Axnes PNG BST30 User manual

Axnes AS
Document number
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Date
AX-PNG-UMAN-2017
Issue C
2020-Jul-09
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PNG BST30/35 Base Station
Operation Manual
Document number:
AX-PNG-UMAN-2017
Revision:
Issue C
Date:
2020-Jul-09

Axnes AS
Document number
Revision
Date
AX-PNG-UMAN-2017
Issue C
2020-Jul-09
Page 1-2
Revision history
Revision
Date
Description
Issue A
2020-02-12
First release of document
Issue B
2020-03-20
Minor editorial updates to menu inconsistency and change from
line 1 and 2 to line 0 and 1 nomenclature
Issue C
2020-07-09
Updated with FCC reference

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Table of contents
SECTION 1: PNG SYSTEM................................................................................................1-5
1.1 Radio ................................................................................................................... 1-6
1.2 BST3x.................................................................................................................. 1-6
1.3 Portable install...................................................................................................... 1-7
1.4 Charging .............................................................................................................. 1-7
1.5 Headset................................................................................................................ 1-8
1.6 Identification of article........................................................................................... 1-8
1.7 Document References.......................................................................................... 1-8
SECTION 2: OPERATION ..................................................................................................2-1
2.1 Groups................................................................................................................. 2-1
2.2 Configurations...................................................................................................... 2-1
2.2.1 Encryption..................................................................................................... 2-2
2.3 General UI and outline ......................................................................................... 2-3
2.4 Power on/off......................................................................................................... 2-4
2.5 Noise cancelling................................................................................................... 2-4
2.6 Microphone detect................................................................................................ 2-4
2.7 Power on/off......................................................................................................... 2-5
2.8 Display indications ............................................................................................... 2-5
2.9 Adjusting headset volume .................................................................................... 2-8
2.10 VOX / PTT mode.................................................................................................. 2-8
2.11 VOX sensitivity..................................................................................................... 2-8
2.11.1 Configuring the VOX Min and VOX Max level ............................................... 2-9
2.12 Key lock ............................................................................................................... 2-9
2.13 Menu.................................................................................................................. 2-11
2.13.1 Advanced menu.......................................................................................... 2-12

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2.13.2 Install menu................................................................................................. 2-16
2.14 Audio feedback .................................................................................................. 2-18
2.15 Error conditions.................................................................................................. 2-19
2.16 Trouble shooting ................................................................................................ 2-19
SECTION 3: TECHNICAL DATA.........................................................................................3-1
3.1 Technical data for BST30/35................................................................................ 3-1
3.1.1 Operation...................................................................................................... 3-1
3.1.2 Power supply ................................................................................................ 3-1
3.1.3 Line interface 0 and 1.................................................................................... 3-1
3.1.4 Headset interface.......................................................................................... 3-2
3.1.5 Connectors.................................................................................................... 3-2
3.1.6 Radio characteristics..................................................................................... 3-2
3.1.7 Dimensions BST30/35................................................................................... 3-2
3.1.8 Material......................................................................................................... 3-2
3.2 BST30/35 Connector pinout................................................................................. 3-3
SECTION 4: RECOMMENDED MAINTENANCE AND STORAGE........................................ A
SECTION 5: ACCESSORIES................................................................................................ B
SECTION 6: QUALIFICATIONS............................................................................................D
SECTION 7: ABBREVIATIONS............................................................................................. E

