jotron TR-7750C, TA-7650C, RA-7203C Operator's Manual

Jotron AS| TR7750C: Operators Manual  Introduction

Page ii

Approvals
The equipment is designed to meet the essential requirements of European Directives 1999/5/EC,
89/336EEC as amended by Directive 93/68/EEC and 72/23/EEC

Standards

The following standards are applied:

EMC: EN301843-1 and EN301843-2

FCC part 80
Health and Safety: EN60950
Radio specifications: EN301929-1 and EN301929-2

For an updated list of approvals and statements of conformity, these are available on:

www.jotron.com

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Introduction

Page iii

List of abbreviations and definitions

BITE

Built In Test Equipment

bps

Bits Per Second.

DSP

Digital Signal Processor

ETSI

European Telecommunication Standardisation Institute

ICAO

International Civil Aviation Organization

IEC

International Electro-technical Commission.

LAN

Local Area Network

PA

Power Amplifier

PSU

Power Supply Unit. Separate unit to power the equipment.

PTT

Push To Talk

RF

Radio Frequency

S/N

SIGNAL- TO-NOISE RATIO

SNMP

Simple Network Management Protocol, a network protocol used to control the radio equipment.
This equipment is defined as an AGENT in a SNMP system.

VSWR

Voltage Standing Wave Ratio

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Introduction

Page iv

NO

INIT

DATE

CHAPTERS

VERSION

REASONFOR CHANGE
1

ES

13.08.08

All

84748_O

New product

2

OH

11.11.08

3.2.5, 3.2.6, 3.2.7,

3.4.4, 3.4.5, 3.4.6

B

Information regarding Frequency stability,
Hardware Key and protection of I/O lines added.

3

ES

29.06.09

3-5 C Information regarding type of LAN cable

4

OH

10.11.09

3.4.5, 1.1

D

Pin 8 Aux 2 is N/C, Output power configuration
range in radio model table.

5

BA

05.04.13

3.2.7, 3.2.8, 3.4.6,

4.6.1

E

Fixed RS485 polarity error.

6

BR

28.04.14

4.4 F FCC and IC approval

7

BA

04.06.14

Page vi

G

Added warning statement, modification warning
statement and digital device statement.

8 9
10

11

12

13

14

15

16 17 18 19

20

Amendment Record

The information in this book has been carefully checked and is believed to be accurate. However, no
responsibility is assumed for inaccuracies.
Jotron AS reserves the right to make changes without further notice to any products or modules
described herein to improve reliability, function or design. Jotron AS does not assume any liability
arising out of the application or use of the described product.

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Introduction

Page v

SAFETY INSTRUCTIONS

CAUTION!
This equipment contains CMOS integrated circuits. Observe handling precautions to avoid static
discharges which may damage these devices.

WARNING!
Some RF semiconductor devices used in this equipment may contain Beryllium Oxide. If inhaled, dust
from this oxide can be toxic. No danger will arise from normal handling but no attempt should be
made to tamper with these devices. On no account must these transistors be destroyed or discarded
with industrial or domestic waste, but should be returned to the manufacturers for subsequent
disposal.

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Introduction

Page vi

WARNING STATEMENT

This device complies with part 15 of the FCC Rules. Operation is subject to the following two
conditions: (1) This device may not cause harmful interference, and (2) this device must accept any
interference received, including interference that may cause undesired operation.

MODIFICATION WARNING STATEMENT

Changes or modifications not expressly approved by the party responsible for compliance could void
the user's authority to operate the equipment.

DIGITAL DEVICE STATEMENT

This equipment has been tested and found to comply with the limits for a Class B digital device,
pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable 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 following measures:

--Reorient or relocate the receiving antenna.

--Increase the separation between the equipment and transceiver.

--Connect the equipment into an outlet on a circuit different from that
to which the transceiver is connected.

--Consult the dealer or an experienced radio/TV technician for help.

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Introduction

Page viii

TABLE OF CONTENTS

1 INTRODUCTION ....................................................................................................................... 1-1

1.1 MODELS COVERED BY THIS MANUAL ..................................................................................... 1-1

1.2 LAYOUT OF THE TRANSCEIVER .............................................................................................. 1-1

1.3 APPLICATIONS ........................................................................................................................ 1-2

2 TECHNICAL SPECIFICATIONS ............................................................................................ 2-1

2.1 GENERAL SPECIFICATION, TRANSCEIVER UNITS, TR-7750C ................................................ 2-1

2.2 TRANSMITTER UNITS, TA-7650C .......................................................................................... 2-1

2.3 RECEIVER UNIT, RA-7203C ................................................................................................... 2-2

2.4 POWER SUPPLY UNIT, PSU-7002 ........................................................................................... 2-2

3 FUNCTIONAL DESCRIPTION ............................................................................................... 3-1

3.1 FRONT PANEL CONTROLS, TRANSMITTER UNIT .................................................................... 3-1

3.1.1 Display ............................................................................................................................ 3-1

3.1.2 Scroll/Select switch and Navigation buttons A, B and C ................................................ 3-1

3.1.3 PTT button ...................................................................................................................... 3-1

3.1.4 ON/OFF button ............................................................................................................... 3-1

3.1.5 LED Indicators ............................................................................................................... 3-2

3.1.6 Mic/Headset connector ................................................................................................... 3-2

3.2 TRANSMITTER, REAR CONNECTIONS ...................................................................................... 3-4

3.2.1 Antenna connector (50 ohm N) ....................................................................................... 3-4

3.2.2 Receiver ant. Connector (50 ohm BNC) ......................................................................... 3-4

3.2.3 DC input connector (Amphenol MS 3106A 10SL4S)(Jotron P/N: 96715) ..................... 3-4

3.2.4 LAN connector (RJ45) .................................................................................................... 3-5

3.2.5 AUX1 CONNECTOR (RJ45) .......................................................................................... 3-5

3.2.6 AUX2 connector (RJ45) .................................................................................................. 3-6

3.2.7 REM connector (RJ45) ................................................................................................... 3-6

3.2.8 Rx connector (RJ45) ....................................................................................................... 3-7

3.3 FRONT PANEL CONTROLS, RECEIVER UNIT ........................................................................... 3-8

3.3.1 Display ............................................................................................................................ 3-8

3.3.2 Scroll/Select switch and Navigation buttons A, B and C ................................................ 3-8

3.3.3 ON/OFF button ............................................................................................................... 3-8

3.3.4 LED Indicators ............................................................................................................... 3-8

3.3.5 Headset connector .......................................................................................................... 3-9

3.4 RECEIVER, REAR CONNECTIONS ........................................................................................... 3-10

3.4.1 Antenna connector (50 ohm N) ..................................................................................... 3-10

3.4.2 DC input connector (Amphenol MS 3106A 10SL4S)(Jotron P/N: 96715) ................... 3-10

3.4.3 LAN connector (RJ45) .................................................................................................. 3-11

3.4.4 AUX1 CONNECTOR (RJ45) ........................................................................................ 3-11

3.4.5 AUX2 connector (RJ45) ................................................................................................ 3-12

3.4.6 REM connector (RJ45) ................................................................................................. 3-12

3.5 PSU-7002, POWER SUPPLY UNIT, FRONTVIEW .................................................................... 3-13

3.5.1 LED Indicators ............................................................................................................. 3-13

3.6 POWER SUPPLY UNIT REAR CONNECTORS. .......................................................................... 3-14

3.6.1 DC input connector (Amphenol MS 3106A 10SL4S)(Jotron P/N: 96715) ................... 3-14

3.6.2 DC Output Connector(Amphenol MS 3106A 12S3P)(Jotron P/N: 93697) .................. 3-14

3.6.3 AC Input connector ....................................................................................................... 3-15

4 INSTALLATION ........................................................................................................................ 4-1

4.1 INTRODUCTION. ...................................................................................................................... 4-1

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4.2 INITIAL INSPECTION ............................................................................................................... 4-1

4.3 INSTALLATION INTO EQUIPMENT CABINET ............................................................................ 4-2

4.4 ANTENNA CONNECTORS ......................................................................................................... 4-2

4.5 AC AND DC CONNECTORS ..................................................................................................... 4-2

4.6 REMOTE SIGNALS ................................................................................................................... 4-2

4.6.1 REM connector (receiver) and RX connector (transmitter) ........................................... 4-3

4.6.2 Audio in/out and Line loop keying .................................................................................. 4-6

4.6.3 Other key signals ............................................................................................................ 4-9

4.6.4 Squelch and AGC signals, receiver unit ....................................................................... 4-11

4.6.5 Alarm and Select signals transmitter and receiver ....................................................... 4-12

4.6.6 Miscellaneous signals, transmitter ............................................................................... 4-14

4.7 APPLICATIONS ...................................................................................................................... 4-15

4.7.1 Transceiver, local configuration................................................................................... 4-15

4.7.2 Transceiver, remote configuration ............................................................................... 4-18

4.7.3 Transmitter, main / backup configuration .................................................................... 4-20

4.7.4 Receiver, main / backup configuration ......................................................................... 4-22

5 OPERATING INSTRUCTIONS ............................................................................................... 5-1

5.1 INTRODUCTION ....................................................................................................................... 5-1

5.2 USER MENU – TRANSMITTER (RESTRICTED ACCESS LEVEL) .................................................. 5-2

5.3 USER MENU – TRANSMITTER (DEFAULT ACCESS LEVEL) ....................................................... 5-3

5.4 SETTING, INFORMATION AND CONFIGURATION MENUS – TRANSMITTER ............................... 5-4

5.4.1 Radio control group ........................................................................................................ 5-5

5.4.2 TX config group .............................................................................................................. 5-5

5.4.3 Interface config group .................................................................................................... 5-6

5.4.4 Bite system group ............................................................................................................ 5-7

5.4.5 System info group ........................................................................................................... 5-7

5.5 PARAMETER DETAILS – TRANSMITTER .................................................................................. 5-8

5.5.1 Radio control group ........................................................................................................ 5-8

5.5.2 TX config group .............................................................................................................. 5-8

5.5.3 Interface config group .................................................................................................. 5-11

5.5.4 Bite system group .......................................................................................................... 5-14

5.6 USER MENU – RECEIVER (RESTRICTED ACCESS LEVEL) ....................................................... 5-15

5.7 USER MENU – RECEIVER (DEFAULT ACCESS LEVEL)............................................................ 5-16

5.8 SETTING, INFORMATION AND CONFIGURATION MENUS – RECEIVER.................................... 5-17

5.8.1 Radio control group ...................................................................................................... 5-18

5.8.2 RX config group ............................................................................................................ 5-18

5.8.3 Interface config group .................................................................................................. 5-19

5.8.4 Bite system group .......................................................................................................... 5-20

5.8.5 System info group ......................................................................................................... 5-20

5.9 PARAMETER DETAILS – RECEIVER ....................................................................................... 5-21

5.9.1 Radio control group ...................................................................................................... 5-21

5.9.2 RX config group ............................................................................................................ 5-22

5.9.3 Interface config group .................................................................................................. 5-23

5.9.4 Bite system group .......................................................................................................... 5-26

6 ERROR CONDITIONS AND CORRECTIVE ACTIONS ..................................................... 6-1

6.1 TRANSMITTER ERROR CONDITIONS ........................................................................................ 6-1

6.2 RECEIVER ERROR CONDITIONS ............................................................................................... 6-5

7 LIST OF TABLES AND FIGURES .......................................................................................... 7-1

APPENDIX A. LIST OF MARITIME CHANNELS AND FREQUENCIES ............................ 7-1

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Introduction

Page 1-1

Model

P/N

Contain units

Output

Frequency
range

Modes

TR-7750C, Transceiver

X-84610

RA-7203C, TA-7650C,
PSU-7002

10 - 50 Watts

156-162 MHz

FM, (G3E)

TA-7650C, Transmitter

X-84555

TA-7650C,

PSU-7002

10 - 50 Watts

156-162 MHz

FM, (G3E)

RA-7203C, Receiver

X-84550

RA-7203C

N/A

156-162 MHz

FM, (G3E)

1 Introduction

1.1 Models covered by this manual

The following models / variants are covered by this operator’s manual

Table 1.1-1, Radio models

Throughout this manual the term transmitter unit, TX, TA-7650C refers to the transmitter unit.
The term transceiver, TR, TR-7750C refers to any variant of the transceiver unless specifically noted
in the text and the term receiver, RX and RA-7203C is used for the receiver unit.

1.2 Layout of the transceiver

The receiver unit, RA-7203C operates as an independent receiver. The transmitter unit TA-7650C
operates as an independent transmitter, but requires the power supply unit, PSU-7002 for operation
on AC power. The receiver and transmitter units may be placed in entirely different locations or
together when configured as a transceiver.

Figure 1.1, Complete Transceiver, RA-7203C, TA-7650C and PSU-7002

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Jotron AS| TR7750C: Operators Manual  Introduction

Page 1-2

1.3 Applications

The transmitter TA-7650C and the receiver RA-7203C can be used either as a standalone transmitter
/ receiver for maritime voice or data communication, or combined as a transceiver.
The transmitter / receiver can be operated in the following modes:

 Locally as an analogue FM transceiver, with microphone and headphone connected to the

front panel connector,

 Connected to a VCS (Voice Control System) using 600-ohm analogue lines for audio, together

with keying in form of in-band tones, external voltages or phantom keying.

 In addition the transmitter/receiver has a large range of options for remote control using

Ethernet, serial lines or front panel controls.

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Jotron AS| TR7750C: Operators Manual  Technical SPECIFICATIONS

Page 2-1

Standards

EN 301489-x ,Health and Safety: EN 60950,Radio specifications:EN301929-1 and EN301929-2,FCC part80

Environmental, all units

Temperature range

-20°C to +55°C (operating) -40°C to +70°C (storage)

Humidity

90% @+40°C (non condensing)

Shock

Transport: IEC-721-3-2, Class 2M3

Vibration

Transport: IEC-68-2-32, Class 2M3. IEC-68-2-6

EMC

EN 301 489 – part 22, FCC, IC

General, all units

FM 25 kHz

FM 12.5 kHz

DSC

Frequency range

156-162 MHz , All channels, simplex and duplex within the maritime VHF band is available.

Frequency stability

+/- 1.0 ppm

RF Modes

G3E

G3E

G2B

Keying time

< 1.0ms

< 1.0ms

< 1.0ms

Bit rate

2.4 kbit/s

Frequency response

300-3400 Hz

350-2500 Hz

Data ports

RS232, RS485, 100BaseT

Protocols

Simple Network Management Protocol (SNMP v.2), RS232, RS485; See Protocol description

BITE monitoring

VSWR, Voltages, Currents, Levels, Lock detect,

Temperature, Output power, Reflected power, a.o.

Supply voltage, AC

115/230VAC +15/-10% / 50-60Hz

Supply voltage, DC

21.6 - 31.2VDC negative ground

MTBF

>10 years / unit

MTTR

<30 minutes at lowest replaceable unit

Transmitter unit

FM 25 kHz

FM 12.5 kHz

DSC

Output power

10-50W

Adjacent channel power

>80dBc

>70dBc

>80dBc

Modulation level

up to ± 5kHz deviation

Distortion

< 3%

Line input

600, -36 - +7dBm

Intermodulation protection

>40 dB when interfering signal is decoupled with at least 30 dB

Tx timeout

10s to 5 min in 10s steps

Inband keying

Configurable tones: 150 – 3400Hz

VSWR

1 : Infinity

Duty cycle

100% continuous operation @ambient below 40°C

Power consumption

<280VA

Dimension Transmitter nit

142mm(28TE)(W) * 230mm(D) * 128mm (H), Weight 3.0 kg

2 Technical SPECIFICATIONS

2.1 General specification, Transceiver Units, TR-7750C

2.2 Transmitter Units, TA-7650C

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Receiver unit

FM 25 kHz

FM 12.5 kHz

DSC

Sensitivity, FM@1V/30% pd

10dB SINAD (CCITT)

Adjacent channel rejection

>80dB

>80dB

>70dB

Intermodulation (3 signal)

>80 dBc

IF bandwidth

+/- 11kHz

+/- 3.5 kHz

+/- 11 kHz

Image and IF frequency

>110 dB

Squelch operation

Adjustable -107dBm, 30dB

S/N + carrier override

Activation time <20ms

Hysteresis <3dB

Audio AGC

30% - 90%, <1dB variation

Signal / Noise

>45dB on any output @100V, 30%

AGC range

-107dBm to +5dBm

Inband squelch signal

User configurable tones: 150 - 3400 Hz

Line output

600, -36 - +7dBm @90% modulation

Harmonic distortion

<5% @90% AM (line output)

Cross modulation

>85dB @ 100 kHz frequency offset

Blocking

>100dB @1MHz offset,>110 dB out of band signals

Dynamic range

>110dB

Spurious response rejection

>90dB

Weight

1.7 kg

Dimension Receiver unit

71mm (14TE)(W) * 230mm(D) * 128mm (H)

Power supply unit

Supply voltage, AC

115/230VAC +15/-10% / 50-60Hz

Output voltage

+28 VDC regulated

DC throughput

When AC not present

Max load

10A average, 18A peak (300W)

Dimension PSU unit

71mm (14TE)(W) * 303mm(D) * 128mm (H)

Weight

1.3Kg

2.3 Receiver Unit, RA-7203C

2.4 Power Supply Unit, PSU-7002

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Jotron AS| TR7750C: Operators Manual  Functional description

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Navigation

button A

Display

Navigation

button B

Indicators:
OUT: Output power indicator
SWR: High SWR indicator

PTT button

Scroll / Select

Switch

ON/OFF

button

Navigation

button C

Indicators:
LOW: Transmits in low power
AL: Alarm active (red)
REM: Remote ready (green)
STBY: Standby (yellow)

Mic/Headset

connector

3 Functional description

3.1 Front Panel Controls, Transmitter unit

3.1.1 Display

The display shows the most important operational parameters; Channel, frequency and modulation.
In addition, the display will show several menus, submenus and operational parameters when
entering into the menu using Navigation button A.

3.1.2 Scroll/Select switch and Navigation buttons A, B and C

The navigation buttons, A, B and C, together with the Scroll/Select switch are used to navigate
through the menus.
The Scroll/Select switch has three actions: It can be turned clockwise, anti-clockwise, or momentarily
pressed.
In general the use of the navigation buttons are:

The user interface will indicate which navigation button to use.

3.1.3 PTT button

This button is used to immediately key the transmitter for test/measurement purposes, connected
together with the PTT line available on the microphone connector.

3.1.4 ON/OFF button

Press and hold button (for app. 2s) to switch unit ON or OFF.

Figure 3.1-1, Front view, transmitter unit, TA-7650C/25C/10C

A or Scroll/Select right: Increase a value (up)
B or Scroll/Select left: Decrease a value (down)
C or Scroll/Select press: Confirm or Enter.

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Jotron AS| TR7750C: Operators Manual  Functional description

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Mic/Headset connector

Name

PIN

Purpose

Mic input

1

Dynamic. Sensitivity 2.5mV nominal.

Mic GND

2

Reference input for mic signal

Headset

3

Headset output, contains sidetone and/or received
audio when used with a receiver (RA7203)

RS232

4

RS232 TX

RS232

5

RS232 RX

PTT 6 PTT input. Connect to GND (p.8) to key

+12VDC

7

+12 VDC to mic. Amplifier (10mA)

GND

8

Common ground

3.1.5 LED Indicators

LOW (yellow): The transmitter transmits in low power, either caused by an internal failure

(SWR, Temperature, or low input voltage) or set by the user. The low power
level is adjustable.

AL (red): Indicates that an alarm is present in the transmitter unit. Details of the alarm

will be shown on the display.

REM (green): This LED has multiple functions. The REMOTE indicator will be lit with a

constant green colour when the transmitter is “ready” for remote operation.
Ready means that the keying options has been set to include keying from an
external source, and that the voice input has been set to an external source
(600 ohm line input).
In addition the REMOTE indicator will flash yellow each time the unit is
communicating on either of the remote interfaces (RS232, RS485, Ethernet).

STBY (yellow): The transmitter is kept in standby, either by user input, an external signal to

the remote interface or because an alarm condition has been detected, and
the transmitter is set up as a MAIN transmitter. In standby the transmitter
will not be able to send, even if a valid key signal is input to the unit.

OUT (yellow): Indicate that the transmitter is keyed and power is being generated. The LED

is activated based on RF detected on the output of the power amplifier, thus
the LED gives an indication that power is generated.

SWR (red): Indicate that the SWR on the antenna is above the threshold value (app. 3:1).

The transmitter will reduce the output power to the predefined low power
level in order to protect the output stage.

3.1.6 Mic/Headset connector

Table 3.1-1, Mic/Headset connector, transmitter, pin out

The Mic/Headset connector is used for multiple purposes:

 Microphone/Headset connector:

Connect the microphone to the Mic input/Mic GND, the +12VDC can be used to power the
microphone or a microphone amplifier. The +12VDC is current limited at 100mA.
The Headset output (referenced to GND) contains the local sidetone generated from the
demodulated signal on the output of the transmitter when the transmitter is keyed, or the

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Jotron AS| TR7750C: Operators Manual  Functional description

Page 3-3

received audio if the transmitter is connected to a receiver using the T/R bus available on the
rear panels (for details see chapter 3.2.4)

 RS232 serial line

The RS232 serial line that can be used to control radio parameters from an external unit, or
to upload new firmware into the radio unit for future functionality. Details regarding
firmware upgrade is described in the maintenance and repair manual.

 Hardware key to change access level:

order to change the access level (see chapter 5.5.3 for details) a hardware
key must be inserted into the microphone/headset connector before
entering in to the menu system. The hardware key consists of a RJ45
connector where pin no. 4 and 5 (RS232 RX and TX) is connected together.

In

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3.2 Transmitter, rear connections

Figure 3.2-1, Rear view, transmitter unit, TA-7650C/25C/10C.

3.2.1 Antenna connector (50 ohm N)

Interface to the antenna cable for the transmitter or the transceiver when used together with a
receiver unit

3.2.2 Receiver ant. Connector (50 ohm BNC)

BNC-Type antenna output – 50 ohm. This connecor is connected to the antenna relay internally in
the transmitter unit and can be connected directly to the antenna input of a mating receiver unit
(RA7203).

3.2.3 DC input connector (Amphenol MS 3106A 10SL4S)(Jotron P/N: 96715)

Figure 3.2-2, Transmitter DC input connector, rear view

Connector for DC supply (21.6 - 31.2 VDC).
Connected to the mating power supply, PSU-7002, or to an external DC supply.
A is the positive (+) connection and B is the negative (-) connection points.

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Jotron AS| TR7750C: Operators Manual  Functional description

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LAN interface connector

Name

PIN

Purpose

LAN_TXP

1

Tx data

LAN_TXN

2

Tx data

LAN_RXP

3

Rx data

LAN_D3P

4

Optional

LAN_D3N

5

Optional

LAN_RXN

6

Rx data

LAN_D4P

7

Optional

LAN_D4N

8

Optional

AUX1 connector, transmitterAUX
Name

PIN

Purpose

ALARM_P

1

Alarm out-relay (NO)

ALARM_N

2

Alarm out-relay (NO)

Select_in_P

3

Select in, optocoupler input

RS232_S

4

RS232 Transmit data

RS232_R

5

RS232 Receive data

Select_in_N

6

Select in, optocoupler input

+12V

7

+12VDC output to external equipment (max 300mA)

GND

8

Common ground

3.2.4 LAN connector (RJ45)

This connector contains the Ethernet bus and is normally connected to a nearby switch/hub or
directly to a computer, using a screened twisted pair Ethernet cable.

Table 3.2-1, LAN interface connector, pin out

3.2.5 AUX1 CONNECTOR (RJ45)

This connector is normally connected to equipment used for remote control / remote supervision of
the transmitter.

Table 3.2-2, AUX1 connector, transmitter, pin out

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AUX2 connector, transmitter

Name

PIN

Purpose

KEY_OUT_P

1

Closed=Transmitting, optocoupler output

KEY_OUT_N

2

Closed=Transmitting, optocoupler output

MONITOR_P

3

Monitor output to tape recorder

TXLOW_P

4

Applying a voltage > 5VDC between pin 4 and 5
forces the transmitter into low power

TXLOW_N

5

Applying a voltage > 5VDC between pin 4 and 5
forces the transmitter into low power

MONITOR_N

6

Monitor output to tape recorder

TXKEY_P

7

Applying a voltage > 5VDC between pin 7 and 8 will
key the transmitter

TXKEY_N

8

Applying a voltage > 5VDC between pin 7 and 8 will
key the transmitter

REM connector, transmitter – Remote control of transceiver

Name

PIN

Purpose

RS485+

1

RS485 (+)

RS485-

2

RS485(-)

LINE_P

3

Diff. line input/output to TA/RA, 600 ohm

TX_KEY_G

4

Grounding this pin will key transmitter

RX_BUSY_OUT

5

RX Busy indicator output (squelch indicator)

LINE_N

6

Diff. line input/output to TA/RA, 600 ohm

ALARM

7

Low=Alarm (TA or TA/RA)

GND

8

Common ground

5

6

3.2.6 AUX2 connector (RJ45)

This connector is normally connected to equipment used for remote control / remote supervision of
the transmitter.

Table 3.2-3, AUX2 connector, transmitter, pin out

3.2.7 REM connector (RJ45)

This connector is normally connected to equipment used for remote control / remote supervision of
the transmitter. It contains the most basic interfaces used for remote control, and will in many cases
be the only connector used.
Note that this connector will also have the most basic functionality for remote controlling the
receiver when the Rx connector is connected to the REM connector on a receiver. In this case the
line, and squelch out signals from the receiver are reflected also on the REM connector.

Table 3.2-4, REM connector, transmitter, pin out

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Rx connector, transmitter. Interface to RX (transceiver config)

Name

PIN

Purpose

RS485+

1

RS485 (+)

RS485-

2

RS485(-)

LINE_P

3

Diff. line input from Receiver unit, 600 ohm

TX_BUSY

4

TX Busy indicator output (Mute output)

RX_BUSY

5

RX Busy optocoupler-input (Repeater key input)

LINE_N

6

Diff. line input from Receiver unit, 600 ohm

INT_ALARM

7

Low=Alarm (Note: I/O – low input will also be
recognized as an alarm (EXT))

GND

8

Common ground

3.2.8 Rx connector (RJ45)

This connector is normally connected to the REM connector on a mating receiver when used in a
transceiver configuration.
It gives functionality to a transceiver such as: Common 2 wire line interface, received audio in
transmitter local headset, transceiver alarm, TX/RX busy signalling when used as a VDL modem.

Table 3.2-5, Rx connector, transmitter, pin out

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Page 3-8

Navigation

button A

Display

Navigation

button B

Scroll / Select

Switch

ON/OFF

button

Sq / Navigation

button C

Indicators:
SQ: Squelch open (yellow)
AL: Alarm active (red)
REM: Remote ready (green)
STBY: Standby (yellow)

Headset

connector

Loudspeaker

3.3 Front Panel Controls, Receiver unit

3.3.1 Display

The display shows the most important operational parameters; Channel, frequency and modulation.
In addition, the display will show several menus, submenus and operational parameters when
entering into the menu using Navigation button A.

3.3.2 Scroll/Select switch and Navigation buttons A, B and C

The navigation buttons, A, B and C, together with the Scroll/Select switch are used to navigate
through the menus.
The Scroll/Select switch has three actions: It can be turned clockwise, anti-clockwise, or momentarily
pressed in.
In general the use of the navigation buttons are:

A or Scroll/Select right: Increase a value (up)
B or Scroll/Select left: Decrease a value (down)
C or Scroll/Select press: Confirm or Enter.

The user interface will indicate which navigation button to use.
Navigation button C is dedicated to squelch ON/OFF button in the default view.

3.3.3 ON/OFF button

To switch the unit ON or OFF: Press and hold button for approx 2s

3.3.4 LED Indicators

SQ (yellow): The receiver squelch is open (receiving audio) when lit.

Figure 3.3-1, Front view, receiver unit, RA-7203C

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Page 3-9

Mic/Headset connector

Name

PIN

Purpose

N/C 1 No connection

N/C 2 No connection

Headset

3

Headset output contains received audio.

RS232

4

RS232 TX

RS232

5

RS232 RX

N/C 6 No connection

+12VDC

7

+12 VDC to external amplifier (10mA)

GND

8

Common ground

AL (red): Indicates that an alarm is present in the receiver unit. Details of the alarm

will be shown on the display.

REM (green): This LED has multiple functions. The REMOTE indicator will be lit with a

constant green colour when the receiver is “ready” for remote operation.
Ready means that the audio is output to an external source (600 ohm line
input).
In addition the REMOTE indicator will flash yellow each time the unit is
communicating on either of the remote interfaces (RS232, RS485, Ethernet).

STBY (yellow): The receiver is kept in standby, either by user input, an external signal to the

remote interface or because an alarm condition has been detected, and the
receiver is set up as a MAIN receiver. In standby the receiver will not output
any audio on any audio interface.

3.3.5 Headset connector

Table 3.3-1, Headset connector, receiver, pin out

The Headset connector is used for multiple purposes:

 Headset connector:

The Headset output (referenced to GND) contains the received audio.

