A Helicopter Is Inbound: The Story of the Jotron TR-910
Forget the specification sheet for a moment. To understand the Jotron TR-910, it is more useful to follow the people who might actually need it — offshore, in a vehicle, at a control position, or when the normal communications position is no longer available.
A helicopter is twenty minutes out.
Out on an offshore installation, that message changes the rhythm of the working day.
People prepare for the aircraft’s arrival. The helideck operation has its procedures, the aircraft has its crew, and somewhere in the communications chain an operator needs the appropriate means of communicating on the aviation band.
This is where an important distinction needs to be made.
The operator reaches for the microphone connected to a Jotron TR-910 Offshore Radio.
At that particular moment, the person using it probably isn’t interested in how many versions of the TR-910 exist.
The requirement is much simpler.
The communications equipment needs to be available.
On the offshore installation
The radio at the operating position
Jotron supplies the Offshore version with a standard DIN flange for console mounting and states that custom-made flanges are available on request.
Jotron lists a handheld microphone, connection cables and an external AC/DC adaptor with this configuration.
It is a practical example of the TR-910 being configured around the place in which somebody actually needs to use it.
View TR-910 Offshore Radio · 103400OF →What if the normal operating position isn’t available?
The need for communications hasn’t disappeared simply because the normal position cannot be used.
Now the equipment has a different problem to solve.
The radio has to move with the operator.
Take the communications position with you
Jotron’s Man Portable version is based on the Last Resort Radio and places the radio, antenna and bracket into a carrying bag.
Jotron describes two pockets in that bag: one for a charger and cable and another for the microphone.
Jotron specifically identifies the portable arrangement for last-resort use if a tower is unavailable or in remote areas without the infrastructure of common airports.
Those test conditions are important. “Eight hours” on its own would tell only part of the story.
And then the AC supply disappears.
The communications requirement is still there.
What has changed this time is the power situation.
Now the name starts to make sense
Jotron describes the Last Resort version as similar to its Desktop Radio but equipped with a lithium-ion battery pack capable of supplying DC power to the radio if AC power fails.
Battery status can be monitored on the battery pack or on the TR-910 display.
The job hasn’t changed.
The availability of the normal power source has.
The next operator isn’t sitting behind a desk.
Across an airport, a utility vehicle is moving around the operational area.
There is no control-room desk in front of the operator and no equipment rack beside them.
There is, however, a vehicle electrical supply and a requirement for airband communications.
The workplace now has wheels
Jotron states that any vehicle with a 12 or 24 VDC supply can accommodate the TR-910 Vehicle Radio.
Jotron specifically identifies airport utility vehicles such as Follow-Me cars and passenger buses as applications.
The Vehicle package includes a microphone, interconnection cables, external loudspeaker and vehicle antenna.
The same basic communications problem has followed us into a completely different workplace.
Sometimes the simplest answer is a radio on a desk.
No vehicle. No carrying bag. Just the operating position.
Jotron states that its Desktop version can be used as the main radio in low-volume tower operations.
The radio is supplied with an external AC/DC adaptor covering 100–240 VAC.
Jotron lists a microphone, desktop mounting bracket, antenna cable connector and external AC/DC adaptor with the configuration.
View TR-910 Desktop Radio · 103400DE →What if the operator and the radio don’t need to be in the same place?
Walk into a larger control environment and the equipment arrangement can change again.
The transceiver does not necessarily need to occupy the operator’s desk.
The radio moves behind the scenes
Jotron offers the TR-910 as a subrack version for installation in existing 19-inch equipment racks or control-room consoles.
Jotron identifies the arrangement for installations where the radio is to be controlled using its RRC-7700 Radio Remote Control system.
We have now moved from simply having a radio beside an operator towards a larger communications architecture.
The helicopter is getting closer.
The transmitted RF energy has to leave the radio, pass through the feeder and its connections and reach the antenna.
Some of that power can be lost on the journey.
Here’s where 1 dB becomes interesting.
Jotron’s TR-910 technical documentation gives a feeder-loss example based on a 10 W transmitter.
8.5 W reaches the antenna.
7 W reaches the antenna.
Suddenly cable loss isn’t just a figure buried in an RF specification.
It is transmitter power that never reaches the antenna.
That is why cable type, length, connector installation, antenna selection and antenna location deserve to be considered as part of the communications system.
But what was actually said?
For some operations, communications have another requirement: recording.