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Section 1: PNG System
Axnes AS has delivered the Polycon system to the rotary wing Search and Rescue segment
for decades. The system is widely adopted in this segment. The PNG system is based on the
functionality in the previous system, but enhances the functionality and performance based
on user feedback.
The PNG system incorporates the following main features:
•Wireless extension of aircraft intercom system with significant range and robustness.
•Full duplex operation.
•Uninterrupted communication.
•Support for keying of aircraft installed radios from the handheld.
•Support for multiple communication groups.
•Automatic microphone recognition on handhelds.
•Integrated Microphone for Patient/Casualty communication in the handheld.
•Versions of handhelds are IP68 waterproof down to a depth of 3 meters.
•Active noise reduction on microphone inputs giving excellent audio quality and VOX
performance in high/extreme noise environments.
•Adaptive NIVOX (Axnes patented VOX), monitoring ambient noise environment and
minimizing the effect of false triggers, and consequently noise flooding of intercom.
•GPS homing of handheld radios in the aircraft, on control panel and possible
integration with map systems.
•AIS-SART compatible device location beacon in handheld.
•Support for mute and broadcast from aircraft side.
•Intercom operation in UHF band 397-470MHz.
•Handheld support for maritime VHF band for ship communication.
•Flexible intercom interface, supporting high and low impedance systems.
•All components available in NVG friendly versions.
Note: There are handhelds with different combinations of the following features:
Waterproofing, GPS, AIS, VHF, Bluetooth and internal speaker.
The PNG system enables wireless communication inside and outside the aircraft. The
system is very capable due to its robustness, range and noise reduction capabilities, as well
as interception free communication between the entire crew.
The PNG system consists of one base station and one or more handheld rechargeable
radios, chargers for the handhelds, as well as an optional control panel connected to the
base station. The PNG Base Station and Control Panel are installed in the aircraft and
supplied with power from the aircraft system.
The PNG handhelds implement functionality to suppress surrounding noise, and to secure
optimal voice activation performance. They implement functionality to connect to the PNG
Base Station in the helicopter (intercom mode), as well as functionality to communicate
directly with other PNG handhelds, or handheld to other radios (direct mode).
The handheld radios are designed to be mechanically robust and the MP50 handheld radio is
waterproof down to a depth of 3 meters to withstand extreme operating scenarios typically
experienced in a SAR and multirole-configured aircraft.

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Through the handheld internal microphone, the system enables communication with the
survivor/ground rescue party without helmet removal.
Depending on the configuration and part number, the handhelds are equipped with a GPS
receiver. The position of the handheld device may be polled by the PNG Base Station and
presented on the PNG Control Panel in the aircraft.
The PNG Base Station is typically connected to the aircraft ICS and may support multiple
connection points for audio and can deliver a PTT signal to other systems.
1.1 Radio
The PNG system operates a wireless link between the PNG Base Station and the handheld
radios in the UHF band. Exact frequency configuration is done at production, based on
customer input to available frequencies and bandwidth in the region they are to be operated
in. The PNG system will normally be configured within a 10 MHz band in the frequency range
397 to 470 MHz The PNG Base Station will support the full 397 to 470 MHz range
(depending on the antenna installation in the aircraft), while the handhelds support 10 MHz
bands through the 397 to 470 MHz band, depending on the installed antenna. Antennas are
available through the band.
The wireless link is a single frequency, duplex, interception free, digital radio link.
The handheld radios will operate at an output power of up to 400mW using a license specific
frequency allocation.
The PNG system will not set any limit to the number of simultaneous receivers, but the
number of simultaneous transmitters is limited by the available bandwidth and allocated
timeslots. The PNG system allows up to three simultaneous transmitting handhelds.
The handheld radios support Maritime VHF mode, and channels can be configured in the
156-162MHz band.
1.2 BST3x
The PNG BST30 (non battery operated) and BST35 (battery operated) base stations are
intended for carry on or ground support equipment and as such carrying limited aircraft
qualifications. The system can be connected to the aircraft or vehicle through preinstalled
provisions or through existing headset in/outs.
The BST30/35 PNG Base station is compatible with all existing PNG handsets such as MP30
and MP50 (requires rel 2.13 or newer handset software). The BST30/35 is a portable version
of the PNG BST50 with a reduced set of interfaces and functionality. The BST 30/35
supports the following interfaces:
•28VDC power in (designed MIL-STD-1275 compliant)
•2xIntercom connection supporting Hi and low impedance systems
•1xPTT out to intercom
•RS232/NMEA position data reported from connected PNG handsets
•1xheadset connection
•12VDC power out
•CAN bus interface (legacy)

