This documentation is applicable to receivers at Mod strike 7
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Specification
Operation
InstallationMaintenance
Approvals and
Standards
Approvals and Standards T6R VHF Receivers
Approvals:
The equipment is designed to meet the essential requirements of Directives
1999/5/EC, 89/336EEC as amended by Directive 93/68/EEC, and 72/23/EEC.
Standards:
The following standards are applied:
EMC EN 301 489-1; EN 301 489-22.
Health & Safety, EN 60950, CAN/CSA-C22.2 No. 60950, UL 60950.
Radio EN 300 676, IC RSS141, FCC part 15.
Telecom CS-03.
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FCC Statement:
This device has been tested and found to comply with the limits for a Class B digital device, pursuant
to part 15 of the FCC Rules. T hese limits are designed to provide reasonabl e protection against
harmful interference in a residential installation.
This equipment generates, uses and can radiate radio frequency energy and, if not installed and used
in accordance with the instructions, may cause harmful interference to radio communications.
However, there is no guarantee that interference will not occur in a particular installation.
If this equipment does cause harmful interference to radio or television reception, which can be
determined by turning the equipment off and on, the user is encouraged to try to correct the
interference by one or more of the fo llowing measures:
❑Reorient or relocate the receiving antenna.
❑Increase the separation between the equipment and the receiver.
❑Connect the equipmen t into an outlet on a circu it different from that to which t he receiver is
connected.
❑Consult the supplier or an experienced radio/TV technician for help.
Operation on 8.33 kHz channel spacing is restricted to European customers.
Specification
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This section gives the specification applicable to the T6T VHF Multimode Transmitter
operating in AM modes, Mode 2 and Mode 3.
All radios operate in AM-voice mode. Additional software must be loaded to allow AM-MSK,
Mode 2 and Mode 3.
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General Specification
The general specification applies to a transmitter irrespective of the selected operating mode. Sep arate
listings are given for AM modes, Mode 2 and Mode 3.
Variants
The T6T VHF Multimode Transmitter is available in the variants as listed in Table 1.
50 watt, high stability, standard
frequency coverage transmitter
50 watt, high stability, extended
frequency coverage transmitter
B6350/NB/501 18 to 136.975 MHzSupports 2, 3 and 4- offset
carrier operation
B6350/WB/501 12 to 155.975 MHzSupports 2, 3 and 4- offset
carrier operation
B6350HS/NB/501 18 to 136.975 MHzSupports 5-offset carrier
operation
B6350HS/WB/501 12 to 155.975 MHzSupports 5-of fset carrier
operation
Frequency accuracy
All variants except HSBetter than 1 ppm.
HS variants Better than 0.3 ppm.
Number of Channels
All variantsThe transmitter has a multichannel capability. 100 channels can be
stored and recalled.
Power Requirements
The transmitter operates from an ac mains supply, or a dc input supply. When both supplies are
connected, the dc input acts as an automatic backup for the ac mains.
ac input supplyThe transmitter operates from a 48 to 62 Hz single-phase ac supply
and automatically adjusts to operate from any supply voltage ranging
from 110 Vac to 240 Vac ±10%. The power consumption figures are
given in Table 2.
dc input supplyThe transmitter operates from a dc input supply between 21.6 and
32 V (measured at the radio’s input). Current loading is given in
Table 2.
T6T 50 W VHF TransmitterPage 2Specification
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Table 2 Power Consumption
RequirementNormal Operation
acdc
Maximum500 VA12 A
Not Transmitting60 VA1 A
Dimensions and Weight
The dimensions and weight of the transmitter are:
Width483 mm (19 inches).
Height88.9 mm (3.5 inches). The height occupies 2U of equipment cabinet
space.
Depth430 mm (16.9 inches) measured from front panel to rear panel.
450 mm (17.8 inches) measured from front panel to rear of fan.
Weight13.5 kg (29.76 pounds).
Environmental
Temperature rangeThe transmitter operates to specification across the temperature
range of -20°C to +55°C.
The transmitter can be stored at temperatures ranging from
-30°C to +70°C without causing any damage.
HumidityThe transmitter operates to specification at a relative humidity
between 5% and 90% non-condensing.
AltitudeThe radios operate to specification up to 15,000 feet. Additionally the
equipment is capable of storage at altitudes up to 50,000 feet without
damage.
Shock and vibrationThe radios comply with shock and vibration protection MIL-STD-810E,
method 516.4, procedure VI - Bench Handling.
VentilationThe transmitters are cooled by an integral fan, which normally runs at
half speed. At an RF PA temperature of 45°C this is increased to full
speed and at 40°C it reduces to half speed again.
The transmitters also include an additional temperature controlled fan
contained in the power supply.
Warm up timeAll variants are fully operational to specification within 20 seconds
after switch on except the T6T HS, which is fully operational within 20
seconds but can takes up to 10 minutes to achieve frequency
accuracy for offset carrier.
