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Thread: uhf aerial short

  1. 13th February 2009, 05:59 PM #1
    lewy
    lewy is offline Wizard Silver Subscriber
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    uhf aerial short

    just fitting a new uhf aerial and cable.when i put my red probe off my multimeter on the centre of the base fitting and the black on the earth side and set the meter to 20 k the readout reads 9.90 this is with the cable attatched to the radio.when the cable is unatched the meter reads 1.is this indicating a short somewere
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  2. 13th February 2009, 06:06 PM #2
    waynep
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    Meter reading 1 indicates infinite resistance or open circuit - so no short there. Set the meter to a lower resistance range and with it disconnected from the radio check there is continuity ( i.e. a few ohms ) between the centre pin of the connector and the whip, and between the outside ferrule of the connector and the steel tube part of the antenna ( assuming you have independent ground plane aerial )

    When connected to the radio the internal circuitry of the radio will present some lower DC resistance. Not sure if 9.9Kohm is typical will depend on the design. But it's not a short.

    Is there a problem with your transmissions or reception ?

    The best instrument for checking your antenna is a VSWR meter, Bird thruline or similar- maybe see if you can borrow one.
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  3. 13th February 2009, 06:17 PM #3
    lewy
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    thanks for that,i cant check transmission quality till tomorrow.
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