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•1x BNC antenna port
The BST30/35 base station supports up to two voice groups, relaying through to the intercom
on two separate intercom interfaces. One of the interfaces can support a PTT line supplied
from the BST30/35 to the intercom. The PTT line can be driven by the BST30/35 triggered by
wireless communication, or it can be set up to replicate PTT keying from the handsets
(remote PTT keying).
The BST30/35 can relay position data from an GPS enabled PNG handset. The position data
can be supplied from the base station to a mission system as NMEA data, allowing tracking
of the wireless crew in moving maps, and target locking for search light and similar.
Integration between moving maps and PNG system is supported by major map system
suppliers, among others Euronav, Churchill, and Aerocomputer.
When the BST30/35 is connected to a wired intercom system, the lost intercom port can be
replicated through the BST30/35 headset port, supporting both high and low impedance
systems.
When installed in an aircraft or vehicle the antenna port can be connected to an external
antenna for optimal range and coverage.
NOTE: The antenna port shall always be terminated when the base station is powered.
Failure to terminate the antenna port may destroy the output amplifier.
1.3 Portable install
The BST30/35 is intended for a temporary/portable install and as such regarded as carry
on/ground support equipment.
The BST30 requires external power supply through nominal 28VDC, while the BST35 can be
supplied external power or operated from internal batteries allowing up to 10 hours operation.
Both versions can be equipped with a BNC antenna (different versions available from Axnes)
or connected to an external antenna mounted on the aircraft/vehicle/vessel.
The base station can be operated connected to the platform’s intercom, or it can be operated
stand alone. The Base station headset port can be operated independent of connection to
wired intercom.
The base station can be installed in a bag, or in a pouch available from Axnes. Axnes will
also have mounting brackets available.
1.4 Charging
The BST35 has integral batteries allowing up to 10 hours of continues operation. The
charging of the batteries is possible through the USB type C port, and a USB type C power
supply of minimum 45W are required (available from Axnes). The equipment can be
operated while charging. It is also possible to charge batteries from the external 28VDC
power. This option is configurable as some platforms typically will have restrictions for
charging in some operational modes.

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Charging time is expected to be around 3 hours, but depending on the surrounding
temperature, charge time may increase or be disabled. Charging is disabled below 0°C and
above 50°C. If temperature is below 10°C or above 40°C, the charge current is reduced, and
additional charging time must be expected.
1.5 Headset
The BST30/35 allows for connection of a headset to the base station. This allow for
replication of the lost intercom port or standalone operation. The headset interface is
compatible with high and low impedance headsets, and the volume setting is controlled on
the base station.
Connecting a headset will require an adapter cable (available from Axnes).
1.6 Identification of article
PNG Base Stations in the BST30 series with part numbers in the AXS-BS-D030XX* series
PNG Base Stations in the BST35 series with part numbers in the AXS-BS-D035XX* series
*Note: XX indicates any number of characters at the end of the part number string.
1.7 Document References
Ref #
Doc. Title
Doc number
[1]
PNG Installation and Interface Control Document
AX-PNG-ICD-2014

