard Channel) Menu (-070 only) 3-15
3.7.3 Edit Zone Menu 3-15
3.7.4 Edit Scan Menu 3-16
3.8 Maintenance Menu 3-17
3.8.1 Master Edit Mode 3-17
3.8.2 Configuration Menu 3-17
3.8.3 Data Transfer Menu 3-19
3.8.4 Software Version 3-20
3.9 Function Mode (Fn) 3-20
3.9.1 Call Menu for Analog Channels 3-20
3.9.2 Call Menu for Digital Channels 3-22
3.10 Scanning 3-22
3.11 CTCSS and CDCSS Tone Lists 3-23
3.11.1 CTCSS Tones 3-23
3.11.2 CDCSS Tone Codes 3-24
3.12 Error Messages 3-24
Installation and Operation Manual Page iv
ENG-FORM: 820-0114.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIR BORNE TECHNOLOGY LTD.
NPX136D Series Panel Mount P25 VHF Transceiver
SM68 Installation and Operation Manual
Section 1 Description
1.1 Introduction
Information in this section consists of product description, design features and specifications for the NPX136D
Series Panel Mount P25 VHF Transceiver. All derivative product information shall be contained in the
applicable manual supplement, which may be obtained from Northern Airborne Technology Ltd. as required.
Review all notes, warnings and cautions.
1.2 Product Description
The NPX136D panel mount P25 VHF transceiver is a stand-alone radio designed for the single mission
user. It provides all the features needed to satisfy communications within the VHF high band. The
NPX136D incorporates NAT’s proven user-friendly operating system with on-line help, making it easy to
program and use. The small size makes this radio ideal for airframes where size and weight are a factor.
1.3 Design Features
The radio covers a frequency range of 136.0000 to 173.9975 MHz in 2.5/6.25 kHz increments. Each of
the 255 available channels can operate in one of three modes: wide band analog, narrow band analog or
digital P25 Phase I.
A SCAN function allows scanning of selected channels. Transmit power of either 1 watt or 10 watts is
selectable from the front panel. Simplex and semi-duplex operations are available. A guard receiver is
standard with the -070 model.
Conveniently located beside the display are separate main volume, guard volume and transmit select
switches. Easily identified along the bottom of the front panel are squelch test, channel up/down and
display controls. The aircraft dimmer bus provides control for the panel lighting.
Depth behind panel 7.02" (178.2 mm) not including connectors
Width 5.77" (146.6 mm), 4.97" behind panel
Weight 3.2 lbs. (max.)
(+1/-3 dB) / oct pre-emphasis.
300 – 500 Hz, Standard with an additional +6 dB/oct
permitted.
2500 – 3000 Hz, Standard with an additional -6 dB / oct
permitted.
750 ± 250 Hz (25 kHz BW)
Mounting Four standard Dzus-rail fasteners
Connectors One 25-pin male D-sub, with JVL locking hardware.
One 15-pin male D-sub, with JVL locking hardware
(reserved). One BNC female RF connector
Section 1 Rev: 1.00 Issue 4 Page 1-3
ENG-FORM: 800-0115.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIR BORNE TECHNOLOGY LTD.
NPX136D Series Panel Mount P25 VHF Transceiver
SM68 Installation and Operation Manual
1.4.6 Environmental Specifications
Temperature -30 C to +60 C
Altitude 50,000 feet
Humidity 95 %
Shock 6g (any axis)
RTCA/DO-160D Env. Cat. [(A4)(D1)]BAB(SBM)
1.5 Unit Nomenclature
NPX136D radios are identified as follows:
1
XXXXXXZBABA[UUX]MXXXX
NPX136D - 000
Lighting Power Special Options
1.5.1 Lighting Power
The digit in the first position of the unit suffix indicates the lighting power used.
NPX136D - 000
0 = 28 Vdc Lights
1.5.2 Special Options
The digit in the second position of the unit suffix indicates any special options installed.
NPX136D - 000
0 = No Guard installed
7 = Two channel synthesized Guard
1.5.3 Other Options
The digit in the third position of the unit suffix is currently not assigned.
NPX136D - 000
1
Vibration also qualified to DO-160C, Sec. 8, Cat. N.
Section 1 Rev: 1.00 Issue 4 Page 1-4
ENG-FORM: 800-0115.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIR BORNE TECHNOLOGY LTD.
