Park Air Systems BT6MBS User Guide
T6M Base Station
User Guide
Handbook Part Number: 31-360T6MBS
Handbook Title: T6M Base Station User Guide
Handbook Part Number: 31-360T6MBS
Issue Number: one
Date of Issue: September 2000
Published by: Park Air Electronics
Northfields
Market Deeping
Peterborough
England
Telephone: From UK, 01778 345434
From outside UK, 44 1778 345434
Fax: From UK, 01778 342877
From outside UK, 44 1778 342877
T6M Base Station User Guide
Page 2
Amendment Record
Amendments to this User Guide, initiated by PAE, are recorded in the following table.
Amendment
Number
Incorporated
by:
Date Brief Details
Modification Record
Changes or modifications to the T6M base station that are not expressly approved by
Park Air Electronics could void your authority to operate the equipment.
Modification
Number
Modifications to the T6M base station, authorized by PAE, are recorded
in the following table.
Embodied by: Date Brief Details
T6M Base Station User Guide
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SAFETY
Warnings
[Failure to comply with warnings can result in personal injury, fire, or electric shock.]
DO NOT operate equipment at high volume levels. Hearing experts advise against continuous
q
high volume operation. If you experience ringing in your ears, reduce the volume level, or
discontinue use.
The Radio module's power amplifier circuit contains beryllium oxide that can be extremely toxic.
q
No instructions within this user guide remove any of the radio module's covers so users are not
exposed to a potential beryllium hazard. If the radio module is to be disposed of, users must be
aware of current disposal regulations regarding equipment containing beryllium.
The antenna used with this radio equipment must be installed such that the resultant radiated
q
field strength is below 10 W/m
The base station can be fitted with an optional internal battery. It is a sealed lead-acid type with a
q
² in areas normally accessible to personnel.
thixotropic electrolyte. The battery has self sealing safety vents that may release small quantities
of gas under extreme conditions. Because of this, users must ensure that the enclosure's vents
are always free from obstruction.
FEDERAL COMMUNICATIONS COMMISSION (FCC) REGULATIONS
q
This device complies with Part 15 of the FCC Rules. Operation is subject to the condition that this
device does not cause harmful interference.
q
You are required to obtain a station licence before transmitting from your base station.
q
This equipment is only licenced for operation on 25 kHz channel spacing. Operation on 8.33 kHz
channel spacing is not allowed within the USA.
q
The base station power output must not exceed the output necessary for satisfactory technical
operation taking account of local conditions and the area to be covered.
q
The base station's frequency and parameters should be checked by authorized service
personnel before use, and at least yearly thereafter.
T6M Base Station User Guide
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FOREWORD
This user guide describes the purpose, installation, and operation of the Park Air Electronics (PAE) T6M
base station. Read all instructions given in this user guide before operating the equipment.
TRADEMARKS
The following trademarks are used in this user guide.
IBM Is a registered trademark of International Business Machines.
Microsoft Is a registered trademark of Microsoft Corporation in the USA and other countries.
Windows Is a registered trademark of Microsoft Corporation in the USA and other countries.