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Section 2: Operation
The PNG system consists of one PNG Base Station and one or more handheld radios. To
make all units in the PNG system interoperable, each unit must be configured with
compatible parameters. Configuration of the PNG system will imply setting of radio
frequencies, defining groups and setting scrambling or encryption parameters.
Multiple configurations may be stored on a device to support different operational modes.
The PNG system can be preconfigured from the vendor, or the configuration may be set by
the operator’s avionics department.
Ahead of flight all units in the PNG system will be set to compatible configuration. Different
types of operation may use different configurations, due to radio frequencies, group
definitions or other parameters. During operation and in flight the configuration on the PNG
Base Station is normally not changed but may be required in some special conditions. Such
conditions may be caused by radio interference, where alternative frequencies may be
required, and an alternative configuration is selected.
The operational scenario may also require different handheld configurations to be loaded in
different phases of the operation, e.g. to change group subscriptions during the mission.
Switching between the handheld configurations is done by the handheld operator by a simple
button push.
2.1 Groups
The PNG Base Station supports organizing the communication on the wireless link into
groups. Groups are a set of audio channels on the wireless link, and a set of physical audio
interfaces on the base station. The PNG system will support 2 groups depending on the
available radio resources (channel bandwidth).
The PNG Base Station will by default have audio to and from the first group on physical
audio interface 0 and the second group on physical interface 1.
The handhelds are configured to listen (receive) to one or more groups (allowing
simultaneous listening to multiple groups). Transmit is configured to one primary group
through PTT/VOX, but it is possible to configure transmit to a secondary group through
configuration and use of the secondary PTT on the handheld.
When the PNG system is set up, one or more configurations are defined, see section 2.2
Configurations.
2.2 Configurations
Both the handhelds and the PNG Base Station use configurations to control the behavior of
the devices. They can hold several configurations, with different operational parameters. A
configuration contains a minimum of the following parameters:

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•Logical name of the configuration
•Radio parameters (frequency, modulation, and channel bandwidth)
•Group subscriptions for receive
•Group subscriptions for transmit
•Configuration of remote PTT control (handheld activation of PTT from the PNG Base
Station to the intercom)
The different pre-programmed configurations can be selected at start or during mission from
the BST30/35 menu system. Typically, there will be several configurations when different
radio channels shall be made available. There can also be different configurations for
different mission types as e.g. SAR and EMS missions.
The different configurations are selected on the BST30/35 menu system with the menu
navigation buttons and identified by the logical name. When selected, all relevant parameters
are loaded.
On the handheld, the configuration is selected with the up/down arrows and identified with a
short two letter name and a long logical name (scrolling display).
Pre-programmed configurations can either be pre-ordered from the equipment vendor or
changed by a qualified equipment operator with a PC based programming tool.
2.2.1 Encryption
With the PNG system all user data are encrypted according to the AES-256 encryption
standard before they are transmitted over the air. When delivered from factory, the PNG
Base Station uses a default encryption key called “AXNES DEFAULT”. Changing this
encryption key requires the user to acquire an encryption key programming kit. Note that the
PNG Base Station and all handhelds in a system must use the same encryption key in order
to connect and communicate with each other.

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2.3 General UI and outline
The BST 30/35 supports the following interfaces:
•Circular connector for:
o28VDC external power
oIntercom connection
oPTT out to intercom
oRS232/NMEA position data
oHeadset connection
•BNC antenna port
•USB Type-C for charging and configuration
The PNG BST30/35 has a limited two letter display and 4 navigation buttons allowing limited
configuration and status control.
NOTE: The antenna port shall always be terminated when the base station is powered.
Failure to terminate the antenna port may destroy the output amplifier.
Two letter alfa numeric display
BNC antenna port
Bluetooth antenna
(future option)
USB Type-C charging
and configuration port
4x Push button for power on/off
and menu navigation
Connector for intercom
and headset integration

