...other person with heart rate monitor is causing interference?
Keep a distance from your training partner and continue your training session normally.
Or
1.Take the transmitter off your chest for 30 seconds. Keep a distance from your training partner.
2.Put the transmitter back and bring the receiver up to your chest near the transmitter’s Polar logo. The receiver starts looking for a heart rate signal again. Continue your training session normally.
...heart rate reading becomes erratic or extremely high?
You may have come within range of strong electromagnetic signals which cause erratic readings. Check your surroundings and move further away from the source of disturbance.
...the display is blank or fading?
If the display is blank, activate the wrist receiver by pressing the OK button twice, after which the Time of Day display appears. The first sign of a discharged battery is the battery symbol on the display. Also the digits fade when the backlight is used. Have the batteries checked.
...there are no reactions to any buttons?
Reset the Polar heart rate monitor. Resetting clears watch settings which will return to the default settings. User information and measuring units settings will be saved.
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