NPX136D Series Panel Mount P25 VHF Transceiver
SM68 Installation and Operation Manual
1.6 Accessories
Installation Kit NPX-IKC
Serial Load Kit FC51-000
Consists of:
PC Serial Load (CD) NUDP-006
Data Transfer Cable FC51-001
PC Cable FC47-001
TFM138 Harness to NPX FC45-002
Section 1 ends
Section 1 Rev: 1.00 Issue 4 Page 1-5
ENG-FORM: 800-0115.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIR BORNE TECHNOLOGY LTD.
NPX136D Series Panel Mount P25 VHF Transceiver
SM68 Installation and Operation Manual
Section 2 Installation
2.1 Introduction
Information in this section consists of unpacking and inspection procedures, installation procedure s, po stinstallation checks and installation drawings for the NPX136D Series Panel Mount P25 VHF Transceiver.
Review all notes, warnings and cautions.
2.2 Unpacking and Inspection
Unpack the equipment carefully and locate the warranty card. Inspect the unit visually for damage due to
shipping and report all such claims immediately to the carrier involved. Check that all items listed below
are present before proceeding and report any shortage immediately to your supplier:
- Warranty Card
- Operators Manual
- Certificate of Conformity or Release Certification
2.2.1 Warranty
All Northern Airborne Technology Ltd. products are warranted for 2 years from date of installation by an
authorized Northern Airborne Technology Ltd. dealer, to be free of defects in workmanship or
performance. This warranty covers all materials and labour, but is exclusive of any transport to deliver the
defective unit to and from Northern Airborne Technology Ltd. or its designated warranty repair center, or
any labour to remove or re-install the defective unit in the aircraft. Contact Northern Airborne Technology
Ltd. for any questions regarding this warranty, its applicability to your units and/or for return authorization.
Northern Airborne Technology Ltd. is the final arbitrator concerning warranty administration. Units which
have been physically damaged, burned, immersed in water or otherwise abused beyond the scope of
normal use will not be considered for warranty. WARRANTY IS VOID UNLESS THE PRODUCT IS INSTALLED BY AN AUTHORIZED NORTHERN AIRBORNE TECHNOLOGY LTD. DEALER. Product
for which a warranty card is not returned shall be warranted from date of manufacture.
2.3 Continued Airworthiness
Maintenance of the NPX136D is ‘on condition’ only. Periodic maintenance of this product is not required.
2.4 Installation Procedures
Installation Notice
This product must be installed in accordance with the installation instructions provided in the latest issue
of this Installation and Operation Manual. Check the NAT Publication Index at www.northernairborne.com
for the issue status of the manual. The latest issue of the manual may be downloaded from the same
website. All risk associated with installation of this product contrary to these instructions shall be the
responsibility of the installing agency.
Section 2 Rev: 1.00Issue4 Page 2-1
ENG-FORM: 805-0118.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIR BORNE TECHNOLOGY LTD.
NPX136D Series Panel Mount P25 VHF Transceiver
SM68 Installation and Operation Manual
2.4.1 Note on Cable Routing
Do not bundle any lines from this unit with transmitter coax lines. Do not bundle any logic, audio, or DC
power lines from this unit with 400 Hz synchro wiring or AC power lines. Do not position this unit next to
any device with a strong alternating magnetic field such as an inverter or significant interference
to operation will result. In all installations, use shielded cable exactly as shown
indicated. Significant problems may result if these guidelines are not followed.
2.4.2 Notes on Cable Wiring and Shielding
All audio installations can be severely degraded by incorrect wiring and shielding, and may result in much
higher cross-talk, hum, and ground-loop interference. This should be considered when audio wiring to
and from the radio installation is performed.
2.4.3 Notes on Grounding
The case of the radio must be electrically grounded for maximum resistance to low frequency
interference. A pin on the connector (Chassis ground) is provided and must be connected by a short wire
to a clean ground, NOT jumpered to the power ground wire connection.
Refer to the aircraft structural repair manual and maintenance manual for instructions and information
pertinent to this installation.
and ground as
2.4.4 Cabling and Wiring
All wire shall be selected in accordance with the original aircraft manufacturer's Maintenance Instructions
or AC43.13-1B Change 1, Paragraphs 11-76 through 11-78. Unshielded wire types shall qualify to
MIL-W-22759 as specified in AC43.13-1B Change 1, Paragraphs 11-85, 11-86, and listed in Table 11-11.
