Locate EMI in a Home Environment For this project, you will use a portable battery-powered radio to.

Locate EMI in a Home Environment

For this project, you will use a portable battery-powered
radio to locate sources of EMI in a home. You will need a working radio,
preferably one with an external antenna.

1. Tune the radio to a point on the FM band where you cannot
hear a broadcast station with the antenna fully extended.

2. Without moving the tuner control, change over to the AM
band and see if you hear any broadcast AM station. If you do, move the tuner to
a clear point on the AM band and fl ip back to the FM band to see if the tuned
location is clear on that band as well.

3.
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Locate EMI in a Home Environment

For this project, you will use a portable battery-powered
radio to locate sources of EMI in a home. You will need a working radio,
preferably one with an external antenna.

1. Tune the radio to a point on the FM band where you cannot
hear a broadcast station with the antenna fully extended.

2. Without moving the tuner control, change over to the AM
band and see if you hear any broadcast AM station. If you do, move the tuner to
a clear point on the AM band and fl ip back to the FM band to see if the tuned
location is clear on that band as well.

3. Continue this procedure until you find a tuned location
on the radio that has no AM or FM station. Turn the volume of the radio up
high.

4. With the radio at high volume and its antenna extended,
tour the room you are testing, listening for interference that will be audible
as noise (static) on one or both of the radio frequency bands.

5. If you detect interference in the room, move the radio
around until you get the strongest signal. Look for an electrical device that
is operating and could be producing the interference.

6. Tag any suspect devices you fi nd, but complete your
testing tour before attempting to correct any problems you fi nd.

7. If there is no interference in a room when you first test
it, turn on every electrical device in the room, one by one, and check to see
if any interference develops as each device is activated.

8. Tag each device that produces an interference signal on
the radio. Test as many rooms in the house as you wish.

9. How many sources of EMI did you fi nd? How would you
reduce or eliminate EMI in the house?

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