 RS232 serial line

The RS232serial line that can be used to control radio parameters from an external unit, or to
upload new firmware into the radio unit for future functionality. Details regarding firmware
upgrade is described in the maintenance and repair manual.

 Hardware key to change access level: In

order to change the access level (see chapter 5.5.3 for details) a
hardware key must be inserted into the microphone/headset connector before
entering in to the menu system. The hardware key consists of a RJ45
connector where pin no. 4 and 5 (RS232 RX and TX) is connected
together.

P/N: 84748 (G)

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3.4 Receiver, rear connections

Figure 3.4-1, Rear view, receiver unit, RA-7203C.

3.4.1 Antenna connector (50 ohm N)

Connect directly to a receiver antenna, or to the receiver antenna connector (BNC) on the
transmitter unit.

3.4.2 DC input connector (Amphenol MS 3106A 10SL4S)(Jotron P/N: 96715)

Figure 3.4-2, Receiver DC input connector, rear view

Connector for DC supply (21.6 - 31.2 VDC).
Connect to an optional external DC supply to operate the unit on DC or as a backup supply if the
main AC fails.
A is the positive (+) connection and B is connected to ground or chassis (-).

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LAN interface connector

Name

PIN

Purpose

LAN_TXP

1

Tx data

LAN_TXN

2

Tx data

LAN_RXP

3

Rx data

LAN_D3P

4

Optional

LAN_D3N

5

Optional

LAN_RXN

6

Rx data

LAN_D4P

7

Optional

LAN_D4N

8

Optional

AUX1 connector, receiver unit

Name

PIN

Purpose

ALARM_P

1

Alarm out-relay (NO)

ALARM_N

2

Alarm out-relay (NO)

Select_in_P

3

Select in, optocoupler input

RS232_S

4

RS232 Transmit data

RS232_R

5

RS232 Receive data

Select_in_N

6

Select in, optocoupler input

+12V

7

+12VDC output to external equipment (max 100mA)

GND

8

Common ground

3.4.3 LAN connector (RJ45)

This connector contains the Ethernet bus and is normally connected to a nearby switch/hub. It can
also be connected directly to a computer, using a twisted pair Ethernet cable.

Table 3.4-1, LAN interface connector, pin out

3.4.4 AUX1 CONNECTOR (RJ45)

This connector is normally connected to equipment used for remote control / remote supervision of
the receiver.

Table 3.4-2, AUX1 connector, receiver, pin out

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AUX2 connector, receiver unit

Name

PIN

Purpose

Squelch_out_P

1

Closed=Receiving (Sq open), optocoupler output

Squelch_out_N

2

Closed=Receiving (Sq open), optocoupler output

AGC_HILO_P

3

Hi/Lo output depending on signal strength,
optocoupler output

N/C 4

N/C 5

AGC_HILO_N

6

Hi/Lo output depending on signal strength

AGC_OUT

7

AGC analogue voltage output, depending on signal
strength. Referred to GND

N/C 8

Interface to Remote equipment or a transmitter unit

Name

PIN

Purpose

RS485+

1

RS485 (+)

RS485-

2

RS485(-)

LINE_P

3

Line output from Receiver unit, 600 ohm

TX_BUSY

4

TX Busy indicator input (Mute input)

RX_BUSY

5

RX Busy output

LINE_N

6

Line output from Receiver unit, 600 ohm

INT_ALARM

7

Low=Alarm (Note: I/O – low input will also be
recognized as an alarm (EXT))

GND

8

Common ground

5

6

3.4.5 AUX2 connector (RJ45)

This connector is normally connected to equipment used for remote control / remote supervision of
the transmitter.

Table 3.4-3, AUX2 connector, receiver, pin out

3.4.6 REM connector (RJ45)

This connector is normally connected to a mating transmitter unit (RX connector) when used in a
transceiver configuration, or to other equipment used for remote control of the receiver.

When connected to a transmitter, the connector gives “transceiver” functionality to the transmitter

and contains necessary signals for audio and control. The TX_BUSY and RX_BUSY signals are also used
in data modes to signal that the transmitter or receiver is busy transferring data.

Table 3.4-4, REM connector, receiver, pin out

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Indicators:
AC: Operating on AC
ON: ON (DC output)

3.5 PSU-7002, Power Supply Unit, frontview

Figure 3.5-1, PSU-7002, front view

3.5.1 LED Indicators

AC (yellow): Indicates that AC is present, and that the unit currently is operating on the

main AC power supply.

ON (green): Indicates that the PSU is ON and delivers DC on its output.

The DC is either derived from the main AC input (shown by the AC indicator),
or from the backup DC input (AC indicator dark).

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3.6 Power Supply Unit rear connectors.

Figure 3.6-1, Power supply unit - rear view

3.6.1 DC input connector (Amphenol MS 3106A 10SL4S)(Jotron P/N: 96715)

The DC input is connected to the DC backup supply (if available).
Input range is 21.6 - 31.2 VDC and current consumption is max 9A average when the transmitter
operates with full power output (50W).
A is the positive (+) connection and B is connected to ground (-).

Figure 3.6-2, DC input connector, PSU

3.6.2 DC Output Connector(Amphenol MS 3106A 12S3P)(Jotron P/N: 93697)

The DC output connector is connected to the transmitter unit and contains the +28V DC supply for
the transmitter. The DC is generated from the main AC input or the DC backup input.

Figure 3.6-3, DC output, PSU

A is the positive connector pin (+) and B is connected to ground (-).

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3.6.3 AC Input connector

Input for external AC.
AC is input between A and C, B is chassis ground.
The voltage range is from 85 to 250 VAC

Figure 3.6-4, AC input connector, PSU

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Page 4-1

Procedure

Reference

1

Initial inspection

4.2 2 Install equipment into 19” sub racks (equipment cabinet)

4.3

3

Connect chassis stud to system earth or cabinet

Figure 3.2-1 (TX)
Figure 3.4-1 (RX)

Figure 3.6-1
(PSU)

4

Connect remote connectors as required

4.6 5 Connect antenna connectors

4.4 6 Connect DC supply (if required)

4.5 7 Connect AC supply (if required

4.5

Items included for a TA-7650C transmitter

P/N

1

Radio unit TA-7650C

1

84555

2

Power supply unit PSU-7002

82417

3

Interconnecting cord between TA and PSU

81725

4

CD with Operators guide

84417

5

DC connector

96715

6

AC power cord

92375

Items included for a RA-7203C receiver

P/N 1 Radio unit RA-7203C

84550

2

CD with Operators guide

84417

3

DC connector

96715

4

AC power cord

92375

4 Installation

4.1 Introduction.

The procedures for installing the radio units / transceiver are described in table 4.1 below.
It is recommended that these procedures are completed in the order shown.

Table 4.1-1, Installation procedures

4.2 Initial inspection

On receipt of the radio units, remove all transit packaging and check that there is no damage to the
equipment. If damage is evident, contact Jotron immediately and retain the original transit
packaging.

1

Variants may include: - Reduced maximum power level <50 W

- PM modulation

- Frequency range 156 – 162MHz

- Inband ptt signalling (option: 84358)

- Inband squelch signalling (option: 84358)

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4.3 Installation into equipment cabinet

The units may be installed into a standard 19” subrack with a height of 3U.
The total subrack is divided into 84 TE units. The transmitter occupies 28 TE, the PSU occupies 14TE
and the receiver unit occupies 14TE.
For a transceiver this leaves a free space of 28TE available for other equipment.
Figure 4.3-1 shows some examples for installation into 19” subrack. From top to bottom the figure
shows: 6 receivers in one subrack, 2 transmitters with PSU in one subrack and 3 transmitters without
PSU (operated on DC) in one subrack.

Figure 4.3-1, Examples of various configurations

4.4 Antenna connectors

The antenna should be of good quality with regards to gain and VSWR to obtain maximum
performance. Recommended antennas can be Procom CXL-2-1LW/H (0dBd), Procom CXL-2-3C/M
(3dBd) or similar. Make sure that the VSWR on the antenna is low, and that the cable from the
transmitter to the antenna is of good quality to avoid mismatch and unnecessary losses. The antenna
used with this radio should be installed at least 260cm away from any area where people are likely to
be.
A cable loss of 1 dB is the same as reducing the power output of a 50W transmitter to less than 40W.
Similarly, a cable loss of 2 dB is the same as reducing the output power to less than 32W.

In areas were thunderstorms and lightning is a problem, surge arrestors should be mounted between
the antenna connector and the antenna cable. The arrestors should be of good quality and be
capable of handling the output power of the transmitter.

The antenna output of the transmitter is an N-type antenna connector on the back of the
transmitter. The second connector (BNC-type) is the output of the antenna switch and can be used to
connect the input of a receiver.

4.5 AC and DC connectors

Refer to section 3.4.2, 3.6.1 and 3.6.3 for voltages and connectors.

4.6 Remote signals

Several remote signals are available on the rear interfaces of the radio units.
These signals can be grouped into: Audio signals, Key signals, Data interface signals and other signals.
Note, for all interface signals, RJ45 connectors are used. As far as practically possible, the pairs used
on a standard ethernet connection are used when a signal is input/output as a pair to the radio (e.g.
audio lines). For interconnections between the transmitter and receiver, and for interconnection to a

P/N: 84748 (G)

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Page 4-3

TX - REM/RX RX - REM PIN NAME DESCRIPTION

Pin no Pin no

1 1

RS485+

RS485 - serial communication

2 2

RS485-

RS485 - serial communication

3 3

LINE_P

RX Audio 600ohm balanced

4 4

TX BUSY

TTL L=transmitting (RX pullup)

5 5

RX BUSY

TTL L=receiving (TX pullup)

6 6

LINE_N

RX Audio 600ohm balanced

7 7

ALARM

Alarm (TTL) I/O TRX alarm

8 8

GND

Ground

CABLE

4 pairs

RJ45 - Cat 5E, FTP

distribution panel with RJ45 connectors, standard Cat5E, ethernet cable should be used. This is a
good quality, screened cable, with 1 to 1 connections between the two connectors.
Below is an overview of the signals available and their primary use. Refer to chapter 3.2 and 0 for and
overview of the different connectors.

4.6.1 REM connector (receiver) and RX connector (transmitter)

Table 4.6-1, Transceiver, transmitter – receiver interconnections

The RX connector on the transmitter unit has a special function, and is normally used only in a
“transceiver” configuration.
When connecting the signals on the transmitter RX connector with the signals on the receivers REM
connector, the following functionality is added to the transmitter and receiver:

 The receiver audio line (p.3 and p.6) is input to the transmitter.

This enables the possibility to monitor the audio from the receiver from the transmitter
headphone connector, allowing only one plug to be used for a combined
headset/microphone.
In addition, it enables the possibility to use a 2 wire interface to the transmitters audio input
line for the combined transmitter and receiver audio.
Finally, it enables the functionality to monitor both the transmitted audio and the received
audio on the monitor output (TA-AUX2) line on the transmitter.

 A RX Busy signal (p.5) is input to the transmitter from the receiver.

This signal signals the transmitter that the RX is busy. This is used in VDL operation.

 A TX Busy signal (p.4) is output from the transmitter to the receiver.

This signal signals the receiver that the TX is busy (transmitting). This is used in VDL
operation, and to mute the receiver while transmitting (see table below).

 A receiver alarm in/out is connected to the transmitter alarm in/out.

This enables the functionality that the complete transceiver (both receiver and transmitter
unit) will enter into alarm state if one of the units fails. This is useful if the complete
transceiver should be switched to a backup transceiver.

 The RS485 serial lines from both units are connected in parallel.

This is useful to have only one connection point for the RS485 on the transceiver for remote
control.

P/N: 84748 (G)

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Page 4-4

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Installation

Page 4-5

Menu path:
Interface config ►

Parameter

Range

Default

Details

RS485
(TX and RX)

Bitrate

1200 – 115200

1200

Set the bit rate to use on the RS485 port

RS485
(TX and RX)

Address

1 – 255

1

Set the address to use on the RS485. In a
remote system using the RS485
communication port, all units that are
interconnected need to have a unique
address in order to avoid collisions and
misinterpretation of data.

RS485
(TX and RX)

Protocol

Legacy |
standard

Legacy

The protocols are described in the data
manual.
Legacy uses a protocol where the 9. bit is
used for address recognition, this is the
protocol used on the previous radio models
(TA7450, RA7202) and is compatible with
the RACS II PC software and the RCU
remote control unit.
Standard is an eight bit protocol that uses
the multidrop capability of the RS485 bus.
For more information on protocols, refer to
the SW manual.

Menu path:
RX config ►

Parameter

Range

Default

Details

Audio
( RX)

Mute on transmit

False | True

True

Set this to true if the receiver should be
muted while transmitting. Requires that the
Tx busy signal on the transmitters RX
connector is routed to the TX busy input on
the receiver REM connector. (p.4)

Table 4.6-2, Settings associated with the transmitter - receiver interconnection

P/N: 84748 (G)

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Page 4-6

Menu path:
TX config ►

Parameter

Range

Default

Details

Audio
(TX)

Monitor output

Headset |
Monitor output

Monitor
output

Set where the monitor output signal and the
received audio (if a receiver is connected) is
routed.
Can be set to the headset connector, the 600
ohm monitor line output or both.
The monitor signal is the demodulated signal
detected on the output of the transmitter.

Audio
(TX)

Monitor level

-80 – 10 dB

-50 dB

Set the relative output level of the monitor
signal. 10dB = max output, -80dB=minimum

4.6.2 Audio in/out and Line loop keying

Figure 4.6-1, the following audio remote signals are available on the rear connectors:

 Monitor out: Monitor signal, usually connected to a recording unit.

Table 4.6-3, Settings associated with MONITOR OUTPUT (TA – AUX1)

Figure 4.6-1, Audio interfaces on the transmitter and receiver units

With reference to

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Installation

Page 4-7

Menu path:
TX config ►

Parameter

Range

Default

Details

Audio
(TX)

Input source

Auto | Line | Mic
| modgen | VoIP

Auto

The input source determines where the audio
is applied to the transmitter.

 Auto: Uses line input for when a

key signal is detected on one of
the remote connectors and mic
input if the key signal is detected
on the front panel connector.

 Line: Uses the 600 ohm line

interface as the audio source

 Mic: Uses the microphone input as

the audio source

 Modgen: Uses the internal

modgen as audio input source – se
also Modgen frequency

 VoIP: Uses the IP interface as the

audio source (availability depends
on radio specifications).

Audio
(TX)

Line sensitivity

-40 – 0 dBm
1 dB steps

-17 dBm

Set the sensitivity of the 600 ohm line input.
This setting determines where the VOGAD
(automatic gain control) start to operate.
Thus if it is set to -17 dBm, levels above -17
dBm will be modulated with 85% (default
setting).
For levels below -17 dBm the modulation will
decrease linearly.