T6T 50 W VHF TransmitterPage 3Specification
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AM Modes
The transmitter can operate in AM-Voice mode (st andard) and A M -MSK mo de (opt ional). The following
specifications apply to both modes unless stated otherwis e.
Transmitter RF Characteristics
RF Power Outpu t
The RF carrier output power is a djustable in 1 W steps f rom 5 W to 50 W(as an option, the maxim um
selectable power can be limited).Output power is automatically controlled under the following conditions:
Frequency rangeVariations in power remain within -0 to +1 dB over the operational
frequency range.
Low supply voltageVariations in power remain within ±1 dB for supply voltages between
24 Vdc and 32 Vdc.
High VSWRLoop error can reduce power progressively by up to 3 dB. Variations
in power remain within ±1 dB into a VSWR of up to 2.5:1. At a VSWR
greater than this the output power may be reduced by 10 dB ±1 dB.
High RF PA temperatureIf the RF PA temperature sensor exceeds 80°C the output power is
reduced by 3 dB ±1 dB. If the RF PA temperature sensor exceeds
90°C the transmitter is de-keyed and automatically re-keyed at 70°C.
Duty Cycle
All variants100% continuous operation.
Channel Spacing
AM-Voice modeThe transmitters are capable of both 25 kHz channel spacing and
8.33 kHz channel spacing.
AM-MSK mode25 kHz.
Offset Carrier
Non-HS variants (AM-Voice)The non-HS T6T is capable of offsetting the carrier frequency to
provide 2, 3 and 4 carrier offset.
HS variants (AM-Voice)The HS T6T is capable of offsetting the carrier frequency to provide 2,
3, 4 and 5 carrier offset.
AM-MSK modeOffset carrier is not available.
Harmonic Outputs
All variantsSecond harmonic outputs are less than -36 dBm, third harmonic
outputs are less than -46 dBm and fourth harmonic outputs and above
up to 4 GHz, are less than -56 dBm.
T6T 50 W VHF TransmitterPage 4Specification
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Spurious Outputs
All variantsThe spurious outputs are less than -46 dBm for modulation depths up
to 90%, measured at greater than 500 kHz from carrier in the
frequency range 9 kHz to 4 GHz. There are no coherent spurious
outputs above the spectral mask at less than 500 kHz.
Intermodulation
All variantsIntermodulation products, caused by an interfering signal with the
same power as the transmitter isolated by 30 dB, are at least -40 dBc
at ≥±150 kHz and -50 dBc at ≥±500 kHz.
Transmitter Modulation Characteristics
The transmitter modulation characteristics are as follows:
(AM) full carrier; emission designator 6K80A3EJN for 25 kHz
channels and 5K00A3EJ N for 8.33 kHz channels.
AM-MSKAM-MSK mode uses Double Sideband (DSB) Amplitude Mod ulation
(AM) full carrier; emission designator 13K0A2DJN.
Modula tion Depth
All variantsThe transmitter is capable of modulation depths up to 95%.
Hum and Noise
All variantsThe hum and noise is more than 45 dB below the signal level for line
input levels <-13 dBm, and more than 50 dB below the signal level for
line input levels ≥-13 dBm, for a carrier modulated by a 1 kHz signal
with a modulation depth of 90%.
Frequency Response
25 kHz channel spacingAM-Voice and AM-MSK: The variation in frequency response with
reference to a 1 kHz signal is within +0.5 dB and -1.5 dB across the
frequency range 300 to 3400 Hz. The response is also less than -20
dB at 100 Hz and below, and less than -30 dB at 4 kHz and above.
8.33 kHz channel spacingAM-Voice only: The variation in frequency response with reference to
a 1 kHz signal is within +0.5 dB and -1.5 dB across the frequency
range 350 Hz to 2500 Hz. The response is also less than -10 dB at 100
Hz and below, and less than -30 dB at 3200 Hz and above.
Distortion
25 kHz channel spacingThe total harmonic distortion is less than 5% due to signals with a
modulation depth of 90%, within the frequency range 300 Hz to
3400 Hz.
8.33 kHz channel spacingAM-Voice only: The total harmonic distortion is less than 5% due to
signals with a modulation depth of 90%, within the frequency range
350 Hz to 2500 Hz.
T6T 50 W VHF TransmitterPage 5Specification
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Residual FM
All variantsFor a test signal of 1 kHz set at 80% modulation depth applied to the
line input of the transmitter, the unwanted peak frequency modulation
does not exceed ±500 Hz.
VOGAD
AM-VoiceThe VOGAD has an operational range of 30 dB. The VOGAD can be
disabled.
AM-MSKThe VOGAD is disabled.
Mute
AM-VoiceThe mute level is set at 15 dB below the average speech line level
setting. The mute can be disabled.
AM-MSKThe mute is disabled.
Differential Group Delay
AM-MSKThere is less than 60 µs differential group delay for signals in the
range 1200 to 2400 Hz.
