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SMA connector check

Discussion in 'Standard/4k Discussion' started by Clive3465, Dec 10, 2015.

  1. Clive3465

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    After completing by new dbs antenna modification to my DJI P3 Standard, I decided to carry out a continuity check on my both my newly fitted 2 number 2.4 WIFI video SMA connectors and 5.8 TX SMA connector. My meter shows a continuous circuit from the centre pin and outer perimeter of both the SMA connectors on my 2.4 WIFI video but does not show a continuous circuit from the centre pin to the outer perimeter of my 5.8 TX SMA connector.
    Is this reading as it should be?
     
  2. kenwhite

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    If both ends of the coax are disconnected, the center pin to connector should read an open.

    You cannot really test the coax connected to the antenna since it may have an inductive feed-point element associated with it.
     
  3. Clive3465

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    So could that explain why I'm get a continuous circuit on both my 2.4 and not on my 5.8?
     
  4. kenwhite

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    Just disconnect both ends of the coax and test.

    That way you will know exactly what you are testing.
     
  5. Clive3465

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    I should also explain that the SMA connectors I am testing are fitted to the RC casing and wired back into the internal mini PCI base connection points. I am testing the circuit without the connecting cables from the SMA connectors to the dbs antenna.
     
  6. kenwhite

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    You can't test the cables that way, they need to be disconnected.

    Plus depending on the ohm scale, and type of meter, you may damage the output device by creating an over voltage condition from the meter.
     
  7. Clive3465

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    Thanks Ken, advice much appreciated !