BTLE Sensor generates readings without being connected to my ear (aka: Ghosting)

The issue you’re describing, often referred to as “ghosting,” can sometimes occur when the sensor is not properly attached to your ear or another part of your body. In this situation, the sensor may still display fluctuating values even though no real heart signal is being detected. What you’re seeing in those cases is not an actual heart rate reading — it’s simply the sensor’s electronics reacting to background electrical noise or random fluctuations in light.

From a technical standpoint, this happens because our sensors are designed to operate with very high sensitivity to accurately detect heart rhythm patterns (HRV). While standard heart rate monitors sample at around 20–40 samples per second, HeartMath sensors operate at a minimum of 125 samples per second. This higher sampling rate allows for greater HRV precision, but it can also make the device more susceptible to random beat frequencies when not in contact with the body.

To adapt to the widest range of skin types and pulse strengths, the sensor automatically adjusts its signal strength. It uses pulse width modulation (PWM) to control the LED brightness and fine-tunes the input amplification across 32 different gain settings. This “automatic gain” system is intentionally very sensitive, so when it’s not reading a real pulse, it may still appear to produce activity — this is what’s known as ghosting.

Please note that this behavior is completely normal and does not indicate a defect. It’s simply how the electronics behave when searching for a signal in a closed-loop condition without an actual pulse to lock onto.

Once you attach the sensor correctly to your ear, it will begin detecting your true pulse signal, collect about 64 seconds of real data, and then display your actual heart rhythm and coherence.

So, you can rest assured — as long as the sensor is properly attached during your sessions, the data you see represents your real heart activity.

If you continue noticing unusual behavior while the sensor is properly connected, please let me know — I’ll be happy to guide you further.