The lab where we regularly test follow the below sequence.
1. Run the peak scan with 10 milli seconds dwelling at each step.
2. Repeat this for 3 or 4 times, because in every run generally some new
frequencies are getting added to the list.
3. Rotate the turn table in steps of 30 deg. angle and in every angle
repeat step 1 & 2.
4. Manually list all the frequencies where the emission peak is near to the
limit line (say about 10 dB margin).
5. Measure the QP for each of this frequency by varying the angle and
height of antenna. It takes about 5 to 7 minutes for each frequency and we
can very clearly see that the QP level is varying drastically. Sometimes I
noticed about 15 dB change. Record the maximum value measured.
6. Repeat steps 1 through 6 for the other polarisation.
Still I see variation in the results between the testing on any 2
days for the same piece of device with same support equipment. And testing
the same set up in another lab puzzled me many times. Frequencies appearing
in one lab will not be seen in the other, level will differ more than 10 dB
at same frequency between the labs, both the labs are accredited.
Sincerely                                                         Â
SCM
Microsystems (India) Pvt. Ltd.
K. Balasubramanian                 Â
                       Modules 0506,
0507 & 0508, D – Block,
Manager – Hardware    Â
                                   South
Wing,
TIDEL Park,
Tel : +91 44 42931391Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
                      #4, Rajiv
Gandhi Road,(formerly Canal Bank Road)
Fax :+91 44
22540029Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
Taramani,
Chennai – 600113. India
E-mail:[email protected]Â Â Â Â Â Â Â Â Â Web :
http://scmmicro.com
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| From: |
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|"Amund Westin" <[email protected]>
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| To: |
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|<[email protected]>
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| Date: |
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|12/04/2008 04:26 PM
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|Radiated emission - time at each frequency
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When doing Radiated emission 30-1000 MHz according to EN55022, for hold
long time do you measure at each frequency (band)?
Best regards Amund
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This message is from the IEEE Product Safety Engineering Society emc-pstc
discussion list. To post a message to the list, send your e-mail to
<[email protected]>
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