Status LED - Indicates the status of the Headset connection

• Off: Extender is switched off.

• Green: Extender is on, but it is not recording.

• Orange: Extender is on, it had detected the headset, but it is not recording to the SD Card

• Solid Red: Extender is on and it is recording to the SD Card

• Blinking Red: Extender is on, and is finishing writing on the SD Card. This corresponds to when, after the recording is turned off, the Extender needs to flush the data and close the file on the SD Card.

• Fade on/off: firmware update failure

Power LED - Indicates the status of the Extender

• Off: Extender battery is not charging either because the Extender is not plugged into a charger or because a charging fault condition has been detected.

• Blinking Orange: Extender battery is charging at 100mA.

• Solid Orange: Extender battery is charging at 500mA.

• Red: Extender battery is charging at 1A

• Green: Charging is complete

The Extender has been designed to be small enough to fit into the pocket of a shirt or attached to a lanyard. It features two USB ports which are electrically isolated to connect to a headset and your computer. When connected the headset should be visible in in all EMOTIV software. It features one button for both power on/off and recording start/stop functionality. A microSD card slot is located on the side to allow users to fit a card to store recordings for offline analysis.

There is a hardware trigger input utilizing a 2.5mm audio socket pictured below.

Extender is shipped with a charged battery as per regulatory requirements. We recommend customers fully charge their Extender before first use to provide the best user experience. If you are only using it in pass-through mode this is less important.

The Extender will charge when it is connected to a PC or to a DCP (Dedicated Charging Port) and it will automatically select one of 3 different battery charging currents depending on where it is connected. The USB 2.0 standard specifies that a device should not draw more than 100mA until the port is enumerated and then limited to 500mA. A dedicated charger such as one designed for a phone can supply 1A. The following table details how this selection will be performed.

Headset power and charging

When a headset is connected, Extender will supply power via the USB connector to ensure that the battery in the headset is not depleted. In order to save power, Extender will turn off power to the headset USB connector as described by the following table. It is possible to charge a headset and Extender at the same time if they are daisy chained together, however it will be quicker to charge the headset connected directly due to limited current on a USB port.

It is important to turn on Extender first before connecting the headset because when Extender is off it is not be able to detect a headset connection.

If Extender is turned on and the headset is connected, Extender will set the charging current for the headset battery by sending the appropriate command through the USB connection. The charging current of the headset depends on the state in which Extender is operating as illustrated by the following table.

Extender only has one button for both waking it up from sleep and recording. The table below outlines the behaviour.

Please note Extender will automatically sleep after 30 seconds if it is turned on but not connected with a headset or PC. Extender will automatically sleep if the battery is low and will blink the power LED before switching off.

The table below explains the push button behaviour: