Sailing Boat Antenna Help

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by 2E1HPS, Apr 21, 2020.

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  1. 2E1HPS

    2E1HPS Ham Member QRZ Page

    Just as a side note have been away from amateur radio for many years and am now remembering why it's so great. It's a great challenge bet even better are the great helpful people
     
  2. KL7AJ

    KL7AJ Ham Member QRZ Page

    From The Opus of Amateur Radio Knowledge and Lore.......just for you!



    We’re almost there. Item eleven, drowning, awaits our attention. This hazard is akin to the car crash hazard, but with a twist.

    There is no better place on earth to do some serious hamming than on the high seas. The seafaring ham has a perfect grounding system, something his landlubber kindred can only dream of. Salt water is a conductor, and for the most part, good conductors make good antennas. (The relationship between good antennas and good grounds is a complex one, which we will discuss thoroughly in later chapters.) Suffice it to say that ham radio is good when you’re at sea.

    The problem is that it seems a lot of hams who sail are a lot better at hamming than sailing. Or, perhaps, when faced with such idyllic conditions, hams are just more likely to be concentrating on their hamming than their sailing. The seafaring ham should always be aware that he is on top of a body of water, which, except for relatively short periods of time, is not conducive to human life. He should always wear a life preserver, and have foul weather gear handy. He should have a shipmate that really knows the ropes, in case he doesn’t himself. He should, ideally, know how to swim.

    Lightning and sailing seem to be attracted to each other, as well. This is not a recent discovery. St. Elmo, the patron saint of Ancient Mariners, is also the namesake of St. Elmo’s fire, a phenomenon now recognized as corona——a plasma discharge on ships’ rigging, caused by the proximity of lightning. Perceptive sailors for centuries have recognized St. Elmo’s fire as a warning to go below decks, batten down the hatches, and if necessary, throw disobedient prophets overboard. Modern seafaring hams, on the other hand, typically see St. Elmo’s fire as a sign that they should shinny up the aluminum mast and readjust their antennas. Such hams are likely to suffer the dual indignities of being fried and drowned.

    Is it worth it? Probably.
     
    AK5B likes this.
  3. 2E1HPS

    2E1HPS Ham Member QRZ Page

    Thanks so much for that. It was good to read. In an earlier life I was a deck officer on deap sea oil tankers. One night I remember seeing St. Elmo’s fire and it was one of the strangest things I think I have ever witnessed. Just wish when I was at sea I looked more closely at the antennas.
     
  4. N8TGQ

    N8TGQ Ham Member QRZ Page

    What have you tried so far? If you're just receiving, simply clipping your antenna lead to the rigging may be all you need. Plus its easy to disconnect when not in use and avoid lightning altogether.
    Thanks for the info on the frequencies you want to use. Im gonna copy those and do some listening myself!
     
    AK5B likes this.
  5. 2E1HPS

    2E1HPS Ham Member QRZ Page

    Up to now I have only been using a Icon VHF and a NASA marine navtex. Unfortunately the NASA marine navtex stopped working and the antenna vanished one day in the boat yard. That was what inspired me to go down a different route and get myself the RSP1a as it sounded really interesting. So really I'm right at the beginning.
    Just a couple of final Q,s
    1. If I use a magnetic loop antenna would I have to turn it to listen to the 490khz/518kHz navtext station or will I get a good signal regardless of relative direction.?

    2. Witht magnetic loop will I have to mount it away from the VHF antenna so I don't damage it when I transmit on 25w.
    3. Is there a magnetic loop you would recommend for the navtex? frequencies
     
  6. KL7AJ

    KL7AJ Ham Member QRZ Page

    I've had all those frequencies in my memory channels for ages. Great listening when the rest of propagation is down the tubes. The 8MHz range almost always has some activity. I like getting the Kodiak CG weather fax.
     
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  7. 2E1HPS

    2E1HPS Ham Member QRZ Page

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  8. KL7AJ

    KL7AJ Ham Member QRZ Page

    The magnetic loop is FAIRLY non-directional except for the two very sharp nulls perpendicular to the plane of the loop. I've built all my small loops from scratch. myloop.jpg
    You can tune the loop with a variable capacitor, or for one frequency, use a fixed mica cap (value determined by experiment...and a grid dip oscillator)
    It's NOT absolutely necessary to shield the loop, but it will give you a better null, if in the presence of other metallic objects.
     
    AK5B likes this.
  9. KL7AJ

    KL7AJ Ham Member QRZ Page

    Also, since you're a G-land ham, you'll get a kick out of this. I've posted this elsewhere recently, too:
     
  10. 2E1HPS

    2E1HPS Ham Member QRZ Page

    Great thanks. Good news that a loop is fairly non directional.
    Would it be possible to tune the loop by experiment using a veritable capacitor. Then when it's set to the optimum for one frequency, remove it and meashure the capacitance that it is set to, then buy a mica cap closest to that value.
     

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