Transmitter Control
Transmitter control characteristics are as follows:
Audio Inputs
All variantsVoice can be connected to the transmitter via the front panel
microphone connector. Voice can also be connect ed via the line
inputs. Line level setting from -30 to +10 dBm.
PTT Tim e Out
All variantsThe time out period is adjustable from 2 to 510 seconds in 2 second
steps or can be disabled.
T6T 50 W VHF TransmitterPage 6Specification
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Mode 2
This section gives the transmitter’s specification applicable to Mode 2 operation. Mode 2 parameters are
identical to AM-Voice mode parameters with the following exceptions:
RF Power Rise Time
All modelsT he transmitte r produces more than 90% of full power output within
the first 2 symbols of the power stabilization segment, which is the first
segment of the training sequence and consists of 4 symbols each
representin g 000.
RF Power Decay Time
All modelsThe output power decays by more than 20 dB within 2.5 symbols of
the middle of the final symbol.
Channel Spacing
All models2 5 kHz ch annel spacing only.
Transmitter Modulation Characteristics
Mode
All modelsMode 2 uses Carrier Sense Multiple Access (CSMA) differentially
encoded 8-phase shift keying (D8PSK), using a raised cosine filter
with α=0.6 (nominal value), emission designator 14K0G1DE.
Information is differentially encoded with 3 bits per symbol transmitted
as changes in phase rather than absolute phase. The data stream is
divided into groups of 3 consecutive data bits, least significant bit first.
Zeros are padded to the end of transmissions if needed for the final
channel symbol.
Modulation Rate
All modelsThe symbol rate is 10,500 symbols/second (±0.005%), resulting in a
nominal bit rate of 31,500 bits/s.
RMS Phase Error
All modelsT he RM S phase error is less than 3°. The error vector magnitude is
less than 6%.
Phase Acceleration
All modelsThe total frequency change during the transmission of the unique word
is less than 10 Hz. After this, the phase acceleration is less than
500 Hz/s.
T6T 50 W VHF TransmitterPage 7Specification
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Mode 3
This section gives the transmitter’s specification applicable to Mode 3 operation. Mode 3 parameters are
identical to AM-Voice mode parameters with the following exceptions:
RF Power Rise Time
All modelsT he transmitte r produces more than 90% of full power output within
the first 2 symbols of the power stabilization segment, which is the first
segment of the training sequence and consists of 4 symbols each
representin g 000.
RF Power Decay Time
All modelsThe output power decays by more than 20 dB within 2.5 symbols of
the middle of the final symbol.
Channel Spacing
All models2 5 kHz ch annel spacing only.
Transmitter Modulation Characteristics
Mode
All modelsMode 3 uses Time Division Multiple Access (TDMA) differentially
encoded 8-phase shift keying (D8PSK), using a raised cosine filter
with α=0.6 (nominal value), emission designator 14K0G7WET.
Information is differentially encoded with 3 bits per symbol transmitted
as changes in phase rather than absolute phase. The data stream is
divided into groups of 3 consecutive data bits, least significant bit first.
Zeros are padded to the end of transmissions if needed for the final
channel symbol.
Modulation Rate
All modelsThe symbol rate is 10,500 symbols/second (±0.005%), resulting in a
nominal bit rate of 31,500 bits/s.
RMS Phase Error
All modelsT he RM S phase error is less than 3°. The error vector magnitude is
less than 6%.
Phase Acceleration
All modelsThe total frequency change during the transmission of the unique word
is less than 10 Hz. After this, the phase acceleration is less than
500 Hz/s.
End of document
T6T 50 W VHF TransmitterPage 8Specification
Operation
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This document describes the controls, indicators, setting up and operating instructions
applicable to the T6T VHF Multimode Transmitter.
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Controls , Indicators and Front Panel Connectors
This part details the purpose of all controls and indicators of the T6T transmitters.
Front Panel
The front panel’ s controls, indicators an d connectors are shown below and detailed in the following
paragraphs.
Scroll/Select SwitchLCD
ALARM
TRANSMIT
READY
STANDBY
F r e q 1 1 8 .0 0 0 M H z
C h 1 0 0 + 7 . 3 k H z
M o d e A M V o i c e 1
P w r
SCROLL/
SELECT
REFERENCE
MICROPHONE/
DIAGNOSTICS
Scroll/Select Switch and LCD
The Scroll/Select switch is used in conjunction with the LCD to select most of the transmitter's operational
settings. Use of the switch and LCD is fully detail ed in this section appl icable to th e particular operating
mode. During normal operation, the LCD shows the operating frequency, the channel number (if the
channel store f acility is used), the carrier offset (if used), and dis plays a graphical representatio n of
instantaneous peak power.
The example LCD sc reen above shows the t ransmitter operating on 11 8.000 MHz; the frequen cy has
been preset as channel 100 and offset at +7.3 kHz.
Ready Indicator
A green indicator that lights when the transmitter is ready for use and no BIT faults have been detected.
Transmit Indicator
An amber indicator that lights when the transmit circuit is keyed and producing output power.