T6M Base Station User Guide
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CONTENTS
SAFETY 4
Federal Communications Commission (FCC) Regulations 4
Foreword 5
Trademarks 5
Chapter 1 - Overview 9
About this Handbook 9
Associated Handbook 9
Introduction to the T6M Base Station 9
Facilities 10
Remote Controllers 10
Power Supplies 10
Programming the Base Station's Personality 10
Options 11
Internal Battery 11
Rack Mount Option 11
Local Monitoring of Transmitted Audio 11
Chapter 2 - Specification 13
General 13
Dimensions and Weight 14
Input Supplies 14
ac Supply 14
dc Supply 14
Optional Internal Battery 14
Receive Circuit 15
Transmit Circuit 15
Chapter 3 - Operation 17
Introduction 17
Front Panel Controls 18
Display 18
Transmit Indicator 18
Busy Indicator 18
Power Indicator 18
Microphone/Diagnostics Connector 18
Volume Control 18
External Tx Inhibit Indicator 18
Battery Indicator 18
Loudspeaker Grille 18
PRI Button 19
SQL Button 19
SELs and SELt Buttons 19
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CHs and CHt Buttons 19
SCN Button 19
VOLs and VOLt Buttons 19
Power Button 19
Switching On and Off 20
Operating the Base Station in Normal Mode 21
Selecting Normal Mode 21
Selecting a Channel Frequency 21
Transmitting and Receiving 21
Switching and Adjusting the Squelch Facility 21
Operating the Base Station in Priority Mode 23
Selecting Priority Mode 23
Selecting a Priority Channel Frequency 23
Transmitting and Receiving 23
Operating the Base Station in Scan Mode 24
Selecting Scan Mode 24
Selecting a Scan Group 24
Transmitting and Receiving 24
Programmable Options 25
Display Blanking 25
Warning Beeps 25
Key Beeps 25
Transmit Inhibit 26
Maximum Transmit Time 26
Front Panel Display for 25 kHz and 8.33 kHz Channel Spacing 26
Fault and Error Codes 28
Chapter 4 - Installation 29
Introduction 29
Unpacking 30
Setting Internal Links 30
Siting the Base Station 31
Connecting a T6M Controller to the Base Station 31
Connecting an antenna 31
Connecting the Chassis Stud to Earth 31
Connecting a microphone 32
Securing the Microphone Bracket 32
Connecting External Facilities 33
Connecting a dc Input Supply 35
Connecting an ac Input Supply 36
Connecting a PC to the Base Station 36
Chapter 5 - Programming the Base Station 37
Introduction 37
Programmable Options 39
Display Blanking 39
T6M Base Station User Guide
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Warning Beeps 39
Key Beeps 39
Hold on Scan Mode 40
Installing the Programming Software onto a Laptop, or PC 40
Creating a New Personality 40
Saving a Personality 44
Opening a Saved Personality 45
Loading a Personality into the Radio 45
Reading a Personality from the Radio 45
Printing a Personality Report 46
Chapter 6 - Spares 47
Introduction 47
List of Spares 47
Chapter 7 - Maintenance 49
Scheduled Maintenance 49
Test Equipment Required 49
Test Lead 49
Transmit Power and Frequency Accuracy Test 50
Receiver Sensitivity Check 52
Battery Replacement 52
Fault Finding 53
Replacing Modules 55
Chapter 8 - Figures 57
T6M Base Station User Guide
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Chapter 1 - Overview
This chapter gives a brief overview of the T6M base station and its facilities.
ABOUT THIS HANDBOOK
This handbook describes the Park Air Electronics (PAE) T6M Base Station. Its purpose is to provide the
information necessary for users to install, operate, and maintain the equipment to module level. To
achieve this, the handbook is divided into eight chapters as follows:
Chapter 1. Gives a brief overview of the equipment and its facilities.
Chapter 2. Provides the equipment specification.
Chapter 3. Details the equipment's controls, indicators and connectors, and provides the
operating instructions.
Chapter 4. Provides detailed installation procedures and defines all interfaces.
Chapter 5. Describes how the base station's ‘personality’ can be changed.
Chapter 6. Lists the spares available for the base station.
Chapter 7. Gives maintenance information.
Chapter 8. Contains the A3 size figures that are referred to throughout this user guide.
Associated Handbook
When reading this handbook it may be necessary to refer to the following handbook:
T6M Controller User Guide. Part number 31-3600T6MC.
INTRODUCTION TO THE T6M BASE STATION
The T6M multichannel base station provides two-way communication within the VHF aeronautical
frequency band 118 to 136.9916 MHz. The radio provides a nominal 10 watt amplitude modulated (AM)
output, and operates on both 25 kHz and 8.33 kHz spaced channel frequencies. A fist microphone, with
an integral PTT switch, is provided for transmissions; received signals are monitored through the built-in
loudspeaker.
Before use, the radio's ‘personality’ is programmed into its internal memory. The personality defines up
to 760 channel frequencies, the required operating modes, and various secondary options. Three
operating modes are available: Normal, Priority, and Scan.
Normal Mode In normal mode, any channel frequency programmed into the base station can
be selected using the front panel controls. Up to 760 channel frequencies can
be programmed into the radio's personality.
Priority Mode Priority mode allows faster access to frequently used channels. Up to 15 of the
channel frequencies that are available in Normal mode can be programmed
into the priority list.
