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Frequently Asked Questions

Absolutely. FlexVolt sensors use the EMG signals from your muscles to give you an objective measure of your muscle tension. Monitor tension as you go through relaxation exercises, or set thresholds in the FlexVolt app to alert you when your muscles are becoming too tense.
FlexVolt is not certified as a medical device nor should it be used to diagnose or treat medical conditions.
The FlexVolt project started with a desire to alter human-machine interaction and initial prototypes were developed as a way to interact with computers via muscle signals. However, after product demos and interactions with physical therapists and biofeedback specialists, it became clear that FlexVolt also fills a need for affordable EMG sensors.
Electromyography is not new, but the currently available systems are complex and expensive and usually only seen in medical centers or research laboratories. FlexVolt breaks those barriers to make EMG and biofeedback accessible to everyone. The FlexVolt is a first attempt at reaching a loftier goal – making biomedical technology affordable and available for in-home use.
The Myotrac EMG sensor is one of the only other home-use biofeedback sensors on the market. It offers feedback via sound or LEDs, but does not interface with mobile devices. At $500 for a single-channel sensor, it is significantly more expensive than FlexVolt.
Yes. FlexVolt sensors are battery powered, and the sensor circuitry is automatically disconnected when charging the battery. This means that there is never a potential for electrical connection between the patient and building power sources.

Trouble Shooting

If the green LED does not light up when you flip the switch: 1. Try charging the battery by plugging in the USB cable. Does the red LED light up? If yes, it's charging. Maybe the battery was dead. 2. If the sensor is not charging or turning on, grab a small screw driver, remove the screws from the case, and make sure the battery is where it should be and the clips are in good contact. You may need to bend the clips in a little. Sometimes in shipping the battery gets knocked loose or the clips get bent!
1. Ensure your sensor is charged and turned on (obviously!) 2. Ensure phone/computer is paired with sensor. The apps cannot find your sensor if it is not already paired. Pairing code = '0000'. You may need to turn bluetooth on/off on your phone/computer to refresh available devices. 3. Go to the 'Connection' page in the app, try 'Scan'. This will automatically try to connect to any paired devices, and will find your FlexVolt sensor if it is available. 4. If 3 fails, manually select your sensor from the list. 5. If none of these steps worked, turn your sensor off, unpair/forget the connection on your computer/phone, turn off bluetooth on your computer/phone. Then turn the sensor on, turn your bluetooth on, and try to pair again.
Poor electrode contact, poor reference contact, use of wrong channel, or high levels of RF interference can all attribute to poor signal quality. 1. Make sure you are using at least one reference electrode (the white clip). 2. Make sure you are using the correct channel. Go to settings and set 'Channels' to max for your sensor (2/4/8). In 'RMS' mode, turn on all channels. You should see signal spikes if you bring a reference clip and red/black clip into contact, or clip them both to a metal object, or touch the metal parts on both with your finger. 3. Make sure the sticker electrodes you are using are fresh, you cleaned the skin surface first to remove dirt/oils/hair, and the lead wire clips are in good contact with the sticker electrodes.