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Is this cable bad?

Discussion in 'CB Antennas' started by TruckerKevin, Jun 11, 2019.

  1. TruckerKevin

    TruckerKevin Active Member

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    I just bought this LMR-400 equivalent and got my antenna permanently raised. My cable was too long going into the house, so I cut the access feet to solder a new PL259 connector on it. Before I do anything I checked the resistance on the center electrode to the outer sheath to make sure I don’t have a short and it goes to zero!

    I tested the other end of the cable (the end I cut off) and it’s fine.

    Someone please tell me it’s because I have the antenna connected to the other end to this cable and it’s 36 feet in the air. If I have to drop this tower after concreted it in and guy wired it, I’m gonna go ape


     

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  2. Robb

    Robb Yup

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    Some antennas have a coil or shunt to tune impedance at 27mhz. SO it will show a short with a DC tester. Remember; the output of a radio is AC - not DC. SO, at 27mhz it will read 50 ohms. To test the cable for a DC short, you will need to disconnect both ends. Suffice to say, that if the antenna was working properly before you cut the end, it is probably OK and so is your cable.
    Which antenna is it hooked up to?
     
  3. Captain Kilowatt

    Captain Kilowatt Professional Amateur
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    It in all likelihood is simply because the antenna is connected at the far end. What is the antenna connected to it?
     
  4. TruckerKevin

    TruckerKevin Active Member

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    It’s one of those old Shakespeare big sticks. Well, since posting this I’ve talked all over to the locals down here any they say I’m loud. I got great swr, even talked a little skip.

    Perhaps there’s not an issue here
     
  5. Captain Kilowatt

    Captain Kilowatt Professional Amateur
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    Yup.....no issue at all. The matching network in the base of the Big Stick is what is showing you a DC short.This is typical of a LOT of antennas. DC characteristics have NOTHING to do with actual RF performance. Some antennas show a dead short while others show a complete open circuit like gamma matched beams. It's all good.
     
  6. TruckerKevin

    TruckerKevin Active Member

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    Scared the hell out of me. I’d hate to have to tell my wife she’s gonna have to climb back up that tower :cheese
     
    hotrod, Robb and Shadetree Mechanic like this.

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