Alarm Indicator
A red indicator that either flashes, or lights, when a BIT fault has been det ected. BIT indications are
classified as either Alarms or Alerts.
If an ‘alert’ condition is detected, the Alarm ind icator flashes, the Ready indicator remains lit, and the
transmitter remains operational. A BIT ‘alert’ is indicated if:
❑If the transmitter RF output powe r has redu ced from its setting by m ore than 1 dB but not more
than 3 dB.
❑If the supply volts falls below a pre-defined level.
Any other BIT condition results in an alarm. When detected, the Alarm indicator lights and the Ready
indicator becomes unlit; the transmitter cannot be used.
T6T VHF 50 W TransmitterPage 2Operation
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Standby Indicator
A red indicator that lights when the tra nsmitter is in stan dby m ode. When in standby mode, m ost of the
radio's circuits are inactive, the front panel LCD is blanked, and the transmitter cannot be keyed.
Standby mode is selected and deselected using the front panel Scroll/Select switch and LCD, by initiating
an instruction through a MARC system, through a T6 controller or through the VFP. For details of front
panel selection and deselection see page 13.
Reference Connector
An SMB jack socket that allows a frequency counter to monitor the transmitter's reference frequency.
This connector is used only for maintena nce purposes. The instruction s for checking and adjusting the
reference frequency are given in the Maintenance section.
Microp ho ne / D i agnostics Connector
A dual purpose c onnect or t hat all ows ei ther a m icrophone, or a PC, t o be connected to th e t ransmi tter.
The connector is a 7-pin self-locking DIN socket; the pin-out is shown inTable 1.
A microphone i s fitted to t his connector to enable the t rans mitter to be operated in AM local mo de. The
connections are detailed inTable 1. A PC can also be connected to allow the VFP to be displayed. Using
the VFP is detailed in the Mai ntenance section. The PC connections at the transmitter are s hown in
1Microphone ground-0 V.
3Microphone PTTInput0 V to PTT.
5SidetoneOutput0 to 3 V pk-pk.
6Micro phone inputInput2 to 35 mV rms on Passive setting and 8 to 140 mV rms on
7Ground-0 V.
SignalInput or
Output
Description
Active setting to remain in VOGAD range.
T6T VHF 50 W TransmitterPage 3Operation
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Table 2 Microphone/Diagnostics Connector - PC Connections
Pin
Number
2Transmit dataOu tputRS232, 115200 baud, 8 data bits, 1 stop bit, no parity, no
4Receiv e dataInputRS232, 1 15200 baud, 8 data bits, 1 stop bit, no parit y, no
7Ground-0 V.
SignalInput or
Output
Description
handshaking.
handshaking.
Rear Panel Power Switch
The rear panel's power switch is a 2-way rocker switch used to select between power on, and standby.
WARNING
When the POWER SWITCH is set to the Standby position, dangerous voltages are still
present in the transmitter's internal power supply circuitry. To ensure safe working, the
transmitter must be isolated from the ac and dc input supplies.
Dangerous Voltages
= Standby= On
T6T VHF 50 W TransmitterPage 4Operation
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Setting Up and Operation
Introduction
Setting up the transmitter involves sele cting various parameters using the Virtual Front Panel (VFP),
through a Multi-Access Remote Control (MARC) system, from a T6 controller, or from the transmitter’s
front panel. The transmitter can be configured for remote or local use.
Table 9 on page 30 details the functions and parameters that can be set from all these sources.
The rest of this document details how to configure the transmitter from the front panel, and how to operate
the radio in local mode.
Selecting most of the transmitter's operational settings is carried out using the front panel Scroll/Select
switch and the LCD (see the illustration below). No attempt to set up the transmitter should be made until
the transmitter has been installed as per the installation procedures given in the Installation section.
Normal Operation
During normal operation, the LCD displays the Main screen. This screen shows the operating frequency,
the channel number ( if the channel store fac ility is used), the carrier offset (if used), and displays a
graphical representation of output power when the transmitter is keyed. If the transmitter has been set to
Standby mode, which is shown by the front panel Standby indicator being lit, the LCD is blanked.
Scroll/Select SwitchLCD
ALARM
TRANSMIT
READY
STANDBY
F r e q 1 1 8 .0 0 0 M H z
C h 1 0 0 + 7 . 3 k H z
M o d e A M V o i c e 1
P w r
SCROLL/
SELECT
REFERENCE
MICROPHONE/
DIAGNOSTICS
Using the Scroll/Select Switch
The Scroll/Select switch (ref erred to throughout this section as the ‘Switch’) is used to l eave the Main
screen and display the Control screen (see page 8). Further use of the Switch displays various selection
menus and allows the required pa rameters to be set. The switch has three actions: it can be turned
clockwise, anti-clockwise, or momentarily pushed in.
T6T VHF 50 W TransmitterPage 5Operation
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Screen Protocol
The following protocol is applicable to all screens described in this document.
Main ScreenDuring normal operation, the Main screen (an example of which is shown below
whilst the transmitter is transmitting) is displayed.