Scan Mode If scan mode is selected, the radio scans a number of pre-defined channels
searching for a ‘busy’ one. When a busy channel is found, and depending on
the programmed options, the radio remains tuned to that channel. Up to 15
scan groups can be set up, each group containing up to 15 channel
frequencies.
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FACILITIES
A facilities connector is fitted to the base station's rear panel. It provides the following interfaces:
Audio in/out and PTT control for connection to a Voice Communication and Control System
q
(VCCS).
Audio out for connection to a tape recording system.
q
An audio operated squelch signal that allows an external ‘busy’ indication.
q
A transmit inhibit input signal. This input may be used to prevent the base station being keyed.
q
REMOTE CONTROLLERS
Up to four T6M Controllers can be connected to a base station. Each controller allows remote
transmission and reception on the frequency currently selected at the base station. Full details of the
controller are contained in the T6M Controller User Guide.
POWER SUPPLIES
The base station can operate from an ac mains supply, an external dc supply, or an internal battery (see
‘Options’ on page 11). When both an ac and a dc supply are connected, the base station operates from
the ac input; the dc input acts as a backup in case the mains fails.
PROGRAMMING THE BASE STATION'S PERSONALITY
The base station's ‘personality’ is programmed into its internal memory and defines up to 760 channel
frequencies, the required operating modes, and various secondary options. When the equipment is
received from PAE, the personality is either:
q
A personality programmed to the user's specific requirements.
or,
q
A default personality that covers the 760 channels (25 kHz spaced) available in the VHF
aeronautical frequency band. No frequencies are allocated to the priority list, and no scan
groups are set.
A programming kit is available from PAE. This allows a new personality to be programmed into the radio
at any time.
The kit comprises software loaded on a CD-ROM, and a programming lead. An IBM™ compatible
laptop, or Personal Computer (PC) running Microsoft Windows™ 95 or 98 must be available to
reprogramme the radio.
To order the programming kit, contact PAE quoting part number 70-T6MPMKIT.
T6M Base Station User Guide
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OPTIONS
Internal Battery
An internal battery can be fitted to act as a backup should the ac mains supply fail. This option may be
required when no external dc backup supply is available.
The battery is float charged from the ac supply. If the mains fails, the battery provides a minimum two
hours of operation, at 25° C, provided the duty cycle does not exceed 10%. When operating from the
internal battery, the transmit power output is reduced by up to 3 dB.
When the battery option is fitted, link JP2 on the interface module must be correctly set (see ‘Setting
Internal Links’ in the installation chapter).
Rack Mount Option
The base station is normally supplied in a free-standing desktop polymer enclosure. As an option, the
base station's chassis can be fitted in a metal enclosure suitable for 19 inch (483 mm) rack mounting.
Local Monitoring of Transmitted Audio
Normally, transmit and received audio is monitored through the base station's internal loudspeaker; this
allows a base station operator to monitor both sides of voice traffic when remote controllers are being
used. Alternatively, the equipment can be configured so that only receiver audio is monitored through the
loudspeaker.
This facility is enabled by setting link JP1 on the interface module (see ‘Setting Internal Links’ in the
installation chapter).
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Chapter 2 - Specification
Chapter 2 gives the specification of the T6M base station.
GENERAL
The general parameters of the T6M base station are listed below.
Operation Simplex VHF AM transmit and receive.
Operating modes Normal, priority, and scan.
Channel bandwidth 25 kHz and 8.33 kHz.
Frequency range (at 25 kHz) Between 118 and 136.975 MHz.
Frequency range (at 8.33 kHz) Between 118 and 136.9916 MHz.
Frequency stability ± 1.5 ppm
Channel selection In Normal mode up to 760 channel frequencies can be
programmed into the radio. The channels can have
25 kHz spacing, 8.33 kHz spacing, or a mixture of both.
Priority mode allows up to 15 of the stored channels to
be allocated to a priority list. Channel selection can then
be limited to those frequencies in the priority list.
In Scan mode, the radio can have up to 15 scan groups
each containing up to 15 channel frequencies.
Duty cycle (receive) Continuous.
Duty cycle (transmit) 25% with a maximum transmit time of 5 minutes. A
longer transmit time, or a higher duty cycle, reduces the
output power by up to 6 dB.
When the base station operates from the optional
internal battery, a duty cycle above 10% rapidly
discharges the battery (see ‘Optional Internal Battery’ on
page 14).