Audio
(TX)

Line termination

OFF | 600 ohm

600 ohm

Set the termination of the input line to either
OFF or 600 ohm. Normally this is set to 600
ohm, but can be set to OFF on one of the
radios, if two transmitters are connected in
parallel. This is to maintain the 600 ohm
impedance on the lines.

Audio
(TX)

Line mute level

OFF or

-40 to -10dBm
1 dB steps

OFF

Below this level, the line input will be muted.
Used where noisy lines are connected to the
transmitter to avoid unnecessary noise on
the produced RF signal during periods of
silence (Automatic transmissions; VOLMET,
ATIS)

Keying
(TX)

Source

Mic, line, txkey,
txgnd, inband

Mic, txkey

Determines what signal that will be used as
the source for keying the transmitter.
Any combinations can be set

 Mic: Local PTT input from a

microphone, where the PTT is
connected to pin 4 and 8(gnd) on
the Mic/headset connector.

 Line: Keying from a phantom

signal on the line input. Pin 3 and 6
on the Rem/TR connector.

 Txkey: The transmitter is keyed by

an external voltage on the
TXKEY_P and TXKEY_N input
pins. Signals located on Pin 7 and
8 on the | connector.

 Txgnd: The transmitter is keyed by

a signal on the TXKEY_G input pin
Signals are located on Pin 4 and 8
(gnd) on the REM/TR connector.

 Inband: The transmitter is keyed

using an inband tone (see also
inband frequency and inband
sensitivity)

 Line input, transmitter: This is the transmitter audio line input. This signal is usually

connected to a VCS system or a remote control that uses a 600 ohm line interface.

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Installation

Page 4-8

Menu path:
TX config ►

Parameter

Range

Default

Details

Keying
(TX)

Loop key bias

+12V, Gnd,
floating

Floating

Connects the center pin of the line input
transformer to:

 Floating: The center pin is not

connected. If loop keying is used,
an external voltage must be
applied to pin 3 (REM connector)
in order to key the transmitter

 Gnd: The center pin is grounded. If

loop keying is used, an external
voltage must be applied to pin 3
(REM connector) in order to key
the transmitter.

 +12V: A 12V DC is supplied on pin

3(REM/TR connector). The
transmitter can be keyed with a
relay (or equivalent) that create a
DC path on the line input pin, pin 3
and 6 (REM/TR connector).

Menu path:
RX config ►

Parameter

Range

Default

Details

Audio
(RX)

Output source

Speaker |
Headphone |
Lineout |
VoIP

Speaker,
Headphone,
Lineout

The output source determines where the
received audio is output.

 Line: Output audio on the 600

ohm line interface

 Speaker: Output audio on the

integrated speaker.

 Headphone: Output audio to a

headphone connected to the front
panel connector.

 VoIP: Output audio on the IP

interface (availability depends on
radio specifications).

Audio
(RX)

Line output level

-40 to +10 dBm
1 dB steps

-10 dBm

Set the maximum output level on the 600
ohm line output.

Table 4.6-4, Settings associated with LINE_INPUT (TX-REM)

 Line output, receiver: This is the receiver audio line output. This signal is usually connected

to the VCS system or a remote control that uses a 600 ohm line interface.

Table 4.6-5, Settings associated with LINE_OUTPUT (RX-REM)

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Installation

Page 4-9

4.6.3 Other key signals

Figure 4.6-2, Key signals on the transmitter unit

In addition to the line loop keying, it is possible to key the transmitter, using several other hardware
and software options.

 TX_KEY_G

This is a signal available on the transmitter REM connector, pin 4. This signal, if connected to
GND will key the transmitter.

 TXKEY_P, TXKEY_N

This is a differential signal, available on the transmitter AUX2 connector, pin 7 and 8. This
signal will key the transmitter if a voltage between 12 and 48 V is fed between them. Note
also that this is a differential signal, not connected to any ground potential inside the
transmitter, therefore the signal can be configured for both positive and negative voltage
keying (see figure).

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Installation

Page 4-10

Menu path:
TX config ►

Parameter

Range

Default

Details

Keying
(TX)

Source

Mic, line, txkey,
txgnd, inband

Mic, txkey

Determines what signal that will be used as
the source for keying the transmitter.
Any combinations can be set

 Mic: Local PTT input from a

microphone, where the PTT is
connected to pin 4 and 8(gnd) on
the Mic/headset connector.

 Line: Keying from a phantom

signal on the line input. Pin 3 and 6
on the Rem/TR connector.

 Txkey: The transmitter is keyed by

an external voltage on the
TXKEY_P and TXKEY_N input
pins. Signals located on Pin 7 and
8 on the | connector.

 Txgnd: The transmitter is keyed by

a signal on the TX_KEY_G input
pin Signals are located on Pin 4
and 8 (gnd) on the REM/TR
connector.

 Inband: The transmitter is keyed

using an inband tone (see also
inband frequency and inband
sensitivity)

Table 4.6-6, Key Source settings

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4.6.4 Squelch and AGC signals, receiver unit

Figure 4.6-3, Squelch and AGC signals receiver unit

 RX_BUSY (REM, p.5)

Squelch output signal that is referenced to GND.
This signal can be used to detect that the receiver is busy on a connected transmitter unit, on
a remote control or an other unit that can use this signal.
The signal polarity can be configured.

 SQUELCH (AUX2, p.1 and p.2)

This signal indicates that the squelch is activated / closed.
The polarity can be configured. The output is a solid state relay, rated for maximum 100V /
100mA.

 AGC_HILO_P, AGC_HILO_N (AUX2, p.3 and p.6)

This signal indicates that a signal above approximately +40 dBuV is received.
This can be used to detect if the signal comes from a collocated transmitter operating on the
same frequency or a transmission from an aircraft.

 AGC VOLTAGE (AUX2, p.7)

This is an analogue output 0-5V. The output voltage is 0V for an input of xxx uV and increases
linearly with the input signal up to xxx uV where the voltage reach +5V.

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Menu path:
RX config ►

Parameter

Range

Default

Details

Squelch

SqOut output

Closed | Open |
Closed on busy|
Open on busy

Closed on
busy

Set the behavior of the SqOut output (AUX2,
pin 1 and pin 2).

Squelch

RxBusy output

Closed | Open |
Closed on busy|
Open on busy

Closed on
busy

Set the behavior of the RxBusy output
(REM, pin 5).

Table 4.6-7, Squelch output configuration

4.6.5 Alarm and Select signals transmitter and receiver

The alarm signals are outputs used to signal that the radio units has detected an alarm internally. The
Select signal is used to select or deselect (inhibit) a particular unit. By deselecting a unit, the unit will
enter into standby and can not be used for radio communication. However, all other functionality of
the radio units is operational when the radio is in the standby state.
The pinout and signals are equal on the transmitter and the receiver unit, except the ALARM (REM,
p.7) pin. This pin has a fixed +5V pull-up on the receiver, while the pull-up is configurable on the
transmitter.

Figure 4.6-4, Alarm and select signals, transmitter

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Menu path:
Interface
config ►

Parameter

Range

Default

Details

Alarm config
(TX and RX)

Alarm pin pull-up

Disabled |
Enabled

Enabled

The ALARM_OUT_P and ALARM_OUT_N
output pins on AUX1 is used to signal that
the radio has an alarm. This parameter
applies a pull up voltage to ALARM_OUT_P
when there are no alarms present. When an
alarm is detected the relay contact close.

Alarm config
(TX and RX)

Select polarity

High | Low

Low

The SELECT_IN_P and SELECT_IN_N
input pins on AUX1 can be used to select /
deselect (Standby) the radio with an
external signal (e.g. alarm from a main
radio). This setting determines if the radio
should be operational on a low select input
signal or a high select input signal.

 ALARM_P, ALARM_N (AUX1, pin 1 and 2)

This is a differential signal, used to signal the alarm state. The radio can be set up with an
internal pull-up to +12V if desired.

 ALARM (REM, pin 7)

Same as the signal above, but this signal is referenced to GND.

 SELECT (AUX1, pin 3 and 6)

This input is connected to an optocoupler. The SELECT requires an external voltage to
operate.
One way to use the SELECT signal is in conjunction with the ALARM output signal from
another radio unit. If the ALARM signal (ALARM_P and ALARM_N) on a primary (main) radio
is connected to the SELECT_P and SELECT_N on a secondary (backup) radio, then automatic
switchover from the main to the standby radio is performed when the main radio detects an
alarm. In this mode, a pull-up is required on the ALARM output from the primary radio.

Table 4.6-8, Alarm and Select settings, transmitter and receiver

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Menu path:
Radio control
►

Parameter

Range

Default

Details

4.6.6 Miscellaneous signals, transmitter

Figure 4.6-5, Misc signals, transmitter

 RX BUSY (SQ) (REM, pin 5)

This signal is only available when a receiver is connected with a 8 pin bus between the
transmitter RX and the receiver REM connector.
The signal is the same as the RX BUSY from the receiver, settings are done on the receiver
unit.

 KEY_OUT_P, KEY_OUT_N (AUX2, pin 1 and 2)

This output can be used for external equipment that needs a key signal from the transmitter.
The key signal is available immediately after a key input is received on any of the key inputs.
Normally RF is produced only a few ms (<10ms) after a key signal is applied to the
transmitter.
If the KEY_OUT is used for external equipment that used relays for switching the RF, it is
necessary to delay the RF output, this can be done with a software setting, see below.

 TXLOW_P, TXLOW_N (AUX2, pin 4 and 5)

This input is used to immediately switch the transmitter into low power. The input requires
an external pull-up to work. The low power level can be adjusted with a software setting.

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Menu path:
Radio control
►

Parameter

Range

Default

Details

Low power level
(TX)

30 – 41 dBm
1 dB steps

41 dBm

Set the low power level of the transmitter in 1
dB steps. The low power level is the output
power of the transmitter when the transmitter
is set to low power, either by a command or
by an external input signal.
30 dBm corresponds to 1W output, 41 dBm
is 12W ouput.

Menu path:
TX config ►

Parameter

Range

Default

Details

Keying
(TX)

RF delay

0 – 200 ms

0 (OFF)

This setting is useful when the transmitter is
used together with external equipment such
as T/R relays, power amplifier or other
equipment that includes RF switchover
relays.
Since the RF switching in the transmitter is
done electronically, the RF is produced in
less than 10ms after the PTT signal is
detected. It could be harmful for the external
relays if the RF is applied to them before
switchover has occurred.
In order to delay the RF carrier this
parameter should be used under such
circumstances. A reasonable setting should
be in the order of 40-50 ms.

Table 4.6-9, Misc. settings, transmitter.

4.7 Applications

4.7.1 Transceiver, local configuration

In a transceiver setup for local configuration, the mic and headset signals are interfaced to the
microphone/headset connector on the transmitter. The headphone signal can also be derived from
the headset connector on the transmitter.

Connection for local operation is shown in

Figure 4.7-1 and tab.

Figure 4.7-1, Transceiver, Local configuration, interfacing

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Step

Description

Reference

1

Connect an 8 wire Cat5e cable between TA-RX connector and RA­REM connector.

4.6.1 - Pin description

2

Set the Mute on transmit to enabled (receiver)

5.9.2 - RX config group

3

Set Audio output source to Lineout (receiver)

5.9.2 - RX config group

4

Set Audio input source to mic (transmitter)

5.5.2 – TX config group

5

Set Monitor output to headset (transmitter)

5.5.2 – TX config group

6

Set Keying source to include mic (transmitter)

5.5.2 – TX config group

7

Connect a coax cable (RG58 or better) between the TA – Receiver
antenna connector (BNC) and the antenna input on the receiver.

Alternatively, use separate antennas for the TA and RA.

3.2.2 and 3.4.1

Other useful signals in Local configuration:

AUX1

Alarm out, Select in, RS232, +12V

3.2.5 (transmitter AUX1) and

3.4.4 (receiver AUX1)

TA­AUX2

Key out relay, Monitor output, TX_LOW (Gas alarm) input, TXKEY

3.2.6 (transmitter AUX2)

RA-

AUX2

Squelch out relay, AGC HILO output, AGC voltage output

3.4.6 (receiver AUX2)

TA –
REM

RS485, Line input, Key, Squelch, Alarm

3.2.7 (transmitter REM)

Table 4.7-1, Transceiver, Local configuration

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Step

Description

Reference

1

Connect an 8 wire Cat5e cable between TA-RX connector and RA­REM connector.

4.6.1 - Pin description

2

Set Mute on transmit to enabled (receiver) – if desired

5.9.2 - RX config group

3

Set Audio output source to Lineout (receiver)

5.9.2 - RX config group

4

Set Audio input source to line (transmitter)

5.5.2 – TX config group

5

Set Keying source to include txkeygnd

5.5.2 – TX config group

6

Connect a coax cable (RG58 or better) between the TA – Receiver
antenna connector (BNC) and the antenna input on the receiver.

Alternatively, use separate antennas for the TA and RA.

3.2.2 and 3.4.1

Other useful signals in Remote configuration:

AUX1

Alarm out, Select in, RS232, +12V

3.2.5 (transmitter AUX1) and

3.4.4 (receiver AUX1)

TA­AUX2

Key out relay, Monitor output, TX_LOW (Gas alarm) input, TXKEY

3.2.6 (transmitter AUX2)

RA-

AUX2

Squelch out relay, AGC HILO output, AGC voltage output

3.4.6 (receiver AUX2)

TA –
REM

RS485, Line input, Key, Squelch, Alarm

3.2.7 (transmitter REM)

4.7.2 Transceiver, remote configuration

In a transceiver setup for remote configuration, the audio is fed into the transmitter and the received
audio is output from the receiver on the 600 ohm lines.
The line can either be a 2 wire (2W) audio line connected to the transmitter only, or a 4 wire (4W)
interface connected to the transmitter and the receiver units.

Figure 4.7-2, Transceiver, Remote configuration with 2 wire audio interface

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Step

Description

Reference

1

For audio line interfaces refer to the reference

4.6.2 – Audio interface

3

Set Audio output source to Lineout (receiver)

5.9.2 - RX config group

4

Set Audio input source to line (transmitter)

5.5.2 – TX config group

5

Set Keying source to include txkeygnd ( or other signal if
desired)

5.5.2 – TX config group

6

Connect a coax cable (RG58 or better) between the TA – Receiver
antenna connector (BNC) and the antenna input on the receiver.

Alternatively, use separate antennas for the TA and RA.