F re q1 1 8 .0 0 0 M H z
C h 1 0 0+ 7 .3 k H z
M o d eA MV o ic e
P w rIIIIIIIIII
SwitchRefers to the front panel Scroll/Select switch. The switch is turned clockwise to scroll
through fields from left to right, and from top to bottom. The switch is turned
anti-clockwise to scroll through fields from right to left, and from bottom to top. The
switch is pressed to make a selection.
Time outIf during any setting up procedure the Scroll/Select switch is not operated for
30 seconds, the display returns to the Main screen. If editing any parameter has not
been completed, the transmitter stays on the original setting.
>>Indicates more fields are available other than those currently displayed. To access
those fields, turn the switch clockwise through the last displayed field.
<<Indicates more fields are available other than those currently displayed. To access
those fields, turn the switch anti-clockwise through the first displayed field.
BackWhen Back is selected, you are returned to the previous menu.
ExitWhen Exit is selected, you are returned to the Main screen.
Menu System
The front panel control of the radio is implemented through a hierarchical menu system as shown on the
following page.
T6T VHF 50 W TransmitterPage 6Operation
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Main Page
F re q1 1 8 .0 0 0 M H z
C h 1 0 0
M o d eA MV o ic e
P w rIIIIIIIIII
Main Screen
(Example)
Displayed during normal
transmitt er operation
Frequency
Set the
transmitter
operating
frequency
Backlight
Adjust the
display’s
backlight
Control Screen
Configure the transmitter
operating par ameters , access
the BIT facility or view the
software configuration
Channel
Set or reca ll up
to 100 preset
frequency
channels
.
Settings
Set the
transmitter
operational
settings
Ref Freq
Adjust the
transmitter
reference
frequency
Initiate a BIT
test and view
Band Edges
Set up the
transmitter
band edges
Menu Lock Screen
(see page 8)
BIT
results
S/W Config
transmitter
configuration
Mode and
Mode
Settings
Select Mode
View the
software
Standby
Enter or Exit
standby mode
Polarities
Set the active
polarity for
certain hardwire
connections
AM-Voice Mode
Settings
(see page 16)
AM-MSK Mode
Settings
(see page 18)
Digital Modes
(see page 19)
Menu System
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Menu Lock S creen
A security facility available only from the VFP allows the transmitter's front panel to be ‘locked’. When
this facility is active, no operational settings can be made from the front panel until an ‘unlock’ command
is sent from the VFP.
The following screen is displayed when ‘lock’ is active, and the front panel switch is pressed.
S E C U R IT YM E S S A G E
F ro n tP a n e l
L o c k e d
O K
To exit the system lock screen:
❑Select OK, then press the switch. You are returned to the Main screen.
or,
❑Wait for the 30 second time-out to expire. You are returned to the Main screen.
Control Screen
The Control screen is entered from the Main screen by pressing the switch. T he following screen is
displayed:
Change the transmitter’s operating frequency.
Store or recall preset channel frequencies.
Select operating mode and m ode settings.
Initiate a BIT test and view results.
View software configuration.
Enter or exit standby mode.
F re q u e n c y
C h a n n e l
S e ttin g s
E x it> >
B I T
S / WC o n fi g
S t a n d b y
E x it< <
T6T VHF 50 W TransmitterPage 8Operation
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Notes for Setting Up the Transmitter
The following notes should be read before setting up the transmitter. They advise on the special
frequency display when using 8.33 kHz channel spacing, a nd g ive guidance on the optimum li ne level
settings. Note that for operation in the United States of America, this equipment is certified only for
operation using 25 kHz channel spacing.
Front Panel Display for 25 kHz and 8.33 kHz Channel Spacing
When setting the opera ting frequency of the transmitter and 8 .33 kHz channel spac ing is required, the
displayed frequency differs from the actual channel frequency. Table 3 shows the pattern used for
25 kHz and 8.33 kHz spaced channel frequencies from 118.000 MHz to 118.141 MHz. The pattern is the
same for any frequency within the transmitter's frequency range. The display conforms to ICAO
convention for 8.33 kHz operation.
Table 3 25 kHz and 8.33 kHz Channel Spacing Displays
The input line level setting displayed on the front panel is equivalent to the a vera ge speec h le vel with a
peak-to-average ratio of 13 dB. This corresponds to the level specified for the lines.
When testing the transmitter using a sine wave, the line input level should be set to 10 dB above the line
level setting. The VOG AD and mute t hresholds are pre-set at 10 dB and 15 dB respectively below the
line level setting.
Table 4 shows the relationship between the input line level, VOGAD threshold and mute threshold.
