Owner’s Manual

Everything these do,
they do through one
button and one light.

This explains both — plus the two automatic behaviours that surprise almost everyone who owns a set.

Read this first

Your tracker turns itself off on purpose

If a tracker loses contact with the receiver for five minutes, it powers itself off completely — no light, no response, nothing when you plug it into a computer. That is deliberate battery saving, not a fault. It happens even while plugged in.

It does the same after fifteen minutes of sitting perfectly still. Press the button to wake it.

Three quick presses will unpair it

The button counts rapid presses, and three in a row clears the pairing. If a tracker suddenly stops connecting after you were fiddling with the button, that is almost certainly why — and it is a two-minute fix, not a broken tracker. See Pairing.

Turning them on and off

On

Press the button once. The light blinks twice quickly to confirm it is awake. A press shorter than a heartbeat sends it straight back to sleep, so make it deliberate.

Off

Press the button once while the tracker is running and unplugged. The light blinks three times and it shuts down.

It will not power off while charging or docked. That is by design — unplug it first.

What each press count does

Presses within about a second of each other chain together. This is the entire button interface:

1 press

Power off

Only when unplugged and undocked.

2 presses

Nothing

This slot is a sensor calibration shortcut. It is switched off on your units so it cannot fire by accident.

3 presses

Clears the pairing

The tracker forgets its receiver and waits to be paired again. Easy to do by accident, and easy to undo.

4–5 presses

Firmware update mode

The tracker appears on your computer as a USB drive instead of a tracker. Nothing is damaged — unplug it and press the button to come back.

What the light is telling you

These dots blink at the same speed your tracker does. Hold it next to the screen and find the one that matches.

Working normally

One brief flash every ten seconds. This is what you should see nearly all the time. 300 ms on / 9.7 s off

Waiting to pair

A short blip once a second. It is looking for a receiver. 100 ms on / 900 ms off

Powering on

Two quick blinks, then it settles. 100 ms × 2

Powering off

Three quick blinks, then dark. 100 ms × 3

Charging

A slow breathing pulse. 5 s cycle

Fully charged

Steady and dim, not blinking. Constant, low

Battery low

A dim, steady blink. Time to charge. 500 ms on / 500 ms off, dim

Compass ready

Fast, insistent blinking. It has learned enough to correct your drift. 200 ms on / 200 ms off

Something is wrong

A burst of 2, 3 or 4 slow blinks repeating every five seconds. Count the blinks — see Troubleshooting. Repeats every 5 s

Pairing

Your trackers arrive already paired to the receiver in the box. You only need this if one has been unpaired, usually by three accidental presses.

  1. Plug the receiver into your PC and leave it in.
  2. Put the receiver into pairing mode from the SlimeVR server.
  3. On the tracker, press and hold the button while it turns on. Keep holding for a full second past the two startup blinks.
  4. The light drops into a short blip once a second. It is searching.
  5. When it connects you get four quick blinks, then the once-every-ten-seconds working pattern.

Pair them one at a time. Bring up one tracker, wait for the four-blink confirmation, then start the next — doing several at once makes it much harder to tell which one failed.

Wearing and using them

Putting them on

Strap each tracker firmly enough that it cannot rotate independently of your limb. A tracker that slides or swivels reports your strap’s motion rather than your body’s, and no amount of software correction fixes that.

What you need on the PC

A Windows PC running SteamVR and the SlimeVR server, plus your headset. The server is free and open source — download it from slimevr.dev. Your trackers run standard open-source SlimeVR firmware, so they work with the official server exactly as any other tracker does.

Starting a session

  1. Plug in the receiver.
  2. Start SteamVR, then the SlimeVR server.
  3. Power on each tracker. Wait for each to settle into the once-every-ten-seconds pattern.
  4. Check every tracker is listed in the server before you put your headset on.

Compass calibration

Each tracker has a compass, and it is the only thing stopping your body slowly rotating away from where you actually are. It teaches itself as you move.

To speed it up, pick up a tracker and slowly rotate it through every orientation — turn it over, onto its side, end over end, as if drawing a figure-eight in the air. When it has seen enough, the light blinks fast and steadily. That is the signal it has a usable calibration.

If you turn slowly in-game and end up facing the wrong direction, that is a compass problem rather than a tracker fault. Recalibrate away from large metal objects, speakers and magnets — they all pull the compass off true.

Charging

Plug in over USB. The light breathes slowly while charging, then holds steady and dim when full. A full charge runs around 17 to 18 hours of continuous use, measured on real sets rather than estimated from the battery rating.

Troubleshooting

Most common causes first.

A tracker went completely dead mid-session

Almost always the five-minute shutdown. If it lost the receiver — you walked out of range, the receiver was unplugged, the software closed — it powered itself off to save battery.

Press the button to wake it. If it keeps happening in one spot, move the receiver somewhere with a clearer line to you, ideally on a short USB extension rather than flush against the back of the PC.

One tracker will not connect any more

Check the light first. A short blip once a second means it is unpaired and searching — three accidental presses will do that. Re-pair it using the steps above.

If it is on the normal once-every-ten-seconds pattern but still missing from the list, restart the SlimeVR server before touching the tracker.

My computer sees a USB drive instead of a tracker

Four or five rapid presses put it in firmware update mode. Nothing is broken and nothing was erased. Unplug it, press the button, and it comes back normally.

The light is blinking in bursts every five seconds

Count the blinks in each burst. Two, three or four blinks are distinct faults. Power the tracker off and on — a startup fault often clears. If the same count returns every time, tell me the number; it says where to look.

Rapid non-stop blinking that is not the compass signal

Temperature warning. Take it out of direct sun, off any heat source, and let it cool before charging.

My body slowly rotates away from where I am facing

Compass drift. Recalibrate as described above, away from metal and magnets. This is the one problem that is genuinely fixable by you in under a minute.

One tracker runs flat much sooner than the others

Some variation is normal. A tracker that consistently dies hours before the rest is worth telling me about — do not open it, and do not leave it charging unattended overnight. See Repairs.

Specifications

SensorICM-45686 — 6-axis motion, plus a 3-axis compass
LinkDedicated 2.4 GHz radio to the supplied receiver
FirmwareSlimeVR (open source)
RequiresWindows PC with SteamVR and the SlimeVR server
Battery life≈ 17–18 h continuous
ChargingUSB-C
Idle shutdown15 min without motion
Link-loss shutdown5 min without the receiver
ControlsOne button
IndicatorsOne LED

The radio is not Wi-Fi and does not touch your network.

Care