3.2.2 and 3.4.1

Table 4.7-2, Transceiver, Remote (2W) interface

Figure 4.7-3, Transceiver, Remote configuration with 4 wire audio interface

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Step

Description

Reference

Other useful signals in Remote configuration:

AUX1

Alarm out, Select in, RS232, +12V

3.2.5 (transmitter AUX1) and

3.4.4 (receiver AUX1)

TA­AUX2

Key out relay, Monitor output, TX_LOW (Gas alarm) input, TXKEY

3.2.6 (transmitter AUX2)

RA-

AUX2

Squelch out relay, AGC HILO output, AGC voltage output

3.4.6 (receiver AUX2)

TA –
REM

RS485, Line input, Key, Squelch, Alarm

3.2.7 (transmitter REM)

Table 4.7-3, Transceiver, Remote (4W) interface

4.7.3 Transmitter, main / backup configuration

By connecting the alarm output from one (main) transmitter to the select input on a backup unit, it is
possible to perform automatic switching between them. In this way, if a main transmitter detects an
internal failure, it can be set up to enter into standby mode and stop transmissions. The alarm signal
will also signal to a backup unit to take over the transmit function.

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Step

Description

Reference

1

Connect the alarm_out signal (p.1,2) from AUX1 on the main
transmitter to the select_in signal (p.3.6) on AUX1 on the standby
transmitter. The connection can be done via a distribution panel or
by making a special with RJ45 connectors in each end. The cables
used should be of the same quality as a CAT5E network cable and
the screen should be connected in the plugs.

3.2.5 – AUX1 connector

2

Set Alarm config, Alarm pin pullup to Enabled (default)

5.5.3 – Interface config group

3

Set Alarm config, Select polarity to Low (default)

5.5.3 – Interface config group

4

Set the main transmitter Operation mode to Main

5.5.1 – Radio control group

5

Set the backup transmitter Operation mode to Norm (default)

5.5.1 – Radio control group

6

Connect separate antennas to the two transmitters.

Alternatively use an external antenna change over unit (ACU) in
order to switch the antenna between the main and standby
transmitters. The antenna change over unit can be controlled by
the alarm signal on the main unit

Figure 4.7-4, Main / Backup transmitter

Table 4.7-4, Main/backup configuration, transmitters

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Step

Description

Reference

1

Connect the alarm_out signal (p.1,2) from AUX1 on the main
receiver to the select_in signal (p.3.6) on AUX1 on the standby
receiver. The connection can be done via a distribution panel or by
making a special with RJ45 connectors in each end. The cables
used should be of the same quality as a CAT5E network cable and
the screen should be connected in the plugs.

3.4.4 – AUX1 connector

2

Set Alarm config, Alarm pin pullup to Enabled (default)

5.8.3 – Interface config group

3

Set Alarm config, Select polarity to Low (default)

5.8.3 – Interface config group

4

Set the main receiver Operation mode to Main

5.8.1 – Radio control group

5

Set the backup receiver Operation mode to Norm (default)

5.8.1 – Radio control group

6

Connect separate antennas to the two receivers.

Alternatively use an external antenna change over unit (ACU) in
order to switch the antenna between the main and backup
receivers. The antenna change over unit can be controlled by the
alarm signal on the main unit.

The antenna connection can also be done via a pair of
main/backup transmitters.

4.7.4 Receiver, main / backup configuration

By connecting the alarm output from one (main) receiver to the select input on a backup unit, it is
possible to perform automatic switching between them. In this way, if a main transmitter detects an
internal failure, it can be set up to enter into standby mode and stop reception of signals. The alarm
signal will also signal to a backup unit to take over the receive function.

Figure 4.7-5, Main / Backup receiver

Table 4.7-5, Main/backup configuration, receivers

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5 Operating Instructions

5.1 Introduction

To set up the transmitter and receiver units, several parameters can be selected from the
front panel. This section details how this is done and the range of all parameters.
Since the radio units contains no manual tuning points or switches, all parameters can in
principal be set from the front panel, however except in some rare occasions, most
parameters should be left at their default (factory preset) values.
There are 4 user levels that can be selected to limit the user access to certain parameters.
The user levels can be set on one of the data interface ports. There is also a way to override
the user levels, described in the technical manual.
These user levels are:

 Restricted Limits front panel operation to selecting preset channels and adjusting

audio output levels and display appearance. Use this level when the
radio units are used from a remote position or in cases where the
user should be restricted to use preset channels only (1 – 100).

 Operation Same as restricted, but in addition the local user has full access to

changing and storing frequencies, and to change the squelch level.

 Technician This level gives the local user access to the most used installation

specific parameters (line levels, output power, etc.) and should be
used when installing or maintaining the radio units.

 SysOp This level gives unlimited access to all parameters within the radio

units and should be used with care.

In the following section, these symbols and abbreviations are used to explain navigation in
menus / setting of values:

 Scroll/Select switch =
 Navigation button A (left button) =
 Navigation button B (middle button) =
 Navigation button C (right button) =
 Clockwise = CW
 Counter Clockwise = CCW

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Display

Description

When the transmitter is switched on, it will show the channel, the
frequency and the operation mode (FM).

Press to navigate to the channel recall screen.
Select any channel (up to 100) that is previously stored in the radio by
rotating . Recall selected channel with
If no channel is stored, the display will show: CH: No channels

Press to navigate to the audio output level screen.
This setting adjusts the audio level output at the front panel
microphone/headset connector.
Rotate CW or CCW to adjust the headset level.

Press to navigate to the display intensity adjust screen.
This setting adjusts the intensity of the display and LED indicators.
Rotate CW or CCW to adjust the intensity.
Press to return to the default screen

Pressing from the main display will bring up the menu options
available for the current user level.

Menus for user level: Restricted
For details regarding submenus, refer to chapter 5.4.

5.2 User menu – transmitter (Restricted access level)

Main display window in restricted mode.

Table 5.2-1, User menu selections transmitter - restriced access level

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Display

Description

When the transmitter is switched on, it will show the channel, the
frequency,and the operation mode (FM).

Press to navigate to the channel recall screen.
Select any channel (up to 100) that is previously stored in the radio by
rotating . Recall selected channel with
If no channel is stored, the display will show: CH: No channels

Press to navigate to the audio output level screen.
This setting adjusts the audio level output at the front panel
microphone/headset connector.
Rotate CW or CCW to adjust the headset level.

Press to navigate to the channel select screen.
Select channel number by rotating CW or CCW.
Confirm new channel with or .

Confirm with or .
If the channel is already programmed, the channel may be cleared using

Press to navigate to the display intensity adjust screen.
This setting adjusts the intensity of the display and LED indicators.
Rotate CW or CCW to adjust the intensity.
Press to return to the default screen

Pressing from the main display will bring up the menu options
available for the current user level.

Menus for user level: Operator
For details regarding submenus, refer to chapter 5.4.

Menus for user level: Technician
For details regarding submenus, refer to chapter 5.4.

Menus for user level: SysOp
For details regarding submenus, refer to chapter 5.4.

5.3 User menu – transmitter (Default access level)

Main display window for user levels: Operator, Technician and SysOp.

Table 5.3-1, User menu selections transmitter- Operator, Technician and SysOp access levels

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Submenu

Access level

Description

Radio control
►

SysOp, Technician

Access to operation mode, low power level, climax offset
parameters, modulation and standby settings.

TX config
►

SysOp

Access to configuration parameters for modulation, audio
settings, key (PTT) settings and internal calibration
settings.

Interface config
►

SysOp

Access to configuration parameters for the ethernet interface,
RS232 port, RS485 port, various pin settings on the hardware
interface (remote connectors) and the user access level.

Bite system
►

SysOp, Technician

Displays information about active alarms and gives the
user access to internal measurements.

System info
►

All

Displays information about the firmware and hardware
release, system up-time and radio identification

5.4 Setting, information and configuration menus – transmitter

Under the menu selection from the user menu, various submenu groups are available depending on
the user level.
The submenus and details for them are shown in the tables below.

Table 5.4-1, Submenus available on the transmitter

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5.4.1 Radio control group

SysOp and Technician access levels. Refer to section 5.5.1 for details.

Figure 5.4-1, Radio control group, transmitter

5.4.2 TX config group

SysOp access level. Refer to section 5.5.2 for details.

Figure 5.4-2, TX config group, transmitter

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Access control

Set the user

access level for

local operation

LAN

Set parameters for

ethernet (IP)

communication. IP

address, ports to

use, Gateway, etc.

RS232

Set parameters for

RS232 serial

communication.

Bitrate and

protocol

RS485

Set parameters for

RS485 serial
communication.
Bitrate, protocol

and address

Alarm config

Set pullup for the

external alarm pin

and polarity for

select signal

Language

Change the

language for local

control. Availability

varies with model

Interface config

MENU

Rack

Set parameters to
identify location of

the radio:

Rack number,

Row and column

5.4.3 Interface config group

SysOp access level. Refer to section 5.5.3 for details.

Figure 5.4-3, Interface config group, transmitter

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Measurements

Measure power
levels, voltages,

currents, lock

detect, etc.

Alarms

Display active

alarms. Identifies

modules and

parameter with

failure.

Bite system

MENU

System info

ID, FW and HW

release info.

Radio uptime.

MENU

5.4.4 Bite system group

SysOp and Technician access levels. Refer to section 5.5.4 for details.

5.4.5 System info group

All access levels.

Figure 5.4-4, Bite system group, transmitter

Figure 5.4-5, System info group, transmitter

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Menu path:
Radio control
►

Parameter

Range

Default

Details

Operation mode

Main | Norm

Norm

A main radio will enter into standby if an
alarm is detected by the internal BITE
system.
A norm radio will continue operation (if
possible) even if a failure is detected.
In a main / standby configuration, the main
radio is set to Main and the standby radio is
set to Norm. In this way the control can
automatically be transferred to the standby
radio by using the available alarm output and
select input on the radios.

Low power level

30 – 41 dBm
1 dB steps

41 dBm

Set the low power level of the transmitter in 1
dB steps. The low power level is the output
power of the transmitter when the transmitter
is set to low power, either by a command or
by an external input signal.
30 dBm corresponds to 1W output, 41 dBm
is 12W ouput.

Modulation

FM

FM

Select the modulation type / waveform to
use.
Availability depends on radio specifications.

Alarm

On | Off

Off

This setting force the radio into alarm state
(forced alarm) if set to On.
Used for simulations, or to force a radio to
signal an alarm in order to select a backup
(standby) radio.

Standby

On | Off

Off

This setting force the radio into standby state
(forced standby) if set to On.
Used to manually set a radio to standby.

Menu path:
TX config ►

Parameter

Range

Default

Details

FM

Output power

30 – 47 dBm
1 dB steps

47 dBm

Set the output power for FM operation.
Max. level depends on radio model and is:

 47 dBm for TA7650C

FM

Modulation

Up to ±5kHz
deviation

±5kHz

Set the deviation for FM operation.

5.5 Parameter details – transmitter

5.5.1 Radio control group

Table 5.5-1, Radio control group, transmitter

5.5.2 TX config group

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Menu path:
TX config ►

Parameter

Range

Default

Details

Audio

Input source

Auto | Line | Mic
| modgen | VoIP

Auto

The input source determines where the audio
is applied to the transmitter.

 Auto: Uses line input for when a

key signal is detected on one of
the remote connectors and mic
input if the key signal is detected
on the front panel connector.

 Line: Uses the 600 ohm line

interface as the audio source

 Mic: Uses the microphone input as

the audio source

 Modgen: Uses the internal

modgen as audio input source – se
also Modgen frequency

 VoIP: Uses the IP interface as the

audio source (availability depends
on radio specifications).

Audio

Mic sensitivity

-40 – 0 dBm
1 dB steps

-25 dBm

Set the gain (sensitivity) for the microphone
connected to the front panel connector.
Use this setting to increase or decrease the
gain if needed. Setting depends on
microphone used.

Audio

Line sensitivity

-40 – 0 dBm
1 dB steps

-17 dBm

Set the sensitivity of the 600 ohm line input.
This setting determines where the VOGAD
(automatic gain control) start to operate.
Thus if it is set to -17 dBm, levels above -17
dBm will be modulated with 85% (default
setting).
For levels below -17 dBm the modulation will
decrease linearly.

Audio

Line termination

OFF | 600 ohm

600 ohm

Set the termination of the input line to either
OFF or 600 ohm. Normally this is set to 600
ohm, but can be set to OFF on one of the
radios, if two transmitters are connected in
parallel. This is to maintain the 600 ohm
impedance on the lines.

Audio

Line mute level

OFF or

-40 to -10dBm
1 dB steps

OFF

Below this level, the line input will be muted.
Used where noisy lines are connected to the
transmitter to avoid unnecessary noise on
the produced RF signal during periods of
silence (Automatic transmissions; VOLMET,
ATIS)

Audio

Monitor output

Headset |
Monitor output

Monitor
output

Set where the monitor output signal and the
received audio (if a receiver is connected) is
routed.
Can be set to the headset connector, the 600
ohm monitor line output or both.
The monitor signal is the demodulated signal
detected on the output of the transmitter.

Audio

Monitor level

-80 – 10 dBm

-50 dBm

Set the relative output level of the monitor
signal.

Audio

VOGAD

Off, x-fast, fast,
norm, slow, x­slow

Norm

Set the attack and decrease time of the
automatic gain control (VOGAD).

 Off is used only for maintenance

purposes.

Audio

Modgen frequency

100 – 5000 Hz
1 Hz steps

1003 Hz

Set the frequency of the internal modulation
generator. Used in conjunction with the
Audio input source

Audio

Line=>Head gain

-10 to +20 dB

0 dB

Defines the scaling factor of the Rx Audio on
the headset output when the transmitter is
connected to a receiver.
The level is a relative value -10 to +20 dB

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-10

Menu path:
TX config ►

Parameter

Range

Default

Details

Keying

Source

Mic, line, txkey,
txgnd, inband

Mic, txkey

Determines what signal that will be used as
the source for keying the transmitter.
Any combinations can be set

 Mic: Local PTT input from a

microphone, where the PTT is
connected to pin 4 and 8(gnd) on
the Mic/headset connector.

 Line: Keying from a phantom

signal on the line input. Pin 3 and 6
on the REM connector.

 Txkey: The transmitter is keyed by

an external voltage on the
TXKEY_P and TXKEY_N input
pins. Signals located on Pin 7 and
8 on the | connector.

 Txgnd: The transmitter is keyed

by a signal on the TXKEY_G input
pin Signals are located on Pin 4
and 8 (gnd) on the REM
connector.

 Inband: The transmitter is keyed

using an inband tone (see also
inband frequency and inband
sensitivity)

Keying

Inband frequency

100 – 5000 Hz
1 Hz steps

5000

Set the frequency to be used for the inband
tone that will be used to key the transmitter.
By selected the tone frequency to use, the
transmitter will automatically calculate the
notch filter to use an insert this into the audio
path. Applicable to the line interface input
only.

