Promising to revolutionise how sailors communicate on board, the Vesper Cortex integrates VHF radio, Class B AIS, remote vessel monitoring and more

Tested: Vesper Cortex VHF radio, AIS and remote monitoring

The modern sailor has an array of navigation systems at their fingertips providing information and certainty unimaginable to previous generations.

As radio, GPS, radar and AIS have proliferated, so to have the electronic gizmos at the chart table and on deck.

Getting them to talk to each other can still be a challenge, even in the days of NMEA 2000.

Problems can arise when you try to integrate different transmitting devices, such as DSC radio, AIS, WiFi and cellular gateways, and all the radio frequency processing that goes with that, which is where the Vesper Cortex comes in.

Vesper Cortex VHF, AIS and Monitoring

Vesper Cortex VHF, AIS and Monitoring is easy to install

A neat black box, hidden away, and an intuitive user interface for the smartphone world, integrates all of those functions so that they work seamlessly together.

So what does it do?

Cortex is a DSC handheld VHF radio with up to ten tethered or wireless handsets.

It is a Class B+ SOTDMA AIS transceiver sharing the VHF antenna to avoid splitter issues, although it includes a splitter for a standalone VHF radio to run through the same antenna.

The smartAIS also calculates collision risks and necessary avoiding action. It is an anchor watch and MOB alarm system.

It is a remote monitoring and control system when you’re off the boat. It is a wifi gateway between your smart devices and boat network.

It is a verbal alarm system that tells you what an alarm is for without needing to look at the screen.

Because the system is built around its software, rather than separate hardware for each function, it can do all of these things at once, and has the capacity to have new functionality added over time, avoiding the need to replace it, hopefully for some time.

Intercom between the handsets, multi-channel VHF scanning, and radio transmission rewind to listen back to conversations you missed are all in the pipeline. 

Installation of the Vesper Cortex

Installation is pretty straightforward, and you can install it alongside your existing setup, or instead of, and get rid of a number of bulky boxes.

It requires power, a network cable, antenna cable and a GPS cable, and each handset needs a power supply (all data is wireless), either to the wired tether, or to the charging cradle for the wireless handset, though this doesn’t need to be near where you are going to use it.

It has its own wifi antenna as well as built-in sensors including battery voltage, barometer, 9-axis motion and heading sensor, five ports for NMEA 0183 or NMEA 2000 inputs and two outputs so you can monitor any information on your network and add a speaker.

In normal listening mode with AIS on, it uses just 0.8A (12V). Transmitting on VHF low power that goes up to 0.9A and on high power 3.4A. 

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Audio is provided by a 10W, 85dB speaker in each handset, and both the hub and the handsets are IPX7 waterproof (submersion for 30 minutes).

The very high resolution, sunlight visible touch screens are made with toughened Gorilla glass, and can be used when wet or with gloved hands, though all controls are replicated with physical buttons (menu, back, VHF, Ch 16, MOB and Call) and paddlewheel.

The handsets have rubber edges and back for antislip and protection.

The microphone is central on the front, with a push-to-talk button on the left side and volume control and power button on the right, and a DSC distress button under a hinged flap on the back, so it feels like a standard VHF handset to use. 

Operating the system

For a system that does so much, operation is surprisingly intuitive and simple. There are seven main screens, accessible from the main menu giving: VHF radio, Vessel directory, AIS plotter, Instruments, Collision avoidance, Anchor watch and MOB.

Every page has a status bar across the top showing VHF channel and power, and the status of battery, GPS and wifi.

The VHF radio page shows your call sign and MMSI number, transmission power, channel and its intended purpose – selected by swiping the screen or rotating the paddlewheel, saved favourite channels and dual watch.

Squelch is set automatically to your preferred sensitivity (though exact control would be nice and volume can be set for the hub, or for individual handsets. At the bottom of the screen any watched vessels or collision risks are displayed.

The AIS vessel directory page displays priority/collision risk vessels, then saved favourites, then other alphabetically, with the option to call, find on the plotter screen, or avoid.

The plotter screen doesn’t have any cartography, but has a clear range display, with head up or north up options, zoomable from 0.5 miles to 60 miles.

Collision risks or saved vessels are highlighted and you can filter out vessels such as those that aren’t moving.

The icons show whether it is a ship, power or sail and how fast it is going. You can see all of the same data displayed on your chartplotter screen.

Tap one to bring up vessel details, including current range and bearing, CPA and TCPA, and call it on DSC, or to view it in Collision avoidance, where you can see the impact of any course adjustments on your CPA before you make them. 

When you come to anchor, hit the anchor down button to record it’s precise location, and then set your desired guard zone.

The page displays depth, calculates the scope chain you have laid, and other vessels on AIS. You can alter exact anchor location and swinging circle parameters.

It will voice an alert if you drag, the wind changes, or you hit a water depth parameter.

If you have the Vortex Cortex Onboard app, you will get a phone notification for any alarms set, both for anchoring and any on board systems selected, with a full view of the same information and display as if you were on board. 

Verdict on the Vesper Cortex

What this does is bring almost every electronic function other than navigation into one place, designed to function seamlessly together.

Having installed the unit, connected the handsets and entered my boat’s details, there was no setup – it all just worked.

Using the Vesper Cortex as an AIS to find, contact and avoid other vessels, and as a plain VHF radio, all while standing at the helm with a handheld device, was so intuitive that I quickly forgot how revolutionary this actually is.

There are other DSC radios with integrated Class B AIS just coming on to the market as well, but the fact that it does so much more – not least anchor watch and remote monitoring – makes this a genuinely game-changing piece of equipment. 

Quality and functionality were all top notch.

It felt solid and rugged, worked well when wet and not at all vulnerable.

On small boats, the tethered handset supplied would be sufficient, with a socket at the chart table or on deck allowing you to use it in both places.

On larger vessels, the ability to keep the handset on you at the helm, on deck or by your bunk is invaluable.

The thought of losing one overboard, especially if it’s your only handset, doesn’t bear thinking about, so clipping on a lanyard and float would be the first thing I would do.

The only slight gripes I had was that the screen wasn’t quite as bright in direct sunlight as my B&G Triton 2 instrument display, though it was still perfectly legible

Unsurprisingly, it comes with an eye-watering price tag, at least compared to other radios, though this quickly evens out if you also add in the cost of AIS, antennas, splitters and remote monitoring systems.

This is more likely, therefore, to be installed on new boats or those having a complete electronics upgrade so your setup can be designed around it.

While there are some shortcomings to the system – intercom, channel scanning and transmission rewind aren’t yet available – the reassuring thing about this system is that it is designed for functions to be added via free software upgrades as functions are imagined and added, making it a pretty future-proof investment.

Price of Vesper Cortex

V1 – Cortex Hub and tethered handset: £1,929.95

H1P – Portable handset: £649.95

M1 – Cortex Hub only: £1399.95

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