T6T VHF 50 W TransmitterPage 9Operation
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Table 4 Relationship Between Line Level, VOGAD Threshold and Mute Threshold
Line Level Setting
(dBm)
+10+10+200-5
+5+5+15-5-10
00+10-10-15
-5-5+5-15-20
-10-100-20-25
-15-15-5-25-30
-20-20-10-30-35
-25-25-15-35-40
-30-30-20-40-45
Average Speech
Level (dBm)
Sine Wave Level
(dBm)
VOGAD Threshold
(dBm)
Mute Threshold
(dBm)
Changing the Transmitter’s Operating Frequency
The transmitter’s frequency can be changed in two ways: either from the frequency screen, or by
recalling a preset channel. This procedure details using the Frequency screen.
(1)From the Control screen, select
frequency to display the Frequency
screen.
F r e q1 1 8 .0 0 0 M H z
(2)Turn the switch to highlight the digit to
be changed, then press the switch.
(3)Turn the switch until the required digit
is shown, then press th e swit ch.
(4)Repeat until the required freq uency is
shown, then highlight OK and press the
switch.
(5)Only frequencies that fa ll between the
band edge settings can be selected.
C a n c e lO K
T6T VHF 50 W TransmitterPage 10Operation
To Store and Recall Frequency Channels
Up to 100 frequency channels can be stored in the transmitter.
To store a Channel Frequency
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(1)From the Control screen, select
Channel to display the Channel
screen. Highlight Channel, press the
switch and then turn it until the required
channel number is displayed; press the
switch.
(2)Highlight the MHz frequency value
(see Example 2) press the switch and
then turn it until the required MHz value
is shown. Press the switch.
(3)Highlight the kHz frequency value (see
Example 3), press the swi tch and then
turn it until the required kHz value is
shown. Press the switch.
(4)Highlight Store and press the switch.
The new frequency is now stored in the
selected channel number.
To recall a Stored Frequency Channel
(1)From the Control screen, select
Channel to display the Channel
screen.
(2)To make the transmitter operate on
any preset channel frequency,
highlight Channel and press the switch.
Turn the switch until the required
channel number/frequency is
displayed, then press the switch.
(3)Turn the switch to highlight Recall, then
press the switch. Exit the screen. The
transmitter now operates on the
recalled channel frequency.
C h1 0 0
F r e q1 2 1 . 5 0 0 M H z
R e c a ll
B a c kE x it
Channel Screen - Example 1
C h1 0 0
F r e q1 1 8 . 0 0 0 M H z
S t o r e
B a c kE x it
Channel Screen - Example 2
C h1 0 0
F r e q1 1 8 . 0 0 0 M H z
O u t s i d eB a n d E d g e
B a c kE x it
Channel Screen - Example 3
C h1 0 0
F r e q1 1 8 . 0 0 0 M H z
I nn v a li df o rM o d e
B a c kE x it
Channel Screen - Example 4
Notes:
If a frequency outside the band edge limits is
entered, a message (see Channel Screen Example 3) is displayed.
If a frequency not valid for the mode of
operation is entered, a message (see Ch annel
Screen - Example 4) is displayed.
T6T VHF 50 W TransmitterPage 11Operation
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To Initiate a BIT Test
Use the following procedure to initiate an interruptive BIT test from the transmitter's front panel. A BIT
test cannot be initiated while the transmitter is keyed. After a BIT test has been run, the BIT screen is
displayed (see AM-Voice and AM -MSK BIT Screen on page 24). An i nterruptive BIT tes t cannot be
initiated in Mode 2 or Mode 3.
During an interruptive BIT te st, the t ransm itter radiates m odulated carrier waves at the s et power.
Users should therefore obtain the necessary authority before initiating a test.
If the test is to be carried out with the antenna disconnected, ensure a load is fitted to the
transmitter's antenna connector.
In order to test the line input stages, an internally generated 1 kHz tone is injected into the line input
circuit. Any other audio present on the line input will cause the test to be inaccurate. Therefore the
transmitter must not be keyed during the test.
(1)From the Main screen, press the switch to display the Control screen. Turn the switch until BIT
is highlighted. Press the switch.
B I T
S / WC o n fig
S t a n d b y
E x it< <
(2)Ensure the BIT me nu is displayed. Turn the switch u ntil BIT Initiate is highlighted. Press the
switch.
B I TI n itia t e
E T I0 0 0 0 0 : 0 0 h r s
A CS u p p lyO N
E x it> >
(3)During the test, which takes approximately two seconds, the Testing screen is displayed.
T e s tin g
P le a s eW a it
T6T VHF 50 W TransmitterPage 12Operation
Back to Transmitter
Main Page
(4)On completion, and if the interruptive test was initiated from the front panel, one of the following
screens will be shown.
T e s tS t a tu s
P A S S
O K
(5)Selecting OK takes the user back to the BIT screen.
T e s tS t a tu s
F A I L
O K
(6)Selecting OK takes the user back to the BIT screen. The user can then scroll through the screen
to check out transmitter parameters for failure.
Standby Mode
Standby mode is a pow er saving feature that can be used for non-operat ional transmitters. When in
standby mode, most of the transmitter's circuits are inactive, the LCD is blanked, and the transmitter
cannot be keyed. To put the transmitter into standby mode, use the following procedure.