Keying

Inband trig level

-40 to -10 dBm

-30

The level of the tone used to key the
transmitter on the 600ohm input line.
The value is given in dBm (absolute level
related to 600 ohm). Values above the limit
will key the transmitter.
See also Keying source and Inband
frequency.

Keying

TX Timeout

OFF | 15-300 s
1s steps

OFF

Set the timeout for the key signal. If the PTT
is pressed longer than this timeout, the
transmitter will automatically stop
transmitting. The transmitter will
automatically reset the timer when the key
signal is released.

Keying

RF delay

0 – 200 ms

0 (OFF)

This setting is useful when the transmitter is
used together with external equipment such
as T/R relays, power amplifier or other
equipment that includes RF switchover
relays.
Since the RF switching in the transmitter is
done electronically, the RF is produced in
less than 10ms after the PTT signal is
detected. It could be harmful for the external
relays if the RF is applied to them before
switchover has occurred.
In order to delay the RF carrier this
parameter should be used under such
circumstances. A reasonable setting should
be in the order of 40-50 ms.

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-11

Menu path:
TX config ►

Parameter

Range

Default

Details

Keying

Loop key bias

Ground, +12V,
Floating

Floating

Connects the centre pin of the line input
transformer to:

 Floating: The centre pin is not

connected. If loop keying is used,
an external voltage must be
applied to pin 3 (REM connector)
in order to key the transmitter

 Ground: The centre pin is

grounded. If loop keying is used,
an external voltage must be
applied to pin 3 (REM connector)
in order to key the transmitter.

 +12V: A 12V DC is supplied on pin

3(REM connector). The transmitter
can be keyed with a relay (or
equivalent) that create a DC path
on the line input pin, pin 3 and 6
(REM connector).

Calibrate

Ref oscillator

-127 – +128

0

This setting is used to fine adjust (calibrate)
the reference oscillator of the transmitter.
The full range is approximately 10 ppm. This
setting should be used with care, and only
when a calibrated frequency measuring
instrument is connected to the transmitter.

Menu path:
Interface
config ►

Parameter

Range

Default

Details

Access control

SysOp,
Technician,
Operator,
Restricted

SysOp

Set the user access level for local control.
This setting limits the availability of some
menus, depending on the access level. In
order to set the access level from the user
interface, a special hardware key must be
inserted into the microphone/headset
connector. Details of the key is available in
chapter Error! Reference source not

ound.

Set language

Depending on
model

English

Set the language to use on the user
interface. Availability of different languages
depends on specifications when ordering
the transmitter.

Alarm config

Alarm pin pull-up

Disabled |
Enabled

Enabled

The ALARM_OUT_P and ALARM_OUT_N
output pins on AUX1 is used to signal that
the radio has an alarm. This parameter
applies a pull-up voltage to ALARM_OUT_P
when there are no alarms present. When an
alarm is detected the relay contact close.

Alarm config

Select polarity

High to select|
Low to select

Low to
select

The SELECT_IN_P and SELECT_IN_N
input pins on AUX1 can be used to select /
deselect (Standby) the radio with an
external signal (e.g. alarm from a main
radio). This setting determines if the radio
should be operational on a low select input
signal or a high select input signal.

RS485

Bitrate

1200 – 115200

1200

Set the bit rate to use on the RS485 port

Table 5.5-2, TX config group, transmitter

5.5.3 Interface config group

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-12

Menu path:
Interface
config ►

Parameter

Range

Default

Details

RS485

Address

1 – 255

1

Set the address to use on the RS485. In a
remote system using the RS485
communication port, all units that are
interconnected need to have a unique
address in order to avoid collisions and
misinterpretation of data.

RS485

Protocol

Legacy |
standard

Legacy

The protocols are described in the data
manual.
Legacy uses a protocol where the 9. bit is
used for address recognition, this is the
protocol used on the previous radio models
(TA7450, RA7202) and is compatible with
the RACS II PC software and the RCU
remote control unit.
Standard is an eight bit protocol that uses
the multidrop capability of the RS485 bus.
For more information on protocols, refer to
the SW manual.

RS232

Bitrate

1200 – 115200

115200

Set the bit rate to use on the RS232
interface ports

LAN

Address

4 octets IP
address

192.168.2.1

IP interface address for the unit. Must be
unique on the network it connects to.

LAN

Netmask

4 octets IP
netmask

255.255.0.0

The netmask used on the IP interface.
Should correspond to the local network that
the radio is connected to.

LAN

Default gateway

4 octets IP
address

0.0.0.0

If set different from the default, the radio unit
will send IP traffic to the default gateway if
the address is unreachable on the local
network

LAN

SNMP port

1 – 65535

161

The input port used for SNMP commands
The default port is the global port for SNMP
commands

LAN

SNMP trap IP

4 octets IP
address

0.0.0.0

The IP address where SNMP traps are sent.
The address can be in the form of a unicast,
multicast or broadcast address.

LAN

SNMP trap port

1 – 65535

162

The output port where SNMP traps are sent.
The default value is the global port for
SNMP traps

LAN

SNMP trap int

0 – 60

5

The interval on which an “alive” trap
(operstate) are sent to the host, if the TrapIP
and TrapPort are set. The value is given in
seconds. 0=OFF

RACK

Number

0 – 100

0

Used to identify the location of the radio
from a remote application. Defines the rack
where the radio is located.

RACK

Row

0 – 20

0

Used to identify the location of the radio
from a remote application. Defines the row
number in the rack. The row number is
counted from the top to the bottom of the
rack.

RACK

Column

0 – 6 0 Used to identify the location of the radio
from a remote application. Defines the
column in the rack. The column number is
counted from the left in steps of one receiver

width or 14TE. There are 84 TE in a 19”

rack.

I.e. in a 19” frame width 6 receivers, the

receivers will have the column set to
1,2,3,4,5 or 6.

In a 19” frame width 3 transmitters, the

transmitters will have the column set to 1,3
or 5.

Table 5.5-3, Interface config group, transmitter

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-13

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-14

Menu path:
Interface
config ►

Parameter

Range

Default

Details

TX alarm

Depends on the
alarm status of the
radio unit

This option displays all active alarms in the
unit.
See section 6.1 for more info.

Measurements

Forward

30 – 47 dBm

Displays the forward power in dBm detected
at the output of the transmitter

Measurements

Reflected

0 – Forward
power

Displays the reflected power in dBm
detected on the output of the transmitter

Measurements

VSWR

1 : ∞ Displays the calculated VSWR from the
forward and reflected measurements

Measurements

Modulation

Up to ± 5kHz

Displays the measured modulation level on
the output of the transmitter [kHz]

Measurements

Current

Max 10 A when
keyed

Displays the total current consumption (28V)
of the transmitter [A]

Measurements

PA Temp

Max 85°C

Displays the temperature measured on the
PA module in the transmitter [°C]

Measurements

LO level

Min. 0 dBm

Displays the level measured at the output of
the local oscillator in dBm

Measurements

Line level

Input line level

Displays the input line level in dBm

Measurements

28 Volt

20.0 – 29.0 V

Displays the regulated 28V supply from the
power regulator board.
The 28V is used on the PA board.

Measurements

12 Volt

11.0 – 12.8 V

Displays the regulated 12V supply from the
power regulator board
The 12V is used on the main board

Measurements

6 Volt

5.0 – 7.0 V

Displays the regulated 6V on the modulator
board

Measurements

5 Volt

4.5 – 5.5 V

Displays the regulated 5V supply from the
power regulator board.
The 5V is used on several modules

Measurements

-5 Volt

-6.2 - -4.0 V

Displays the regulated -5V supply from the
power regulator board.
The -5V is used on the main board.

Measurements

3.3 Volt

2.9 – 3.6 V

Displays the regulated 3.3V supply from the
power regulator board.
The 3.3V is used on several modules

5.5.4 Bite system group

Table 5.5-4, Bite system group, transmitter

P/N: 84748 (G)

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Page 5-15

Display

Description

When the receiver is switched on, it will show the channel, the frequency
and the operation mode (FM).

When the DSC dedicated receiver is switched on, it will show the DSC
channel, the DSC frequency and the operation mode (DSC).

Press to navigate to the channel recall screen.
Select any channel (up to 100) that is previously stored in the radio by
rotating . Recall selected channel with
If no channel is stored, the display will show: CH: No channels

Press to navigate to the loudspeaker audio output screen.
This setting adjusts the audio level output in the integrated loudspeaker.
Rotate CW or CCW to adjust the audio level.

Press to navigate to the headset audio output screen.
This setting adjusts the audio level output in the integrated loudspeaker.
Rotate CW or CCW to adjust the audio level.

Press to navigate to the display intensity adjust screen.
This setting adjusts the intensity of the display and LED indicators.
Rotate CW or CCW to adjust the intensity.
Press to return to the default screen

Pressing from the main display will bring up the menu options that
are available for the current user level.
Press to disable / active the squelch.

Menus for user level: Restricted
For details regarding submenus, refer to chapter 5.4.

5.6 User menu – receiver (Restricted access level)

Main display window in restricted mode.

Table 5.6-1, User menu selections receiver - restriced access level

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-16

Display

Description

When the receiver is switched on, it will show the channel, the frequency
and the operation mode (FM).

When the DRC dedicated receiver is switched on, it will show the DSC
channel, the DSC frequency and the operation mode (DRC).

Press to navigate to the channel recall screen.
Select any channel (up to 100) that is previously stored in the radio by
rotating . Recall selected channel with
If no channel is stored, the display will show: CH: No channels

Press to navigate to the loudspeaker audio output screen.
This setting adjusts the audio level output in the integrated loudspeaker.
Rotate CW or CCW to adjust the audio level.

Press to navigate to the headset audio output screen.
This setting adjusts the audio level output in the integrated loudspeaker.
Rotate CW or CCW to adjust the audio level.

Press to navigate to the channel select screen.
Select channel number by rotating CW or CCW.
Confirm new frequency with or .

Confirm with or .
If the channel is already programmed, the channel may be cleared using

Press to navigate to the display intensity adjust screen.
This setting adjusts the intensity of the display and LED indicators.
Rotate CW or CCW to adjust the intensity.
Press to return to the default screen

Pressing from the main display will bring up the menu options
available for the current user level.
Press to disable / activate the squelch.

Menus for user level: Operator
For details regarding submenus, refer to chapter 5.4.

5.7 User menu – receiver (Default access level)

Main display window for user levels: Operator, Technician and SysOp.

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-17

Menus for user level: Technician
For details regarding submenus, refer to chapter 5.4.

Menus for user level: SysOp
For details regarding submenus, refer to chapter 5.4.

Submenu

Access level

Description

Radio control ►

SysOp, Technician

Access to operation mode, low power level, climax offset
parameters, modulation and standby settings.

RX config ►

SysOp

Access to configuration parameters for modulation, audio
settings, Squelch settings and internal calibration settings.

Interface config ►

SysOp

Access to configuration parameters for the ethernet
interface, RS232 port, RS485 port, various pin settings on
the hardware interface (remote connectors) and the user
access level.

Bite system ►

SysOp, Technician

Displays information about active alarms and gives the
user access to internal measurements.

System info ►

All

Displays information about the firmware and hardware
release, system up-time and radio identification

Table 5.7-1, User menu selections receiver - Operator, Technician and SysOp access levels

5.8 Setting, information and configuration menus – receiver

Under the menu selection from the user menu, various submenu groups are available depending on
the user level.
The submenus and details for them are shown in the tables below.

Table 5.8-1, Submenus available on the receiver

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-18

5.8.1 Radio control group

SysOp and Technician access levels. Refer to section 5.9.1 for details.

Figure 5.8-1, Radio control group, receiver

5.8.2 RX config group

SysOp access level. Refer to section 5.9.2 for details.

Figure 5.8-2, RX config group, receiver

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-19

Access control

Set the user

access level for

local operation

Rack

Set parameters to
identify location of

the radio:

Rack number, row

and column

RS232

Set parameters for

RS232 serial

communication.

Bitrate and

protocol

RS485

Set parameters for

RS485 serial

communication.

Bitrate, protocol

and address

Alarm config

Set pullup for the

external alarm pin

and polarity for

select signal

Language

Change the

language for local

control. Availability

varies with model

Interface config

MENU

LAN

Set parameters for

ethernet (IP)

communication. IP

address, ports to

use, Gateway, etc.

5.8.3 Interface config group

SysOp access level. Refer to section 5.9.3 for details.

Figure 5.8-3, Interface config group, receiver

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-20

Measurements

Measure power

levels, voltages,

currents, lock

detect, etc.

Alarms

Display active

alarms. Identifies

modules and

parameter with

failure.

Bite system

MENU

System info

ID, FW and HW

release info.

System uptime.

MENU

5.8.4 Bite system group

SysOp and Technician access levels. Refer to section 5.9.4 for details.

5.8.5 System info group

Available for all access levels

Figure 5.8-4, Bite system group, receiver

Figure 5.8-5, System info group, receiver

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-21

Menu path:
Radio control
►

Parameter

Range

Default

Details

Squelch level

-10 dBuV to +30
dBuV

0 dBuV

Squelch level
This squelch level is the level for the digital
noise compensated squelch.

Operation mode

Main | Norm

Norm

A main radio will enter into standby if an
alarm is detected by the internal BITE
system.
A norm radio will continue operation (if
possible) even if a failure is detected.
In a main / standby configuration, the main
radio is set to Main and the standby radio is
set to Norm. In this way the control can
automatically be transferred to the standby
radio by using the available alarm output and
select input on the radios.

Modulation

FM

FM

Select the modulation type / waveform to
use.
Availability depends on radio specifications.

Alarm

On | Off

Off

This setting force the radio into alarm state
(forced alarm) if set to On.
Used for simulations, or to force a radio to
signal an alarm in order to select a backup
(standby) radio.

Standby

On | Off

Off

This setting force the radio into standby state
(forced standby) if set to On.
Used to manually set a radio to standby.

5.9 Parameter details – receiver

5.9.1 Radio control group

Table 5.9-1, Radio control group, receiver

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-22

Menu path:
RX config ►

Parameter

Range

Default

Details

Audio

Output source

Speaker |
Headphone |
Lineout |
VoIP

Speaker,
Headphone,
Lineout

The output source determines where the
received audio is output.

 Line: Output audio on the 600

ohm line interface

 Speaker: Output audio on the

integrated speaker.

 Headphone: Output audio to a

headphone connected to the front
panel connector.

 VoIP: Output audio on the IP

interface (availability depends on
radio specifications).

Audio

Line output level

-40 – +10 dBm
1 dB steps

-10 dBm

The max. output level on the 600 ohm line
output.

Audio

RF AGC

Off, x-fast, fast,
norm, slow, x­slow

Norm

Set the attack and release times for the RF
AGC

 Off is used only for maintenance

purposes.