For shielded wire applications, use Tefzel MIL-C-27500 shielded wire with solde r sleeve s (fo r shield
terminations) to make the most compact and easily terminated interconnect. Follow the connector map in
Section 2.6 as required.
Coaxial cable shall be selected in accordance with MIL-C-17 unless otherwise specified. Do not use coax
cable with PVC insulation. Teflon dielectric cable is encouraged at or above VHF frequencies or where
cable runs exceed 8 feet. Note that at VHF frequencies, cables losses due to long cable runs and tight
bends may reduce the ERP (Effective Radiated Power) by greater than 50%.
Allow 3" from the end of the shielded wiring to the shield termination to allow the connector hood to be
easily installed. Reference the interconnect drawing in Section 2.6 for shield termination details. Note that
the hood is a "clamshell" hood, and is installed after the wiring is complete. Installation cabling must allow
the radio to be easily withdrawn for disconnection and field service adjustments. Ensure an adequate
service loop in the routing of the cables. It can be a serious issue if the unit is installed with the cables so
short that the unit cannot be removed without disassembly of the surrounding structures. At least 30 cm
(1 foot) of free cable is recommended.
Maintain wire segregation and route wiring in accordance with the original aircraft manufacturers
Maintenance Instructions. Fabrication & installation of wiring harness should be in accordance with the
original aircraft manufacturer’s Maintenance Instructions or AC 43.13-1B Change 1, chapter 11, sections 5
to 13, 16 and 17. Coaxial cables shall be routed separately from existing wire bundles in the aircraft to
minimize electromagnetic coupling effects. To prevent RF interference between similar systems, it is
Section 2 Rev: 1.00Issue4 Page 2-2
ENG-FORM: 805-0118.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIR BORNE TECHNOLOGY LTD.
NPX136D Series Panel Mount P25 VHF Transceiver
SM68 Installation and Operation Manual
recommended that VHF FM coax runs be widely separated, or be made using triaxial cable, with the outer
shield bonded to the airframe at one end only (transceiver end). In communication-intensive applications,
poor cable routing and shielding may drastically compromise over-all system performance. Symptoms may
be spurious squelch opening, RFI (Radio-Frequency Interference), and garbled reception.
RF cables must be neatly terminated (solder or crimp), and tested for shorts prior to system check-out
(not while connected to the radio or antenna). Keep cable bends to a minimum at the antenna. Avoid
sharp bends in the coax cables (minimum 3" radius) to prevent severe reflections. If sharp bends are
required, use 90° elbow adapters.
Unless otherwise noted, all wiring shall be a minimum of 22 AWG, except power and ground lines, which
shall be a minimum of 20 AWG. Reference the Interconnect drawing for additional specifications. Check
that the ground connection is clean and well secured, and that it shares no path with any electrically noisy
aircraft accessories such as blowers, turn and bank instruments or similar loads. Power to this unit must
be supplied from a separate circuit breaker or fuse (fast blow), and not attached to any other circuit
breaker without additional protection. Verify that the selected circuit breaker size and wire gauge are
adequate for the installation using the techniques specified in AC43.13-1B Change 1, Paragraphs 11-47
through 11-51 and 11-66 through 11-69.
Grounding and bonding should be in accordance with the original aircraft manufacturers Maintenance
Instructions or AC 43.13-1B Change 1, chapter 11, section 15.
2.4.5 Antennas
WARNING:
To limit exposure to radio frequency fields that exceed exposure limits for
people occupying the aircraft, install the antenna such that it is mounted either
on a ground plane that is between the antenna and the occupants of the aircraft,
or further than 32 inches (80cm) from the occupants of the aircraft.
Correct antenna placement and mounting is critical in order to achieve the best possible performance. In
general, keep all antennas as widely separated as possible and clear of any large airframe obstructions.
Installation of the antenna should be in accordance with the aircraft manufacturer’s instructions for
continued airworthiness or AC 43.13-1B Change 1, chapter 11, section 15 and AC 43.13-2A chapter 3. If
possible, the antenna should be located a minimum of 12 ft from aircraft navigation receiver antennas an d
a minimum of 4 feet from aircraft communications and ELT antennas. Be careful not to choose
separations that closely approximate ¼, ½ or whole-number multiples of the navigation or
communications system wavelength.