When the transmitter is in Standby mode, the red front panel Standby indicator is lit.
To Enter Standby Mode
(1)From the Control screen select
Standby.
(2)At the Standby screen, select Yes.
(3)Check that the display blanks and
the front panel Standby indicator is
lit.
To Exit Standby Mode
(1)Press the Switch.
(2)Select Yes.
(3)Check that the Main screen is
displayed and that the front panel
Standby indicator is unlit.
E n t e rS t a n d b y ?
Y e sN o
E x itS t a n d b y ?
Y e sN o
T6T VHF 50 W TransmitterPage 13Operation
Back to Transmitter
Main Page
Settings
Operational settings for the T6T VHF transmitter are configured at the front panel, through the VFP, and
through an associated MARC system (or compatible control system). Some settings can also be made
remotely via a T6 controller. The Settings screen is entered from the Control screen.
The settings that can be selected at the front panel Settings screen are:
❑Mode - either AM-Voice, AM-MSK, Mode 2 or Mode 3
❑Mode Settings - allows the selected mode parameters to be set
❑Polarities
❑Band edges
❑Backlight
❑Reference frequency.
Note that the mode selection, ref erence frequency and backlight are set from this screen. W hen mode
settings, polarities and band edges are selected the user is taken to other screens.
M o d eA MV o i c e
M o d eS e tti n g s
P o l a riti e s
E x it> >
B a n dE d g e s
R e fF re q5 0 .0 %
B a c k lig h t0 3 0 s
E x it< <> >
B a c k
E x it
Notes:
Select between AM-Voice, AM-MSK, Mod e 2 or Mode 3.
Select to take you to the mode specific Settings menu.
Select to take you to the Polarities menu.
Set the transmitter’s frequency band edges.
Align the transmitter’s reference frequency (Note 1).
Adjust the LCD’s backlight time out (Note 2).
1.Setting the transmitter’s reference frequency is a maintenance operation. The current value should
not be reset unless the correct test equipment is connected. See the Maintenance section.
2.The LCD’s backlight can be s et for permanent ly on, off, or timed t o stay on for a pe riod between
15 and 120 seconds.
General and mode specific settings, showing default values, are referenced in Table 5 on page 15. Click
on any required parameter by page number for further references.
T6T VHF 50 W TransmitterPage 14Operation
Table 5 Opera tio nal Settings fr om t he Front Panel
Menu lock screenAllLocked or unlockedUnlockedpage 8
Enter standby
mode
Exit standby modeAllYes or No-page 13
Set mode of
operation
Set polaritiesAM-voice,
Band edgesAll118.000 to 136.975 MHz
LCD BacklightAll15 to 120 s, On or Off30 spage 14
RF powerAll5 to 50 W50 Wpage 16
Audio line in levelAM-voice,
InhibitAM-voice,
PTT (key)AM -voice,
Tx time outAM-voice,
Modulation depthAM-voice,
MuteAM-voiceO n or OffOnpage 16
VOGADAM-voiceO n or OffOnpage 16
Antenna C/O delayAM-voice
AllYes or No-
AllAM-voice, AM-MSK, Mode
2 or Mode 3
STD or INVSTDpage 20
AM-MSK
or
1 12.000 to 155.975 MHz
-30 to +10 dBm-13 dBmpage 16 and
AM-MSK
On or OffOffpage 16 and
AM-MSK
On (key), Off (de-key)Offpage 16 and
AM-MSK
2 to 510 s or Off180 spage 16 and
AM-MSK
5 to 95%85%page 16 and
AM-MSK
On or OffOn
AM-voicepage 14
118.000 and 136.975 MHz
or
112.000 and 155.975 MHz
Reference
page 13
page 28
page 18
page 18
page 18
page 18
page 18
page 16
AM-MSK
OffsetAM-voice0, ±2.5, ±5, ±7.3, ±7.5 kHz
(additionall y, ±4 and
±8 kHz on HS models)
Ste pAM-voice8.33 kHz, 25 kHz or both25 kHzpage 17
MicAM-voiceActive or PassivePassivepage 17
Key priorityAM-voice,
AM-MSK
Local PTTA M-voice,
AM-MSK
Remote PTTAM-voice,
AM-MSK
Remote phantom
PTT
T6T VHF 50 W TransmitterPage 15Operation
AM-voice,
AM-MSK
Local-Remote or
Remote-Local
Enabled or DisabledEnabledpage 17 and
Enabled or DisabledEnabledpage 17 and
Enabled or DisabledEnabledpage 17 and
Off
0 (No offset)page 17
Local-Remotepage 17 and
page 18
page 18
page 18
page 18
page 18
Back to Transmitter
Main Page
AM Voice Settings Procedure
During this procedure, the following parameters, applicable to AM-voice operation, can be set:
❑RF power output
❑Audio line input level
❑Inhibit
❑PTT on (key) or off (de-key)
❑Transmitter time out
❑Modulation depth
❑Mute (on or off)
❑VOGAD (on or off)
❑Antenna c/o delay (on or off)
❑Offset
❑Step
❑Mic
❑Key priority ( local or remote)
❑Enable or disable local PTT
❑Enable or disable remote PTT
❑Enable or disable remote phantom PTT.
