Where are your divers?

A rugged wearable transmitter that goes in the water with every diver. It broadcasts its position by radio whenever it is at the surface — no phone, no signal plan, nothing for the diver to operate.

How it's worn

• Clips to a D-ring, or straps on with velcro. Either one works on its own, so it fits whatever the diver is already wearing — and nothing on their gear has to be modified.
• Either way it rides high on the shoulder strap, so the antenna clears the water when the diver surfaces.

On the water

• SOS pull pin. One pull sets off an audible and visual alarm on the boat that flags exactly which diver pulled it and gives the crew distance and bearing to them — a diver doesn't need to be seen or heard to be heard from.
• Flashing white LED. Chop hides a diver. So does glare, and the last hour of light. A flashing white light cuts through all three — and the crew can switch it on from the boat when they need to find someone.
• A display you can read on deck. The eMarker shows its own status on the unit — a battery indicator, a check mark when all systems are good and the diver is aboard and ready to dive, an X when something isn't right, low battery included. Crew can confirm a unit by looking at it, without going to the tablet.
• One button, opposite the SOS pin. A long press powers the eMarker on and off — deliberate enough that it won't happen against a tank, a strap, or a gear bag.
• Double-press to check a diver back on. As each diver comes aboard, the crew double-presses that eMarker — it sends the back-on-board alert and the diver's status flips from Not Visible to Aboard. One press per diver, and the count keeps itself.
• Position reporting is automatic. Once the unit is on, it reports whenever its antenna is clear of the water. A diver never has to operate it to be tracked — the button is for checking in, not for being found.
• A surfacing is a notification. The moment a diver's eMarker comes back up and reports, the crew sees it on the tablet — including the ones who surface well off the stern, out of sight.
• Two-week battery life, shown on the unit's display and in the app.
• Two weeks of use, about an hour to refill. The eMarkers sit together in a multi-unit dock and charge through external contacts — the whole fleet at once, flat to full in roughly an hour, while the boat is tied up.
• The cases stay sealed. Charging runs through external contacts, so there's no port to open, no cap to lose, and nothing for salt water to work its way into.
• 5 nautical miles is typical between the eMarker and the base station, and further where the boat's antenna is mounted higher.

Setup

• Every eMarker carries its own QR code. Scan it with the tablet or phone and that unit is connected to the base station it's working with — adding a diver to the dive takes a scan.

The receiver that lives on the boat. It listens for every eMarker in the water and feeds their positions to the tablet — over its own radio link, not over the internet.

Installation

• Available as a hand-held mount or hard-wired to the vessel — fits charter boats, six-packs, and RIBs alike.
• The antennas mount to the highest points on the boat.

What it does

• No internet. No cell service. The boat and the eMarkers talk directly, which means the system works on an offshore wreck exactly as it does at the dock.
• 5 nautical miles is typical between the base station and the eMarkers in the water. Range follows antenna height, the same way VHF does — the higher the mount, the further it reaches.
• Distance you can act on. Every reporting eMarker is placed with accurate distance and bearing from the boat, which is what turns the geofence and too-far alerts in the app into something the helm can steer by.
• Continuous monitoring of every unit's status while the dive is running.

This is the screen the crew works from. It runs on any Android or iOS tablet or phone, and it's where a surfaced diver stops being a speck in the chop and becomes a distance and a bearing.

When someone pulls the pin

• Every screen alarms. Audible and visual — the crew doesn't have to be watching the tablet to know something has happened.
• Their row lights up. The alarm highlights that diver's row in the list — by name if the crew entered one, by eMarker otherwise. Either way the crew knows someone needs help.
• It gives you a direction. Distance and bearing from the boat to that eMarker, so the response starts with a course to steer instead of a search.
• Acknowledge to clear it, so the crew can confirm the alarm has been seen and get on with the response.

Who needs you first

• Every eMarker sits in one of six states — Aboard, Visible, Not Visible, Too Far, Overdue, SOS — and the list is ordered by priority, so whoever needs attention rises to the top.
• Each row carries what the crew needs: eMarker ID, status, distance and bearing from the boat, battery level, and location history.
• Names and notes. Under User, the crew puts a name against each eMarker and keeps notes on that customer — so the list reads as people, not unit numbers.

Where they are

• The eMarker map is boat-centered — you are always at the middle, with every eMarker placed around you by distance and bearing, so pointing the boat is a glance rather than a guess. What the crew chooses is which way the map is turned: North Up or Heads Up — north fixed at the top, or the boat's heading up — the same choice their chartplotter gives them.
• Works in landscape or portrait, with zoom.
• Geofencing: set the boundary for the site and get alerted when a diver drifts past it.

What the crew can send

• LED on or off, from the tablet. The crew can switch a unit's light on or off as conditions call for it. The command goes out to that eMarker the next time it is in communication with the base station.
• Dive timers. Before the dive, the crew sets the time limit once and sends it to every eMarker at once — not unit by unit. Each countdown runs from the start of that diver's own dive, and anyone who goes beyond the limit is Overdue — the eMarker sounds an audible alert until that diver surfaces and communicates with the base station. An overdue diver hears about it in the water, not just the crew on deck.

Setup and access

• Multi-device login — captain and divemaster can both be watching, on separate screens.
• Scan to add a unit. The tablet or phone reads the QR code on an eMarker to connect it to the base station — no installation crew, no account to provision.
• Runs entirely without internet or cell service.