Antenna grounding mystery-- help!

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by W6IWW, Jun 12, 2018.

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  1. W6IWW

    W6IWW XML Subscriber QRZ Page

    OK, fellow hams, please tell me why I can't figure out what is probably something simple. I have an HF hex beam that I have used for 5 years. I recently put a new pl-259 on the home end... and it went dead. I figured I screwed up the connector. Did it two more times... dead again. I checked for a short in the cable. There is none. BUT fooling around with the connection I found the antenna basically worked so long as the ground shield was NOT connected. Connect the shield, and, poof! Dead again. What am I missing??
     
  2. W1BR

    W1BR Ham Member QRZ Page

    Assuming it was working immediately before replacing the connector, I would say you have a short when the cable is attached. Not connecting the braid allows the entire run of coax to work as a long wire antenna.
     
    NH7RO, KI5AAI and W6IWW like this.
  3. WB2WIK

    WB2WIK Platinum Subscriber Platinum Subscriber QRZ Page

    ^I agree.

    Possibly an intermittent short that only actually short-circuits when you hold the connector a certain way. It only takes a single strand of the copper braid, which may move a bit when you bend the cable near the connector, to short it out.

    I'd clip an Ohmmeter across the center conductor and shield at the cable then bend the connector various ways to see if the meter ever moves off "infinity."
     
  4. AA7QQ

    AA7QQ Ham Member QRZ Page

    Dig out a 1kohm resistor & put it at the antenna connections to see if you can read it with an ohmmeter.
    Also, ALWAYS check that the ohm meter is functioning properly, by touching the leads.
    Some never realize the fuse blew after trying to measure voltage, while still in the ohm setting.

    Ed
     

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