Saltwater and Plastic Antenna

Discussion in 'Amateur Radio News' started by G4TUT, Sep 21, 2019.

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  1. G4TUT

    G4TUT Ham Member QRZ Page

    Saltwater and Plastic Antenna

    A new antenna that uses saltwater and plastic has been developed by Lei Xing and her colleagues at the College of Electronic and Information Engineering at Nanjing University of Aeronautics and Astronautics in China

    IEEE Spectrum reports researchers have developed an advanced liquid-based antenna system that relies on a readily available ingredient: saltwater.

    The saltwater-based antenna that achieves 12 directional beam-steering states and one omnidirectional state. Its circular configuration allows for complete 360-degree beam-steering and works for frequencies between 334 to 488 MHz.

    The proposed design consists of a circular ground plane, with 13 transparent acrylic tubes that can be filled with (or emptied of) salt water on demand. One tube is located in the center to act as a driven monopole (the radio signal is fed in via a copper disk at the base of the tube). Surrounding it are 12 so-called parasitic monopoles. When only the driven monopole is excited, this creates an omnidirectional signal. But the 12 remaining monopoles, when filled with water, work together to act as reflectors and give the broadcasted signal direction.

    Read the IEEE article at

    KG4BFR, KE8MBH, IU3EJH and 2 others like this.
  2. KA0HCP

    KA0HCP XML Subscriber QRZ Page

    Hence the acronym "HDA" = Hydraulic Defined Antenna. ;)
  3. W1YW

    W1YW Ham Member QRZ Page

    Oh gosh--


    Another PRC 're-discovery'.. can someone kindly dig out the salt water antenna press release from the US Navy, oh, 5-8 years ago?

    IMO this is a giant step backwards in antenna design. Its akin to building a giant telescope mirror from liquid mercury....

    Chip W1YW
    Last edited: Sep 24, 2019
    WQ4G, AK5B, NL7W and 5 others like this.
  4. W1YW

    W1YW Ham Member QRZ Page

    WQ4G likes this.
  5. YY4YJY

    YY4YJY Ham Member QRZ Page

    muy interesante
  6. N7RF

    N7RF XML Subscriber QRZ Page

  7. W4EAE

    W4EAE Premium Subscriber QRZ Page

    Your metaphor, not mine.

    The whole premise of the suggested antenna is that it uses a free, found, and ubiquitous substance for the material of the antenna.
  8. W1YW

    W1YW Ham Member QRZ Page

    No, its your non sequitar.

    Plexiglas (polycarbonate) is neither free nor ubiquitous.

    I have no idea what you mean about 'found'.

    The cost is HIGH. A polycarbonate fat tube for shortened 2M salt water antenna costs about $60; is corrosive, and a mess. Wire costs $0.70

    I know. Here's one I did 12 years ago--at least the tube for it.

    None of this stuff is new or particularly, uniqely useful. Lotsa downsides---and a mess.

    We are not going back to the days of 'wet' mason jar analogy.
    Last edited: Sep 25, 2019
    K4AGO likes this.
  9. W1YW

    W1YW Ham Member QRZ Page

    Here's a DIY 'wet capacitor'...

  10. WQ4G

    WQ4G Ham Member QRZ Page

    Next thing you know, Chip, they'll be trying to use a tree as an antenna. Wink, wink...

    K4AGO and W1YW like this.

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