Operating temperature range Between -20°C and +55°C.
Storage temperature range Between -40°C and +70°C.
Humidity Can be operated in humidity up to 80%.
Cooling Fan assisted air flow. Fan turns on at approximately
40°C; the fan's speed increases as temperature
increases.
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DIMENSIONS AND WEIGHT
The dimensions and weight of the base station fitted within the standard enclosure are:
Width 446 mm.
Height 176 mm.
Depth 400 mm.
Weight 9.5 kg without battery option fitted.
11.5 kg with battery option fitted.
The dimensions and weight of the rack mounted base station are:
Width 483 mm.
Height 89 mm (2U).
Depth 423 mm.
Weight 9 kg without battery option fitted.
11 kg with battery option fitted.
INPUT SUPPLIES
The base station can operate from an ac mains supply, or an external dc input supply. When both
supplies are connected, the dc supply acts as a backup supply should the mains fail.
ac Supply
The base station requires the following ac input supply:
Input voltage Between 98 and 254 V ac at either 50 or 60 Hz.
Maximum current 2 A.
dc Supply
The base station requires the following dc input supply:
Input voltage Between 12 and 15.5 V. For maximum transmitter output
power, the dc input must be between 14 and 15.5 V.
Maximum current 9 A.
OPTIONAL INTERNAL BATTERY
An optional internal battery can be fitted to power the base station when external supplies fail. The
battery provides:
Voltage 12 V dc.
Operating time The battery provides at least two hours of operation
when the duty cycle does not exceed 10% (measured at
a working temperature of 25° C). The transmitter output
power is reduced by up to 3 dB during battery operation.
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RECEIVE CIRCUIT
The specification of the receive circuit is listed below.
Sensitivity -104 dBm at 30% modulation depth for 10 dB (S+N):N.
Selectivity 8.33 kHz spaced: <6 dB at ±3 kHz; >60 dB at ±8.33 kHz.
25 kHz spaced: <6 dB at ±8.5 kHz; >70 dB at ±25 kHz.
Intermodulation suppression >70 dB.
Spurious response suppression >80 dB.
Audio power output 2 W into 8 ohm integral speaker (<10% THD).
Distortion <10% THD for 90% modulation depth.
RF input impedance 50 ohms.
TRANSMIT CIRCUIT
The specification of the transmit circuit is listed below.
RF output power Adjustable between approximately 5 and 12 W.
Spurious <-46 dBm when more than 1 MHz from the carrier.
Harmonics <-36 dBm.
Modulation depth Up to 85%. Compression above 85% to prevent over
modulation.
RF load impedance 50 ohms.
Frequency stability ± 1.5 ppm.
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Chapter 3 - Operation
This chapter gives the instructions for operating the base station after it has been correctly installed.
Users should note that the facilities available to an operator depend on how the radio's personality has
been configured.
INTRODUCTION
The base station provides transmission and reception on any 25 kHz, or 8.33 kHz, spaced channel
frequency within the VHF aeronautical frequency band between 118 and 136.9916 MHz. However, only
those frequencies and operating modes that are pre-programmed into the radio can be selected. The
radio can be reprogrammed at any time using the supplied software. Instructions for doing this are given
in chapter 5 starting on page 37.
Three operating modes are available: Normal, Priority, and Scan. In Normal mode, any frequency
programmed into the system can be selected using the radio's front panel controls. Priority mode is
similar to Normal mode, but allows faster selection of up to 15 frequently used channels.
In Scan mode, the radio scans a number of pre-defined channels searching for a ‘busy’ one. When a
busy channel is found, and depending on the programmed options, the radio remains tuned to that
channel ready for use. Scanning can be resumed at any time.
When a T6M base station is received from PAE, the personality is either:
A personality programmed to the user's specific requirements.
q
or,
q
A default personality that covers the 760 channels (25 kHz spaced) available in the VHF
aeronautical frequency band. No frequencies are allocated to the Priority list, and no scan
groups are set.
A programming kit is available from PAE. This allows a new personality to be programmed and downloaded.
The radio does not have to be removed from its installed position to download a new personality.
Note that operation using 8.33 kHz channel spacing is not currently allowed within the USA.