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2.4 Power on/off
The PNG BST30 will by default automatically turn on when power is applied either to external
power or USB power. The BST35 will be turned on when the on-button is pushed (battery
mode), or power is supplied through USB or external power lines.
The system will conduct an initial in-built test, and any errors will be displayed.
After power-up, the system loads the last used configuration and is ready for use.
The system can be turned off by a push and hold of the power off button for 3 seconds. The
system can be re-activated through a short push on the on button. At re-activation, the last
used configuration is loaded.
It should be noted that default power on and charging behavior can be controlled through
device configuration and the Axnes device configuration tool PolyConnect.
2.5 Noise cancelling
The BST30/35 implements active noise cancelling of the microphone signal from the headset
port. Noise cancelling ensures very high performance of the VOX operation, and speech
intelligibility, even in extremely noisy environments such as directly in front of a landing
helicopter or similar. The noise cancelled signal is transmitted on the radio and used in the
side tone. When using the headset port of the BST30/35 in windy environments, the
microphone should always have a windsock mounted.
2.6 Microphone detect
The BST30/35 headset port implements active microphone detection when a headset is
connected. The BST30/35 will identify the microphone type and set parameters for gain,
impedance and bias accordingly. The active microphone detect can be disabled in the menu,
and microphone type can be manually set. It is recommended to use active microphone
detect.
When a headset is detected the arrow up/down button will have the function of volume
control independent of the key lock status. When key lock is lifted the arrow up and down will
be part of the menu navigation.
Without a headset detected the arrow up/down button will follow the key lock status and be
part of the menu navigation.
The BST30/35 implements vocal audio feedback on some of the user operations if a headset
is connected to the headset port. The vocal feedback helps with the navigation and alerts the
operator of unintended operation of buttons and functions.

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The display can show two letters at a time and implements scrolling of text to display longer
strings. Most menu entries are therefore presented with a two-letter acronym, before the full
menu name is scrolled.
2.7 Power on/off
The BST30/35 is turned on by pressing the volume up/ON button. The BST30/35 will start up
in the last used configuration/mode. At power up, the configured name of the unit is
displayed. If no specific name is configured, the BST30/35 displays the last four digits of the
serial number.
The BST30/35 is turned off by holding the volume down/OFF button for 3 seconds, until a
double dash is displayed to indicate shutdown.
2.8 Display indications
Power on and active mode: When the BST30/35 is powered on and in radio on mode
(default power up state configurable) the unit will display a standby mode. The standby mode
is indicated by one blinking dot in the display, indicating that the base station transmits, and
SR search and rescue
Initial Scroll buffer

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handsets can connect to the base station. The vertical position of the dot indicates battery
status for battery operated units.
Power on and radio off mode: When the BST30/35 is powered on and in radio off mode
(default power up state configurable) the unit will display a radio off mode. With the following
symbol:
The radio on off mode can be toggled by pressing arrow up and arrow down simultaneous for
2 seconds.
Charging: When the BST30/35 is placed in a charger, the charge status is indicated with a
battery symbol and a bar indicating the charge status. The battery is animated when
charging and steady when charging is prevented (due to temperature) or battery full.
Connected to external power and not charging:
When external power is supplied through the 28V input and charging from this port is
disabled, or
USB charger of 45W is connected and charging is disabled, or
a USB charger of insufficient power is connected,
Battery low
Battery full
Battery low
Battery full

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the following symbol is displayed (only BST35):
Keylock: When operating the menu key in in keylock mode the following symbol is
displayed.
Transmit: When the BST30/35 is transmitting audio, the transmit status is indicated with a
blinking arrow pointing upwards.
Receive: When the BST30/35 is receiving, a blinking arrow pointing downwards is displayed.

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2.9 Adjusting headset volume
Depending on the headset/helmet connected to the BST30/35, the volume may be
individually set to preferred volume by using the volume up/down buttons. When the
BST30/35 is power off-on cycled, it will start up with a default volume setting.
2.10 VOX / PTT mode
The default headset mode can be set in the device configuration. If VOX is selected as
default, when a headset is connected to the BST30/35, it will by default be set to VOX mode.
It will remain in VOX mode until PTT mode is activated by pressing the PTT button on the
cable harness.
When the BST30/35 is in PTT mode, the default mode can be reactivated by disconnecting
and reconnecting the headset.
2.11 VOX sensitivity
Figure 2-1 VOX trigger level functionality
The BST30/35 has automatic VOX sensitivity. When starting the BST30/35, the VOX trigger
level starts at the VOX Min level (set in the menu). If the ambient noise level rises, the VOX
trigger level may adaptively increase. The VOX trigger level will not adapt to lower ambient
noise, and user intervention may be required. The maximum possible VOX trigger level is
limited by the VOX Max level (set in the menu).

