Garmin Forerunner 305 Owner's Manual - Page 63

heart rate zones based on the percentages shown below. For more information on setting your heart rate zones, see page 51. About Pairing Pairing is the process of matching sensors, like your heart rate monitor, with your Forerunner 305. This process occurs automatically when you turn on the Forerunner and only takes a few seconds when the sensors are on and functioning correctly. Once paired, your Forerunner will only receive data from your sensor. Upon power up, the Forerunner will automatically scan for the sensors you have enabled (see "Adding Accessories," page 46). Each sensor has a unique ID. The Forerunner learns and saves this Forerunner® 205/305 Owner's Manual Appendix unique ID while pairing the first time. The next time you turn on the Forerunner, it will only pair with the unique sensor ID. If the Forerunner does not find the sensor, you should restart the scan to find your sensor ID. Interference Strong electromagnetic fields can interfere with your heart rate monitor and cause your heart rate to appear unusually high, freeze, or disappear. Common sources of interference include high voltage power lines, electric motors, computers, televisions, and mobile phones. After you move away from the source of interference, your heart rate reading should return to normal. 59