The following topics are covered in this chapter:
q
Description of front panel controls and indicators; page 18.
q
Switching on and off; page 20.
q
Operating the base station in normal mode; page 21.
q
Operating the base station in priority mode; page 23.
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Operating the base station in scan mode; page 24.
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Programmable options; page 25.
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Front panel display for 25 kHz and 8.33 kHz channel spacing; page 26.
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Fault and error codes; page 28.
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FRONT PANEL CONTROLS
Display
(Figure
Priority mode, the display shows the channel frequency but alternates to show a ‘P’ every few seconds.
In Scan mode, and when the radio is scanning, the display shows Scn and the currently selected scan
group (a number between 1 and 15). When a busy channel is found, the channel's frequency is
displayed.
The display, in the event of a detected unserviceability, shows fault and error codes.
Transmit Indicator
(Figure
Busy Indicator
(Figure
squelch circuit, is received. This indicator is always lit when the squelch facility is switched off.
Power Indicator
(Figure
Power button. The front panel Power button cannot be operated unless the rear panel power switch is set
to on. Note that when the radio is switched off using the front panel Power switch, and the rear panel
switch remains at on, the internal battery (if fitted) continues to charge.
3, Item 1). In Normal mode, the display shows the currently selected channel frequency. In
3, Item 2). A red indicator that lights when the transmitter is keyed and producing power.
3, Item 3). A yellow indicator that lights when a signal, of sufficient strength to overcome the
3, Item 4). A green indicator that lights when the radio is switched on by pressing the front panel
Microphone/Diagnostics Connector
(Figure
base station. This connector will also accept a microphone/headset; the connector's pin-out is shown on
page 32.
This socket is also used to connect the base station to a laptop, or PC, so that the base station's
personality can be programmed.
Volume Control
(Figure
an integral switch: when the control is pushed in, the loudspeaker is switched on; when the control is
pulled out, the loudspeaker is switched off.
External Tx Inhibit Indicator
(Figure
the transmitter cannot be keyed on any frequency.
External Tx Inhibit is set, if required, by physically connecting pin 14 on the rear panel Facilities
connector to earth (see ‘Connecting External Facilities’ in chapter 4).
Battery Indicator
(Figure
is charging, the indicator is amber. When the battery is charged to approximately 75% of its maximum,
the indicator changes to green.
3, Item 5). A 7-pin DIN socket used to connect the fist microphone normally supplied with the
3, Item 6). A rotary control used to adjust the volume of the internal loudspeaker. The control has
3, Item 7). A red indicator that flashes when the external Tx inhibit facility is active. When active,
3, Item 8). This indicator is used only when the internal battery option is fitted. When the battery
Loudspeaker Grille
(Figure
T6M Base Station User Guide
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3, Item 9). The base station's internal loudspeaker is fitted behind this grille.
PRI Button
(Figure
selected when it is programmed into the base station's personality.
The Priority button is also used in the sequence to enter Test mode.
SQL Button
(Figure
squelch level is adjusted by using the VOLs and VOLt buttons . The Squelch button is also used in the
sequence to enter Test mode.
SELs and SELt Buttons
(Figure
In Normal mode, the select buttons skip through the programmed channel frequencies 10 channels at a
time. These buttons are used in conjunction with the CHs and CHt buttons to select the required
channel frequency.
In Priority mode, these buttons are used to select the required Priority channel frequency.
In Scan mode, these buttons are used to select the required scan group.
These buttons are also used in the sequence to enter Test mode and as a coarse adjustment when
setting the transmitter's output power.
3, Item 10). The Priority button is used to select Priority mode operation. This mode can only be
3, Item 11). Used to switch the squelch facility on and off; it must be switched on before the
3, Item 12). The Select buttons have different functions for different operating modes.
CHs and CHt Buttons
(Figure
In Normal mode, the channel buttons are used to select, the required channel frequency.
In Scan mode, these buttons are used to resume scanning after a busy channel has been found and the
radio is paused, or on hold.
These buttons are also used as a fine adjustment when setting the transmitter's output power.
SCN Button
(Figure
the sequence to enter Test mode.
VOLs and VOLt Buttons
(Figure
do not adjust the loudspeaker volume.
Power Button
(Figure
this switch, it must be pressed, and kept pressed for approximately one second until the front panel
display shows On or Off.
3, Item 13). The Channel buttons have different functions for different operating modes.
3, Item 14). This button is used to switch on and off Scan mode. The scan button is also used in
3, Item 15). The Vol buttons are used to adjust the receiver's squelch threshold. These buttons
3, Item 16). The power button is used to switch on and off power to the radio circuits. When using
Note...
In addition to the front panel Power button, there is also a Power on/standby switch fitted on the
rear panel (see ‘Switching On and Off’ on page 20).
Warning!
Neither the Power button, nor the rear panel Power switch, isolates the input supply from the
equipment. Lethal voltages are still present in the base station's internal power supply. To
ensure safe working during maintenance, the ac and dc input supplies must be
disconnected from the base station.
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SWITCHING ON AND OFF
To switch on the base station:
(1) Ensure the Supply switch fitted to the base station's rear panel is set to on. Note that there is
no front panel indication as to whether the rear panel supply switch is on or set to standby.
(2) Press the front panel Power button for approximately one second until the display reads ‘On’.
Then release the button.
(3) Check that a warbling sound is heard for a few seconds and then a channel frequency is
displayed.
(4) The base station is now ready for use.
To switch off the base station, press the Power button until the display reads ‘Off’. Then release the
button. Note that this action removes power only from the radio module; power to other modules is
removed when the rear panel Supply switch is set to standby.
Warning!
Neither the Power button, nor the rear panel Power switch, isolates the input supply from the
equipment. Lethal voltages are still present in the base station's internal power supply. To
ensure safe working during maintenance, the ac and dc input supplies must be
disconnected from the base station.
Note ...
Always switch off the rear panel Power switch, and allow at least 10 seconds, before disconnecting
the ac and dc supply connectors. If this is not done, when next switched on the base station may
revert to previous channel and mode settings, and not those that were active immediately before
switching off.
Base Station Front Panel Power Button Location
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OPERATING THE BASE STATION IN NORMAL MODE
Operating the base station in Normal mode requires the following operations. Each operation is
explained in following paragraphs.
(1) Select Normal mode if not currently selected.
(2) Select the required channel frequency.
(3) Transmit using the fist microphone, and receive using the base station's internal
loudspeaker.
(4) Adjust, if necessary, the Squelch facility.
Selecting Normal Mode
Normal mode is active when neither Priority mode or Scan mode is selected. If Priority mode is selected,
the display shows ‘P’ every few seconds. If Scan mode is selected the display shows ‘Scn’ when
scanning, or the frequency when locked onto a busy channel. To select Normal mode if currently in
Priority or Scan mode:
To select Normal mode if currently in Priority mode, press the CH▲ or CH▼ button.
q
To select Normal mode if currently in Scan mode, press the SCN button.
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Selecting a Channel Frequency
To select the required channel frequency, press the CH▲or CH▼ button to scroll up or down through the
channel frequencies that are programmed into the base station. Release the button when the required
frequency is displayed.
In conjunction with the CH▲ and CH▼ buttons, the SEL▲ and SEL▼ buttons can be used to step
10 channels at a time.
Transmitting and Receiving
To key the transmitter press the fist microphone's PTT button. Check that the base station's Tx indicator
lights, and then speak clearly into the microphone.
Reception is heard through the base station's internal loudspeaker. The volume is adjusted using the
front panel's rotary Volume control that must be pushed in to switch on the loudspeaker. Users should
note that the VOL▲ and VOL▼ buttons do not adjust the volume. When a signal is received, the
base station's busy indicator lights if squelch is switched on; if squelch is switched off, the busy indicator
is permanently lit.
Switching and Adjusting the Squelch Facility
The base station has an adjustable squelch facility that can also be turned on and off. The squelch
facility, when correctly set, mutes unwanted background noise when no signals are being received.
During normal use of the base station the squelch facility should be switched on. After initially setting the
squelch level, there should be no reason to adjust it unless a problem is evident. The symptoms of an
incorrectly adjusted squelch level are:
q
Background noise is continuously, or intermittently heard when no signals are being received. If
this is the case, the setting is too low.
q
Weak signals (signals below the squelch threshold) are not being received. If this is the case, the
setting is too high.
These operating procedures assume the fist microphone that is normally supplied with the base station
is being used. As an alternative to the fist microphone, a microphone/headset can be used.
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