AM Voice Mode Settings Screen
The AM-voice mode setting screen is accessed from the Settings screen. Use the Scroll/Select switch to
select the parameter, then enter the required setting(s).
Adjustments
P o w e r5 0 W
L i n eI n- 1 3 d B m
I n h ib itO F F
E x it> >
P T TO F F
T XT im e o u t1 8 0 s
M o dD e p th8 5 %
E x it< <> >
RF power between 5 W to 50 W.
Audio line in level between -30 to +10 dBm.
On or Off.
On (key), Off (de-key).
2 to 510 s.
5 to 95%.
M u teO N
V O G A DO N
A n tC /OD e lO N
On or Off.
On or Off.
On or Off.
E x it< <> >
T6T VHF 50 W TransmitterPage 16Operation
Adjustments
Back to Transmitter
Main Page
O ffs e t0 .0 k H z
S te p2 5 k H z
M icP A S S IV E
E x it< <> >
K e yP r io r ityL - R
L o c a lP T TE N
R e m o teP T TE N
E x it< <> >
R e mP h a nP T TE N
B a c k
E x it< <
0, ±2.5, ±5, ±7.3, ±7.5 , (or ±4, ±8 HS only) kHz.
25 kHz, 8.33 kHz or both.
Active or Passiv e.
Local-remote or Remote-local.
Enabled or Disabled.
Enabled or Disabled.
Enabled or Disabled.
Return to screen.
T6T VHF 50 W TransmitterPage 17Operation
Back to Transmitter
Main Page
AM-MSK Mode Se ttings Proced ure
During this procedure, the following parameters, applicable to AM MSK operation, can be set:
❑RF power output
❑Audio line input level
❑Inhibit
❑PTT on (key) or off (de-key)
❑Transmitter time out
❑Modulation depth
❑Antenna c/o delay (on or off)
❑Key priority ( local or remote)
❑Enable or disable remote PTT
❑Enable or disable remote phantom PTT.
AM-MSK Mode Sett ings Screens
The AM-MSK mode setting screen is accessed from the Settings screen. Use the Scroll/Select switch to
select the parameter, then enter the required setting(s).
P o w e r5 0 W
L i n eI n- 1 3 d B m
I n h i b itO F F
E x it> >
P T TO F F
T XT im e o u t1 8 0 s
M o dD e p th8 5 %
E x it< <> >
A n tC /OD e lO N
K e yP r io rityL - R
L o c a lP T TE N
E x it< <> >
Adjustments
RF power between 5 W to 50 W.
Audio line in level between -30 to +10 dBm.
On or Off.
On (key), Off (de-key).
2 to 510 s.
5 to 95%.
On or Off.
Local-remote or Remote-local.
Enabled or Disabled.
R e m o teP T TE N
R e mP h a nP T TE N
Enabled or Disabled.
Enabled or Disabled.
B a c k
E x it< <
T6T VHF 50 W TransmitterPage 18Operation
Mode 2 Settings Screen
This is an advisory screen. Pressing OK returns the user to the Main screen.
M o d e 2p a ra m e te r s
a res e tv iath e
H L D Cin te r fa c e
O K
Mode 3 Settings Screen
This is an advisory screen. Pressing OK returns the user to the Main screen.
M o d e 3p a ra m e te r s
a res e tv iath e
T 1 /E 1in te r fa c e
O K
Back to Transmitter
Main Page
T6T VHF 50 W TransmitterPage 19Operation
Back to Transmitter
Main Page
Polarities Screens AM-Voice and AM-MSK
A number of remote indication and control signals can be hard-wire connected to the transmitter. These
signals include a transmitter ready indication, a PTT control signal, a phantom PTT control signal, a PTT
out indication, a transmitter inhibit control signal, a BIT test initiation control signal, an external VSWR
fault indication and antenna C/O. The following paragraphs detail the signals applicable to the
operational mode of the transmitter.
The Polarities screen is accessed from the Settings screen.
AM-Voice and AM-MSK Polarity Settings
R e a d yO u tS T D
E - B I TI nS T D
I n h i b itI nS T D
E x it> >
B ITS ta r tInS T D
P T TR e f+ 1 4 V
P T TInS T D
E x it> >
P h a nP T TInS T D
P T TO u tS T D
F a s tP T TO u tS T D
E x it< <> >
E x tV S W RInS T D
A n tC /OO u tS T D
B a c k
E x it< <
Each of ten polarity settings applicable to
AM-voice and AM-M SK can be set to the default
STD (standard) setting or INV (inverted).
The signal conn ections are shown in T able 6 on
page 21 along with the conditions when STD or
INV is selected.
The settings for the PTT Reference voltage are
also shown in Table 6.
T6T VHF 50 W TransmitterPage 20Operation
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