BT47i Exercise Heart Rate sensor User’s Guide
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Using of the Exercise Heart Rate Sensor
1.
Connect the receiver to one of the interface inputs.
2.
Attach the transmitter to the elastic strap.
3.
Adjust the strap length to fit snugly and comfortably. Secure the strap around
your chest, below the chest muscles. Lock the buckle.
4.
Lift the transmitter off your chest and wet (saline solution) the grooved electrode
areas on the back of it.
5.
Check that the wet electrode areas are firmly against your skin and the logo is in a
central upright position.
Helpful Tips
•
It is important to have a good contact between the transmitter belt and the test
subject. The belt must fit snugly, but not too tight. Both electrodes should be wet
with either a saline solution or contact lens solution (most conductive solutions
will work). A 5% salt solution works well and can be prepared by adding 5g of
NaCl per 100 ml of solution.
•
Be sure to hold the receiver within 80-‐90 cm of the transmitter. This is the
maximum transmission range of the transmitter in the chest belt.
•
Computers or mobile phones can be sources of electrical interference. Keep the
receiver as far as possible from such devices.
•
The receiver will receive signals from the closest transmitter source.
•
To avoid confusion or erroneous readings, have test subjects from different lab
teams stay at least 2 meters apart.
•
Typical symptoms of inadequate contact with the electrodes are a noisy signal
with erroneous peaks, missing heartbeat readings, or a flat-‐line display. If the
students receive a flat reading with no heart rate detected then the transmitter
and the receiver have to be moved closer together. If there is still no good
pattern, tight the transmitter belt and/or place 2-‐3 drops of saline solution on
each of the electrodes of the belt.
•
Store the belt dry. Never store the transmitter wet. Sweat and moisture can keep
its electrodes wet and the transmitter activated, which shortens the battery life.
Do not use alcohol or a solvent-‐based detergent.
Suggested experiments
•
Compare the heart rate of different individuals.
•
Check the person’s heart rate before, during and after a short period of vigorous
activity.
•
Monitor the recovery rate: that is how fast a person’s heart rate returns to
normal after exercises.