Note: Avoid any placement that puts antennas of like frequencies close together.
Bottom mounted antennas will perform best in flight, but poorest on the ground during testing. Antennas
may be severely degraded by 'masking' effects of the fuselage or stabilizers, and generally give best
performance when bottom mounted.
To reduce interference from rotor modulation and other undesirable stimuli, any blade or whip antenna must
be surrounded by a ground plane surface (metallic, grounded material) with a radius equal to or greater than
the height of the antenna. Under the same conditions, the antenna is also much less likely to cause
interference to other aircraft systems (e.g. coupling into audio system, fluctuations in instrumentation, etc).
Poor grounding will result in severe reflected power and high levels of RFI throughout the airframe.
Section 2 Rev: 1.00Issue4 Page 2-3
ENG-FORM: 805-0118.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIR BORNE TECHNOLOGY LTD.
NPX136D Series Panel Mount P25 VHF Transceiver
SM68 Installation and Operation Manual
Avoid antenna locations that will become fouled with oil, water, fuel or dirt, as this will degrade
performance. Roof mounts (in close proximity to rotor blades) are permissible.
2.4.6 Mechanical Mounting
Installation of the transceiver should be in accordance with the aircraft manufacturer’s instructions for
continued airworthiness or AC 43.13-1B Change 1, chapter 7, sections 2 to 7 and AC 43.13-2 A, chapter 2.
Pr 35 Dzus rail or equivalent may be used.
Mounting the radio requires a Dzus rail assembly with an opening width of 5 inches (127 mm) and a front
clearance width of 5.75 inches (146.1 mm). Height requirement is 2.65" max (67.2 mm max). Refer to the
mounting drawings and unit mechanical specifications to determine proper clearance dimensions. Be
sure that adequate clearance is allowed for the cable connections to each unit.
2.4.7 Post-Installation Checks
2.4.7.1 Voltage/resistance checks
Do not attach the radio until the following conditions are met.
Check the following:
a) P1 pins <12> and <13> for +28 Vdc relative to ground.
b) P1 pins <22>, <23>, <24> and <25> for continuity to ground (below 0.5 Ω).
c) Light voltage as per table below.
Light Voltage P1 Pin # Voltage
28 Volt Models 11 28 Vdc
14 Volt Models 10 14 Vdc
5 Volt Models 10 5 Vdc
Ensure that the antenna is disconnected for the following test or erroneous readings may be obtained.
d) Radio coax connector for continuity to the antenna coax connector (shield and centre conductor),
and for open circuit from the centre conductor to ground and open circuit from the centre
conductor to the shield.
2.4.7.2 Power On Checks
a) Install the radio and power up the ship’s systems. Turn on the radio. Check the operation of all front
panel controls. Adjust brightness and volume levels as required.
b) Check all transmit and receive functions. Ensure the RX/TX status indicator lights green when the
c) Check the SCAN function.
radio is keyed to transmit and amber when receiving.
Note: You may be unable to hear the received audio if the tones do not match those set in the
radio. To avoid any confusion, tones should be set to OFF (via the settings menu) before
scanning so that all channels will be heard.
Section 2 Rev: 1.00Issue4 Page 2-4
ENG-FORM: 805-0118.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIR BORNE TECHNOLOGY LTD.
NPX136D Series Panel Mount P25 VHF Transceiver
SM68 Installation and Operation Manual
d) Check the antenna feedline at the R/T with a through-line wattmeter and suitable frequency
elements to ensure correct antenna matching. Reflected power in excess of 25% represents a
serious problem, and should be investigated carefully, or serious RFI and system interference as
well as possible radio damage may result. A VSWR measurement over 3.0:1 represe nts a
significant loss in signal power to the antenna. Check that forward power is to specifications over
Upon satisfactory completion of all performance checks, make all required log book entries, electrical
load, weight and balance amendments and other documentation as required by your local regulatory
agency before releasing the aircraft for service.
2.4.8 Post Installation EMI Test
The purpose of this test is to identify any interference that the radio may cause with existing aircraft
systems. The radio should be tested in accordance with the Installation Approval Test Procedure (see
section 2.6), and the test results documented on the record sheets.
2.5 Accessories Required But Not Supplied
Installation kit p/n NPX-IKC (crimp) is required to complete the installation. The kit consists of the following:
The NAT Part D25SV-IKC Crimp Installation Kit consists of: