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Sim900A Aerial

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by Wp100, Sep 13, 2017.

  1. Wp100

    Wp100 Active Member

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    Hi,

    Am using a Sim900A module ( firmware reprogrammed for uk use) with its 40mm rubber covered screw on aerial.

    If I enclose it within an abs box will it degrade its performance much ? ( urban use)

    Also will the aerials position, vertical or horizontal affect it ?

    From simple bench tests I have done, not been able to prove anything for sure.

    Thanks.
     
  2. dr pepper

    dr pepper Well-Known Member Most Helpful Member

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    Yes possibly, a simple test you can do is put the box in a microwave with a cup of water for a few seconds, if the box warms up its conductive and unsuitable, I believe some abs contains metals.

    The polarisation of the aerial needs to be the same as the transmitter, this is less critical at uhf, and I assume the 900 means 900mhz.
     
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  3. Wp100

    Wp100 Active Member

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    Not sure which frequency is being used, seems the Sim900 uses 2G, so at could be 900mhz or 1800 mhz with a Tesco Sim.

    Just tried the microwave test, full power for 30 seconds, the water near boiling , the case cold.

    000411.jpg

    000412.jpg
     
  4. dave

    Dave New Member

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  5. dr pepper

    dr pepper Well-Known Member Most Helpful Member

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    If the magnetron in your microwave blasting it with 2.4 gig doesnt warm it up then its probably fine for your application.
     

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