Jotron states that the TR-910 Offshore Radio can integrate with its Ricochet SmartOil recorder system.
Jotron describes SmartOil as a recording solution developed for small onshore and offshore ATC operations and communications involving helicopters, offshore platforms and vessels.
So in an integrated installation, the communication does not necessarily disappear when the operator releases the push-to-talk button.
It can form part of the recorded operational history.
The radio isn’t alone anymore.
Once the radio is connected to networks, remote control, monitoring and recording systems, who — and what — is allowed to communicate with it?
This is why a modern radio specification can contain terminology that once sounded more like an IT department than a radio room.
Jotron publishes TR-910 capabilities including ED-137 VoIP, SNMPv3, VCS integration, recorder output and remote control and monitoring.
Jotron’s current TR-910 material also describes security measures including:
- SNMPv3 secure monitoring
- Role-based access control
- Authentication
- Cryptographically signed software updates
- Encrypted communications and storage protection
- Firewall functionality
- Audit trails
- Alarms and event logs
- Backup functionality
The RF signal still leaves through an antenna.
But the modern radio has another doorway: the network.
Then the gas alarm operates.
Buried deeper in the TR-910 technical documentation is a useful example of how the radio’s configurable I/O can be applied offshore.
It is a relatively small technical detail, but an interesting one.
The word offshore isn’t simply being added to the name because the radio happens to be pictured near a helideck.
Jotron has an actual Offshore configuration and documents functionality relevant to that environment.
What if the radio in front of you says TR-810?
Some engineers encountering the TR-910 may be arriving at it through an older Jotron installation.
Jotron issued an end-of-life notice for the TR-810 VHF/AM Transceiver and identified the TR-910 as its replacement.
Jotron’s replacement information mapped older TR-810 configurations to corresponding TR-910 configurations including Desktop, Last Resort, Manpack, Offshore, Subrack and Vehicle versions.
What about the Jotron TR30 AIR?
F&C Marine also supplies the Jotron TR30 AIR.
It is important not to merge the two products simply because both deal with aeronautical AM communications.
The TR-910 is Jotron’s multipurpose VHF AM airband platform offered in several fixed, portable, vehicle, offshore and rack configurations.
The TR30 AIR is a separate handheld emergency AM aeronautical radio.
They perform different roles and should be selected according to the actual requirement.
Two TR-910 configurations from the story
We’ve followed the TR-910 through several very different situations. Two of those configurations now have dedicated F&C Marine product pages.
Jotron TR-910 Offshore Radio
The dedicated Offshore configuration from the beginning of our story, supplied for fixed console-mounted airband communications applications.
View Offshore Radio → Jotron TR-910 Desktop Radio
The Desktop configuration from our operating-position scene, which Jotron states can be used as the main radio in low-volume tower operations.
View Desktop Radio →The correct TR-910 configuration depends on the operational, installation, power, interface and RF requirements of the particular application.
The helicopter is now approaching the helideck.
We started with an operator and an inbound aircraft.
Since then, we’ve taken the communications requirement away from the normal operating position and put the radio into a carrying bag.
We’ve removed the AC supply and seen why Jotron offers a battery-backed Last Resort configuration.
We’ve put the operator inside a Follow-Me vehicle.
We’ve put a radio on a desk and another out of sight in a 19-inch rack.
We’ve followed RF power along the feeder towards the antenna.
We’ve followed communications into a recording system and followed the radio itself onto an IP network.
And now we’re back offshore.
That’s where the word multipurpose starts to mean something.
The interesting thing about the TR-910 isn’t that one radio can be supplied with several different accessories.
It’s that Jotron has configured the same VHF AM airband platform around several very different situations in which people actually need to communicate.
Different places. Different operating conditions. Different configurations.
The common requirement is communication.
TR-910 Offshore · 103400OF TR-910 Desktop · 103400DE Discuss an Airband Communications Requirement Explore the F&C Marine Knowledge BaseTechnical sources & accuracy note
This article has been prepared from Jotron TR-910 manufacturer documentation and published product information. Technical requirements, options and configurations can change. Current manufacturer documentation applicable to the particular equipment should always be checked before specification, installation or maintenance.
Jotron — TR-910 Offshore Radio · Jotron — TR-910 Desktop Radio · Jotron — VHF AM Mobile Radio Range · Jotron — TR-910 Last Resort · Jotron — TR-910 Man Portable · Jotron — TR-910 Subrack