Audio

AF AGC

On | Off

Off

Set the automatic AF gain control on or off.
Setting AF AGC on will lead to constant
audio output when received signals have
varying modulation levels

Audio

Mute on transmit

On | Off

On

Set this to On if the receiver should be
muted while transmitting. Requires that the
Tx busy signal on the RX connector on the
transmitter is routed to the TX busy input on
the receiver REM connector.

Squelch

Override level

-10 dBuV to +30
dBuV

20 dBuV

The override level where the analogue

squelch will open even if it is a “noisy”

signal. This squelch level overrides the
noise compensated squelch. Setting this

level to a lower level than the “SQ level” will

disable the noise compensated squelch
completely.

Squelch

Inband config

Off, open,
closed, both

Off

Defines the behavior of the inband squelch
signal.

 Off: No inband tone is generated
 Open: An inband tone is

generated when the squelch is
open (receiving)

 Closed: An inband tone is

generated when the squelch is
closed (muted)

 Both: Different tones are

generated depending on the
status of the squelch.

Squelch

Inband freq open

100 – 5000 Hz
1 Hz steps

5000

Set the frequency to be used for the inband
tone that will be used to signal that the
squelch is open. Requires that open is
included in the Inband config setting. The
receiver will automatically notch the received
signal and insert a tone at the given
frequency.
Applicable to the line interface output only.

Squelch

Inband freq closed

100 – 5000 Hz
1 Hz steps

5000

Set the frequency to be used for the inband
tone that will be used to signal that the
squelch is closed. Requires that closed is
included in the Inband config setting. The
receiver will automatically insert a tone at
the given frequency.
Applicable to the line interface output only.

5.9.2 RX config group

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-23

Menu path:
RX config ►

Parameter

Range

Default

Details

Squelch

Inband level

-30 to -10

-24

The level of the inband tone relative to the
setting in the line level output level in dB,
Applicable to the line interface output only.

Squelch

SqOut output

Set the behavior of the SqOut output (AUX2,
p.1 and p.2).

Squelch

RxBusy output

Closed | Open |
Closed on busy|
Open on busy

Closed on
busy

Set the behavior of the RxBusy output
(REM, p.5).

Calibrate

Ref oscillator

-127 – +128

0

This setting is used to fine adjust (calibrate)
the reference oscillator of the receiver. The
full range is approximately 10 ppm. This
setting should be used with care, and only
when a calibrated frequency measuring
instrument is used to measure the frequency
of the receiver.
The exact frequency of the receiver can be
determined either by connecting a spectrum
analyzer to the antenna connector of the
receiver and measure the leakage of the LO
output (45 MHz above the operating
frequency) – or by using a radio test set to
measure the bandwidth of the receiver and
adjust until centre is on the operating
frequency.

Calibrate

RSSI reading

-10 to +10 dB

0 dB

In order to measure the RSSI level exactly,
there is a provision to calibrate the reading.
Normally the reading is within +/-2 dB
without calibration, but it can be useful if to
signals are being compared.

Factory preset

0, 1

0

Writing a “1” to this parameter will reset the

receiver and restore the settings that where
set before shipping from the factory. Use
with care – all settings that has been
changed will be reset!

Menu path:
Interface
config ►

Parameter

Range

Default

Details

Access control

SysOp,
Technician,
Operator,
Restricted

SysOp

Set the user access level for local control.
This setting limits the availability of some
menus, depending on the access level. In
order to set the access level from the user
interface, a special hardware key must be
inserted into the microphone/headset
connector. Details of the key is available in
chapter Error! Reference source not

ound..

Set language

Depending on
model

English

Set the language to use on the user
interface. Availability of different languages
depends on specifications when ordering
the receiver.

Alarm config

Alarm pin pullup

Disabled |
Enabled

Enabled

The ALARM_OUT_P and ALARM_OUT_N
output pins on AUX1 is used to signal that
the radio has an alarm. This parameter
applies a pullup voltage to ALARM_OUT_P
when there are no alarms present. When an
alarm is detected the relay contact close.

Table 5.9-2, RX config group, receiver

5.9.3 Interface config group

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-24

Menu path:
Interface
config ►

Parameter

Range

Default

Details

Alarm config

Select polarity

High to select|
Low to select

Low

The SELECT_IN_P and SELECT_IN_N
input pins on AUX1 can be used to select /
deselect (Standby) the radio with an
external signal (e.g. alarm from a main
radio). This setting determines if the radio
should be operational on a low select input
signal or a high select input signal.

RS485

Bitrate

1200 – 115200

1200

Set the bit rate to use on the RS485 port

RS485

Address

1 – 255

1

Set the address to use on the RS485. In a
remote system using the RS485
communication port, all units that are
interconnected need to have a unique
address in order to avoid collisions and
misinterpretation of data.

RS485

Protocol

Legacy |
standard

Legacy

The protocols are described in the data
manual.
Legacy uses a protocol where the 9. bit is
used for address recognition, this is the
protocol used on the previous radio models
(TA7450, RA7202) and is compatible with
the RACS II PC software and the RCU
remote control unit.
Standard is an eight bit protocol that uses
the multidrop capability of the RS485 bus.
For more information on protocols, refer to
the SW manual.

RS232

Bitrate

1200 – 115200

115200

Set the bit rate to use on the RS232
interface ports

LAN

Address

4 octets IP
address

192.168.2.1

IP interface address for the unit. Must be
unique on the network it connects to.

LAN

Netmask

4 octets IP
netmask

255.255.0.0

The netmask used on the IP interface.
Should correspond to the local network that
the radio is connected to.

LAN

Default gateway

4 octets IP
address

0.0.0.0

If set different from the default, the radio unit
will send IP traffic to the default gateway if
the address is unreachable on the local
network

LAN

SNMP port

1 – 65535

161

The input port used for SNMP commands
The default port is the global port for SNMP
commands

LAN

SNMP trap IP

4 octets IP
address

0.0.0.0

The IP address where SNMP traps are sent.
The address can be in the form of a unicast,
multicast or broadcast address.

LAN

SNMP trap port

1 – 65535

162

The output port where SNMP traps are sent.
The default value is the global port for
SNMP traps

LAN

SNMP trap interval

0 – 60

5

The interval on which an “alive” trap

(operstate) are sent to the host, if the TrapIP
and TrapPort are set. The value is given in
seconds. 0=OFF

LAN

VDL output IP

4 octets IP
address

0.0.0.0

The IP address that VDL packets received
will be sent to. Must be set in order to detect
VDLpackets.

LAN

VDL output port

1 – 65535

3006

The output port used for VDL traffic if the
VDL input source is set to IP

Rack

Number

0 – 100

0

Used to identify the location of the radio
from a remote application. Defines the rack
where the radio is located.

Rack

Row

0 – 20

0

Used to identify the location of the radio
from a remote application. Defines the row
number in the rack. The row number is
counted from the top to the bottom of the
rack.

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-25

Menu path:
Interface
config ►

Parameter

Range

Default

Details

Rack

Column

0 – 6 0 Used to identify the location of the radio
from a remote application. Defines the
column in the rack. The column number is
counted from the left in steps of one receiver
width or 14TE. There are 84 TE in a 19”
rack.

I.e. in a 19” frame width 6 receivers, the

receivers will have the column set to
1,2,3,4,5 or 6.

In a 19” frame width 3 transmitters, the

transmitters will have the column set to 1,3
or 5.

Table 5.9-3, Interface config group, receiver

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  Operating Instructions

Page 5-26

Menu path:
Interface
config ►

Parameter

Range

Default

Details

RX alarm

Depends on the
alarm status of the
radio unit

This menu item displays all active alarms in
the unit.
See Receiver error conditions for more
information

Measurements

RSSI

-10 - +110 dBuV

Displays the received signal level (RSSI) in
dbuV

Measurements

Line level

-40 - +10 dBm

Displays the level measured on the output of
the 600 ohm line interface

Measurements

AGC volt

0 – 5 V

Displays the internal AGC voltage

Measurements

Codec/Eth LD

Lock / Unlock

Displays the status of the VCO used for the
Codec and Ethernet chips.

Measurements

Temperature

Max 85°C

Displays the internal temperature measured
on the main board [°C]

Measurements

DC current

0.1 – 0.3 A

Displays the total current consumption [28V]
of the receiver [A]

Measurements

IF current

20 – 60 mA

Displays the current consumption in the IF
(Intermediate Frequency) circuit [mA]

Measurements

LNA current

20 – 60 mA

Displays the current consumption in the LNA
(Low noise amplifier) [mA]

Measurements

LO level

Min. 15 dBm

Displays the level measured at the output of
the local oscillator in dBm

Measurements

LO lock

Lock / Unlock

Displays the status of the local oscillator in
the receiver.

Measurements

12 Volt

11.0 – 12.8V

Displays the regulated 12V supply from the
power supply board
The 12V is used on the main board

Measurements

6 Volt

5.0 – 7.0V

Displays the regulated 6V on the
demodulator board

Measurements

5 Volt

4.5 – 5.5V

Displays the regulated 5V supply from the
power supply board.
The 5V is used on several modules

Measurements

3.3 Volt

2.9 – 3.6V

Displays the regulated 3.3V supply from the
power supply board.
The 3.3V is used on several modules

Measurements

AC

Present/Not

Present / Not present. Signals that AC is
present or not present at the input of the unit.

Measurements

VDL2-CO

0 – 100 %

Displays the channel occupancy (CO) when
in VDL 2 mode. The value is calculated
every second, or by the interval set in VDL2­CO Trap interval.

5.9.4 Bite system group

Table 5.9-4, Bite system group, receiver

P/N: 84748 (G)

Jotron AS| TR7750C: Operators Manual  ERROR CONDITIONS AND CORRECTIVE ACTIONS

Page 6-1

Display

Description

Press from the main display to bring up the available menus.

Use to navigate to the Bite system menu and select by pressing

Select TX alarm

The displays shows module(s) where the BITE system has detected failures.
To view more details about the failure, select module.

6 ERROR CONDITIONS AND CORRECTIVE ACTIONS

When the internal BITE (Built In Test Equipment) in the transmitter or the receiver units detects a
failure, the alarm indicator on the front panel of the unit will be lit. In addition the radio unit will
signal with an automatically generated SNMP trap message on the ethernet interface.
Details about the fault that caused the alarm are accessible for user access levels: SysOp and
Technician.
The error messages are available in two levels, first the module that has the failure will be identified,
next the user has the option to view in details what particular message that caused the alarm
condition.

In the following (LRU) refers to the Lowest Replaceable Unit – and is normally the first line
maintenance where the complete unit is replaced. (LRM) refers to the Lowest Replaceable Module
and is the module within the unit that can be replaced. The LRM level normally requires a well
equipped workshop with appropriate tools for testing and calibration.

6.1 Transmitter error conditions

Table 6.1-1, Alarm indication, transmitter navigation

P/N: 84748 (pre_F)

Jotron AS| TR7750C: Operators Manual  ERROR CONDITIONS AND CORRECTIVE ACTIONS

Page 6-2

28V
12V

5V

3.3V

-5V

One of the voltage

readings is out of

range

High

Temperature

Temperature

reading is above

+85°C

High Current

Current

consumption is

above 10A

High SWR

Caused by a SWR

reading higher

than 1:3

PA Module

TX alarm

Action:

Check antenna /

Antenna

connectors /

Antenna Cable

Action:

Replace -

TX unit (LRU)

PA module (LRM)

Probable cause:
Defective output

transistor

Action:

Replace -

TX unit (LRU)

PA module (LRM)

Probable cause:

Defective fan(s)

Action:

Replace -

TX unit (LRU)

PA module (LRM)

Probable cause:

Defective

component on

power regulator

board

Figure 6.1-1, Transmitter PA module, errors and corrective actions

P/N: 84748 (pre_F)

Jotron AS| TR7750C: Operators Manual  ERROR CONDITIONS AND CORRECTIVE ACTIONS

Page 6-3

6V

Failure on 6V

regualtor on mod

module

LO lock detect

Synthesizer is out

of lock

LO level

The LO level is
below 0dBm

Mod module

TX alarm

Action:

Replace -

TX unit (LRU)

Modulator module

(LRM)

Probable cause:

Defective

synthesizer circuits

/ VCO / TCXO

Action:

Replace -

TX unit (LRU)

Modulator module

(LRM)

Probable cause:

Defective

synthesizer circuits

/ VCO / TCXO

Action:

Replace -

TX unit (LRU)

Modulator module

(LRM)

Probable cause:

Defective 6V

regulator

modulator board

Figure 6.1-2, Transmitter Modulator module, errors and corrective actions

P/N: 84748 (pre_F)

Jotron AS| TR7750C: Operators Manual  ERROR CONDITIONS AND CORRECTIVE ACTIONS

Page 6-4

Front

Failure on the
communication
link to the front

panel

DSP

Failure on the DSP

chip on the main

board

Codec

SPI
RemExp
BiteADC

Failure on one or

more ICs on the

main board

Ethernet

Failure on the
ethernet controller
on the main board

Main Module

TX alarm

Action:

Replace-

TX unit (LRU)

Main module

(LRM)

Probable cause:

Failure on the

ethernet chip

Action:

Replace -

TX unit (LRU)

Main module

(LRM)

Probable cause:

Failure on the
specified chip

Action:

Replace -

TX unit (LRU)

Main module

(LRM)

Probable cause:

Failure on the DSP

chip.

Action:

Replace -

TX unit (LRU)

Check connections

to the front panel,

replace front panel

(LRM)

Probable cause:

Failure on the front

panel or

connectors betw.

front panel and

main board

Figure 6.1-3, Transmitter Main module, errors and corrective actions

P/N: 84748 (pre_F)

Jotron AS| TR7750C: Operators Manual  ERROR CONDITIONS AND CORRECTIVE ACTIONS

Page 6-5

Display

Description

Press from the main display to bring up the available menus.

Use to navigate to the Bite system menu and select by pressing

Select Alarms and press

The displays shows module(s) where the BITE system has detected failures.
To view more details about the failure, select module.

6.2 Receiver error conditions

Table 6.2-1, Alarm indication, receiver navigation

P/N: 84748 (pre_F)

Jotron AS| TR7750C: Operators Manual  ERROR CONDITIONS AND CORRECTIVE ACTIONS

Page 6-6

12V

5V

3.3V

One of the voltage

readings is out of

range

High Current

Current
consumption is
above 500 mA

High

Temperature

Temperature

reading is above

+85°C

Power module

RX alarm

Action:

Replace ­RX unit (LRU)
Power module

(LRM).

Probable cause:

Failure on one or

more components

on the power

module.

Action:

Replace -

RX unit (LRU)

Power module,

Main module or RF

module (LRM).