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If the VOX trigger level is experienced too high by the user, it can be reset by either leaving
VOX mode, entering the VOX Min menu or by disconnecting/connecting the headset (Note:
By disconnecting the headset cable from the BST30/35, the water resistance is broken, thus
should NOT be done in a humid environment).
All three actions will reset the VOX trigger level to the configured VOX Min level.
The VOX trigger level can be automatically adjusted to VOX Max level by entering the VOX
Max menu.
NOTE 1: The VOX trigger level can be increased by exposing the microphone to a steady
noise, e.g. by a careful steady blow into the microphone until the sidetone disappears. The
trigger level will increase as indicated to the user by monitoring the side tone.
NOTE 2: To avoid excessive use of battery and radio capacity, it is important that the VOX
level is set to an appropriate level to avoid inadvertent transmission.
2.11.1 Configuring the VOX Min and VOX Max level
To set the correct VOX Min level, the following procedure can be followed:
•Enter the VOX Min menu.
•Tune the VOX Min level so that the VOX is triggered when your normal operational
voice level triggers a sidetone.
To set the correct VOX Max level, the following procedure can be followed:
•Enter the VOX Max menu.
•Tune the VOX Max level so that the VOX is not triggering a sidetone until you are
shouting as loud as expected in the noisiest operational condition.
•After tuning the VOX Max level, enter the VOX Min level menu to reset the trigger.
Note 1: When tuning the VOX Min or Max level, the BST30/35 is transmitting according to
selected configuration or chosen channel. It is therefore recommended to avoid VHF channel
16 when doing VOX testing/configuring.
Note 2: If setting the VOX Max to a level too low, the VOX will be triggered too often in a
noisy environment. The active VOX sensitivity will be hitting the VOX Max level and thus
never be able to go high enough.
Note 3: If setting the VOX Max to a level too high, a spike in the ambient noise level will raise
the VOX trigger level too much and thus no shouting will be loud enough to trigger the VOX.
2.12Key lock
The configuration and menu keys are protected with key lock to avoid inadvertent change of
operational mode.

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The keys are unlocked by pressing OK and MENU simultaneously.
Key lock is reactivated after 20 seconds of inactivity.
When key lock is active, the following status information is available by pressing:
Arrow up and down without headset connected: Current selected configuration/channel
Arrow up and down with headset connected: Headset volume is adjusted
Unlocking the keys will open the menu at last used menu entry.

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2.13 Menu
The first push on the MENU button will activate the last used menu entry. The configuration
up or down buttons are used to navigate the menu tree. The OK button will select the active
entry or setting, and configuration up or down will increase or reduce the value of the
selected entry. The MENU button will step one level up in the menu hierarchy.
The menu hierarchy has two levels, one top-level which may be used during operation and
one sub-level which may be used for more permanent configurations. The menu is illustrated
below:
Display Intensity: Display illumination intensity can be regulated in steps between 1-9. The
setting is persistent over a power off-on cycle. At start up the programmed default intensity is
used, and then gradual adapting to the user selected intensity over a few seconds.
Moving Map: The polling of the handsets position data can be turned on and off. The
handset position is reported as NMEA command on the NMEA port of the base station.
Standby mode
DI
Display Intensity
1-9
MM
Moving Map
On..Off
AM
Advanced Menu
Refer to chapter 2.13.1
IM
Install menu
Refer to chapter 2.13.2
CO
Select configuration
C1
Config 1
C2
Config 2

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Select configuration: The predefined configurations set up by the supplier or through the
PolyConnect tool can be selected and loaded.
2.13.1 Advanced menu
AM
Advanced Menu
HM
Headset Menu
HS
Headset
AT
Automatic
UE
Unamplified Electret
AE
Amplified Electret
CU
Custom
LD
Dynamic
AF
Audio Feedback
0-9
ME
Mic Equalizer
FT
Flat
SO
Soft
SH
Sharp