Making Wire Antenna Insulators

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by KC8VWM, Oct 31, 2017.

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  1. G3YRO

    G3YRO Ham Member QRZ Page

    Yes but I'm not convinced that ANY of these moulded insulators - whether, glass, ceramic or plastic - are actually any better than the Polyester cord I use.

    By the way, although Nylon cord looks similar, it's not so suitable, as it absorbs water)

    Roger G3YRO
     
  2. WB2WIK

    WB2WIK Platinum Subscriber Platinum Subscriber QRZ Page

    I've had polyester (well, double braided Dacron) cord catch fire and melt when tied to one end of a dipole antenna, transmitting with a kW, and during a rainstorm.

    It's funny this has happened not once, but twice, to me and only when it's raining. When the WX is dry it never happens. It only rains here maybe 15-20 days a year or something, so the odds of it raining and my being on the air and transmitting aren't so great, but it has happened.

    The cord self-extinguishes, and once I actually watched it happen. It flames, then burns and melts and breaks the rope at the knot, then everything falls down and the flame simply extinguishes so it doesn't spread to anything else.

    I use good insulators now, and this has never happened again.
     
    N4MTB, WA7PRC and AK5B like this.
  3. WB2WIK

    WB2WIK Platinum Subscriber Platinum Subscriber QRZ Page

  4. N8CMQ

    N8CMQ XML Subscriber QRZ Page

    Hi Roger, the story for the egg insulator is the failsafe if the insulator breaks, the loops keep the antenna up, if the egg insulators were used correctly. My belief is, the insulator works better in compression, like concrete, rather than in tension.

    Both reasons make a bit of sense, as does wire tied to poly rope, if it is OK for an antenna to fall if the rope or wire fail at the joint, you shouldn't need an insulator.

    However, my vertical guys caused the SWR to go crazy the last time it rained. The guys are poly rope, and I am looking for something that does not hold water.
     
  5. KA9JLM

    KA9JLM Ham Member QRZ Page

    Around here they sell the chickens that lay them too. :)
     
  6. KA0HCP

    KA0HCP XML Subscriber QRZ Page

    Why do you think Rubber Chickens have always been so popular!
    [​IMG]
     
  7. AK5B

    AK5B Ham Member QRZ Page

    Google Spectra line; that might be the perfect solution.

    73,

    Jeff
     
    KC8VWM likes this.
  8. AK5B

    AK5B Ham Member QRZ Page

    By the way, although Charles (the OP) didn't specifically say these cable tie insulators were for portable/QRP ops I believe that was his general intent as exemplified by his many portable antenna designs he often comes up with here.

    73,

    Jeff
    Vice President
    VWM Industries
     
    KC8VWM likes this.
  9. G3YRO

    G3YRO Ham Member QRZ Page

    Curious . . .

    As I bet it rains a lot more here in England . . . yet in 40 years of using Braided Polyester cord on the end of several different resonant half wave dipoles (160 to 20m) without any other insulators, I've NEVER had any problems ! (I currently run a TL-922)

    By the way, I'm not trying to be argumentative . . . just passing on my experience.

    Roger G3YRO
     
    W2VW likes this.
  10. WA7PRC

    WA7PRC Ham Member QRZ Page

    Same here... the best $3/insulator (approximately one microbrew beer/insulator) I've spent. :)
     

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