Cause: Excessive

current

consumption in

one or more

modules.

Action:

Replace -

RX unit (LRU)

Power module,

Main module or RF

module (LRM)

Cause: Excessive

current

consumption or

defective voltage

regualtor.

Figure 6.2-1, Receiver Power module, errors and corrective actions

P/N: 84748 (pre_F)

Jotron AS| TR7750C: Operators Manual  ERROR CONDITIONS AND CORRECTIVE ACTIONS

Page 6-7

LNA current

Unnormal current

consumption in the

LNA (Low Noise

Amplifier)

LO lock detect

Synthesizer is out

of lock

LO level

The LO level is

below 0dBm

RF module

RX alarm

Action:

Replace -

RX unit (LRU)

RF module (LRM)

Probable cause:

Defective

synthesizer circuits

/ VCO / TCXO

Action:

Replace -

RX unit (LRU)

RF module (LRM)

Probable cause:

Defective

synthesizer circuits

/ VCO / TCXO

Action:

Replace -

RX unit (LRU)

RF module (LRM)

Probable cause:

LNA transistor

broken because of

high RF input or

transient caused

by lightning.

IF current

Unnormal current

consumption in the

IF circuitry.

Action:

Replace -

RX unit (LRU)

RF module (LRM)

Probable cause:

Defective IF chip

on the RF board

Figure 6.2-2, Receiver RF module, errors and corrective actions

P/N: 84748 (pre_F)

Jotron AS| TR7750C: Operators Manual  ERROR CONDITIONS AND CORRECTIVE ACTIONS

Page 6-8

Front

Failure on the

communication

link to the front

panel

DSP

Failure on the DSP

chip on the main

board

Codec

SPI
RemExp
BiteADC

Failure on one or

more ICs on the

main board

Ethernet

Failure on the
ethernet controller
on the main board

Main Module

RX alarm

Action:

Replace-

RX unit (LRU)

Main module

(LRM)

Probable cause:

Failure on the

ethernet chip

Action:

Replace -

RX unit (LRU)

Main module

(LRM)

Probable cause:

Failure on the
specified chip

Action:

Replace -

RX unit (LRU)

Main module

(LRM)

Probable cause:

Failure on the DSP

chip.

Action:

Replace -

RX unit (LRU)

Check connections

to the front panel,

replace front panel

(LRM)

Probable cause:

Failure on the front

panel or

connectors betw.

front panel and

main board

Figure 6.2-3, Receiver Main module, errors and corrective actions

P/N: 84748 (pre_F)

Jotron AS| TR7750C: Operators Manual  LIST OF TABLES AND FIGURES

Page 7-1

7 LIST OF TABLES AND FIGURES

TABLE 1.1-1, RADIO MODELS ...................................................................................................................................... 1-1

TABLE 3.1-1, MIC/HEADSET CONNECTOR, TRANSMITTER, PIN OUT..................................................................................... 3-2

TABLE 3.2-1, LAN INTERFACE CONNECTOR, PIN OUT ....................................................................................................... 3-5

TABLE 3.2-2, AUX1 CONNECTOR, TRANSMITTER, PIN OUT ............................................................................................... 3-5

TABLE 3.2-3, AUX2 CONNECTOR, TRANSMITTER, PIN OUT ............................................................................................... 3-6

TABLE 3.2-4, REM CONNECTOR, TRANSMITTER, PIN OUT ................................................................................................. 3-6

TABLE 3.2-5, RX CONNECTOR, TRANSMITTER, PIN OUT..................................................................................................... 3-7

TABLE 3.3-1, HEADSET CONNECTOR, RECEIVER, PIN OUT .................................................................................................. 3-9

TABLE 3.4-1, LAN INTERFACE CONNECTOR, PIN OUT ..................................................................................................... 3-11

TABLE 3.4-2, AUX1 CONNECTOR, RECEIVER, PIN OUT.................................................................................................... 3-11

TABLE 3.4-3, AUX2 CONNECTOR, RECEIVER, PIN OUT.................................................................................................... 3-12

TABLE 3.4-4, REM CONNECTOR, RECEIVER, PIN OUT ..................................................................................................... 3-12

TABLE 4.1-1, INSTALLATION PROCEDURES ..................................................................................................................... 4-1

TABLE 4.6-1, TRANSCEIVER, TRANSMITTER – RECEIVER INTERCONNECTIONS ......................................................................... 4-3

TABLE 4.6-2, SETTINGS ASSOCIATED WITH THE TRANSMITTER - RECEIVER INTERCONNECTION ................................................... 4-5

TABLE 4.6-3, SETTINGS ASSOCIATED WITH MONITOR OUTPUT (TA – AUX1) .................................................................. 4-6

TABLE 4.6-4, SETTINGS ASSOCIATED WITH LINE_INPUT (TX-REM) ................................................................................. 4-8

TABLE 4.6-5, SETTINGS ASSOCIATED WITH LINE_OUTPUT (RX-REM) ............................................................................. 4-8

TABLE 4.6-6, KEY SOURCE SETTINGS .......................................................................................................................... 4-10

TABLE 4.6-7, SQUELCH OUTPUT CONFIGURATION ......................................................................................................... 4-12

TABLE 4.6-8, ALARM AND SELECT SETTINGS, TRANSMITTER AND RECEIVER ......................................................................... 4-13

TABLE 4.6-9, MISC. SETTINGS, TRANSMITTER. .............................................................................................................. 4-15

TABLE 4.7-1, TRANSCEIVER, LOCAL CONFIGURATION ..................................................................................................... 4-17

TABLE 4.7-2, TRANSCEIVER, REMOTE (2W) INTERFACE ................................................................................................. 4-19

TABLE 4.7-3, TRANSCEIVER, REMOTE (4W) INTERFACE ................................................................................................. 4-20

TABLE 4.7-4, MAIN/BACKUP CONFIGURATION, TRANSMITTERS ........................................................................................ 4-21

TABLE 4.7-5, MAIN/BACKUP CONFIGURATION, RECEIVERS .............................................................................................. 4-22

TABLE 5.2-1, USER MENU SELECTIONS TRANSMITTER - RESTRICED ACCESS LEVEL ................................................................... 5-2

TABLE 5.3-1, USER MENU SELECTIONS TRANSMITTER- OPERATOR, TECHNICIAN AND SYSOP ACCESS LEVELS ............................... 5-3

TABLE 5.4-1, SUBMENUS AVAILABLE ON THE TRANSMITTER .............................................................................................. 5-4

TABLE 5.5-1, RADIO CONTROL GROUP, TRANSMITTER ...................................................................................................... 5-8

TABLE 5.5-2, TX CONFIG GROUP, TRANSMITTER ........................................................................................................... 5-11

TABLE 5.5-3, INTERFACE CONFIG GROUP, TRANSMITTER ................................................................................................. 5-12

TABLE 5.5-4, BITE SYSTEM GROUP, TRANSMITTER ......................................................................................................... 5-14

TABLE 5.6-1, USER MENU SELECTIONS RECEIVER - RESTRICED ACCESS LEVEL ....................................................................... 5-15

TABLE 5.7-1, USER MENU SELECTIONS RECEIVER - OPERATOR, TECHNICIAN AND SYSOP ACCESS LEVELS ................................... 5-17

TABLE 5.8-1, SUBMENUS AVAILABLE ON THE RECEIVER .................................................................................................. 5-17

TABLE 5.9-1, RADIO CONTROL GROUP, RECEIVER .......................................................................................................... 5-21

TABLE 5.9-2, RX CONFIG GROUP, RECEIVER ................................................................................................................. 5-23

TABLE 5.9-3, INTERFACE CONFIG GROUP, RECEIVER ....................................................................................................... 5-25

TABLE 5.9-4, BITE SYSTEM GROUP, RECEIVER ............................................................................................................... 5-26

TABLE 6.1-1, ALARM INDICATION, TRANSMITTER NAVIGATION .......................................................................................... 6-1

TABLE 6.2-1, ALARM INDICATION, RECEIVER NAVIGATION ................................................................................................ 6-5

FIGURE 3.1-1, FRONT VIEW, TRANSMITTER UNIT, TA-7650C/25C/10C ............................................................................ 3-1

FIGURE 3.2-1, REAR VIEW, TRANSMITTER UNIT, TA-7650C/25C/10C. ............................................................................. 3-4

FIGURE 3.2-2, TRANSMITTER DC INPUT CONNECTOR, REAR VIEW ...................................................................................... 3-4

FIGURE 3.3-1, FRONT VIEW, RECEIVER UNIT, RA-7203C ................................................................................................ 3-8

FIGURE 3.4-1, REAR VIEW, RECEIVER UNIT, RA-7203C. ................................................................................................ 3-10

P/N: 84748 (pre_F)

Jotron AS| TR7750C: Operators Manual  LIST OF TABLES AND FIGURES

Page 7-2

FIGURE 3.4-2, RECEIVER DC INPUT CONNECTOR, REAR VIEW .......................................................................................... 3-10

FIGURE 3.5-1, PSU-7002, FRONT VIEW ..................................................................................................................... 3-13

FIGURE 3.6-1, POWER SUPPLY UNIT - REAR VIEW .......................................................................................................... 3-14

FIGURE 3.6-2, DC INPUT CONNECTOR, PSU ................................................................................................................ 3-14

FIGURE 3.6-3, DC OUTPUT, PSU............................................................................................................................... 3-14

FIGURE 3.6-4, AC INPUT CONNECTOR, PSU ................................................................................................................ 3-15

FIGURE 4.3-1, EXAMPLES OF VARIOUS CONFIGURATIONS .................................................................................................. 4-2

FIGURE 4.6-1, AUDIO INTERFACES ON THE TRANSMITTER AND RECEIVER UNITS ..................................................................... 4-6

FIGURE 4.6-2, KEY SIGNALS ON THE TRANSMITTER UNIT ................................................................................................... 4-9

FIGURE 4.6-3, SQUELCH AND AGC SIGNALS RECEIVER UNIT ............................................................................................ 4-11

FIGURE 4.6-4, ALARM AND SELECT SIGNALS, TRANSMITTER ............................................................................................. 4-12

FIGURE 4.6-5, MISC SIGNALS, TRANSMITTER ................................................................................................................ 4-14

FIGURE 4.7-1, TRANSCEIVER, LOCAL CONFIGURATION, INTERFACING ................................................................................ 4-15

FIGURE 4.7-2, TRANSCEIVER, REMOTE CONFIGURATION WITH 2 WIRE AUDIO INTERFACE ...................................................... 4-18

FIGURE 4.7-3, TRANSCEIVER, REMOTE CONFIGURATION WITH 4 WIRE AUDIO INTERFACE ...................................................... 4-19

FIGURE 4.7-4, MAIN / BACKUP TRANSMITTER.............................................................................................................. 4-21

FIGURE 4.7-5, MAIN / BACKUP RECEIVER .................................................................................................................... 4-22

FIGURE 5.4-1, RADIO CONTROL GROUP, TRANSMITTER .................................................................................................... 5-5

FIGURE 5.4-2, TX CONFIG GROUP, TRANSMITTER ............................................................................................................ 5-5

FIGURE 5.4-3, INTERFACE CONFIG GROUP, TRANSMITTER ................................................................................................. 5-6

FIGURE 5.4-4, BITE SYSTEM GROUP, TRANSMITTER ......................................................................................................... 5-7

FIGURE 5.4-5, SYSTEM INFO GROUP, TRANSMITTER ......................................................................................................... 5-7

FIGURE 5.8-1, RADIO CONTROL GROUP, RECEIVER ........................................................................................................ 5-18

FIGURE 5.8-2, RX CONFIG GROUP, RECEIVER ............................................................................................................... 5-18

FIGURE 5.8-3, INTERFACE CONFIG GROUP, RECEIVER ..................................................................................................... 5-19

FIGURE 5.8-4, BITE SYSTEM GROUP, RECEIVER ............................................................................................................. 5-20

FIGURE 5.8-5, SYSTEM INFO GROUP, RECEIVER ............................................................................................................. 5-20

FIGURE 6.1-1, TRANSMITTER PA MODULE, ERRORS AND CORRECTIVE ACTIONS ..................................................................... 6-2

FIGURE 6.1-2, TRANSMITTER MODULATOR MODULE, ERRORS AND CORRECTIVE ACTIONS ....................................................... 6-3

FIGURE 6.1-3, TRANSMITTER MAIN MODULE, ERRORS AND CORRECTIVE ACTIONS ................................................................. 6-4

FIGURE 6.2-1, RECEIVER POWER MODULE, ERRORS AND CORRECTIVE ACTIONS ..................................................................... 6-6

FIGURE 6.2-2, RECEIVER RF MODULE, ERRORS AND CORRECTIVE ACTIONS ........................................................................... 6-7

FIGURE 6.2-3, RECEIVER MAIN MODULE, ERRORS AND CORRECTIVE ACTIONS ....................................................................... 6-8

P/N: 84748 (pre_F)

Jotron AS| TR7750C: Operators Manual  LIST OF MARITIME CHANNELS AND FREQUENCIES

Page 7-1

Channel

Designators

BASE RX

MHz

BASE TX

MHz

0

156.000

156.000

60

156.025

160.625

1

156.050

160.650

61

156.075

160.675

2

156.100

160.700

62

156.125

160.725

3

156.150

160.750

63

156.175

160.775

4

156.200

160.800

64

156.225

160.825

5

156.250

160.850

65

156.275

160.875

6

156.300

156.300

66

156.325

160.925

7

156.350

160.950

67

156.375

156.375

8

156.400

156.400

68

156.425

156.425

9

156.450

156.450

69

156.475

156.475

10

156.500

156.500

DSC 70

156.525

156.525

11

156.550

156.550

71

156.575

156.575

12

156.600

156.600

72

156.625

156.625

13

156.650

156.650

73

156.675

156.675

14

156.700

156.700

Channel

Designators

BASE RX

MHz

BASE TX

MHz

74

156.725

156.725

15

156.750

156.750

75

-

156.775

16

156.800

156.800

76

-

156.825

17

156.850

156.850

77

156.875

156.875

18

156.900

161.500

78

156.925

161.525

19

156.950

161.550

79

156.975

161.575

20

157.000

161.600

80

157.025

161.625

21

157.050

161.650

81

157.075

161.675

22

157.100

161.700

82

157.125

161.725

23

157.150

161.750

83

157.175

161.775

24

157.200

161.800

84

157.225

161.825

25

157.250

161.850

85

157.275

161.875

26

157.300

161.900

86

157.325

161.925

27

157.350

161.950

87

157.375

157.375

28

157.400

162.000

88

157.425

157.425

Appendix A. LIST OF MARITIME CHANNELS AND FREQUENCIES

P/N: 84748 (pre_F)