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Best VHF Antenna - Page 2
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Thread: Best VHF Antenna

  1. #16
    Ausfish Platinum Member
    Join Date
    Aug 2001

    Re: Best VHF Antenna

    It goes to show how little is know in relation to VHF antenna. Hight is a big factor but the DB ratting is even more important. Most of the common VHF antenna are rated to 3 db and will range in price from $50 to maybe $90. You wont the highest DB rating you can afford. I have 2 x 6 DB 2.4 meter antenna that I have extended to 3.6 meters in the base. 6 db has twice the punch of the 3 db but you can get 8 db but the price is high. In my last boat I had 3meter 6db antenna and I could reach the coast guard from over the back of the back banks. Hight and power is what you should be looking for.

  2. #17

    Re: Best VHF Antenna

    Quote Originally Posted by DTHCoCo View Post
    VHF may be considered only line of sight but the waves have known to bend slightly and VHF will skip in the lower frequencies which means it isn't line of sight.
    ...are you referring to the 27Mhz band? Because, "skip" as I know it is rare as hens teeth as the frequency increases (I may be wrong mind you). No doubt there may well be changes in atmospheric conditions to allow a brief window to tx at high freqs but I would not rely on these conditions to be perfect when I start making a mayday call...

  3. #18

    Re: Best VHF Antenna

    There is certainly skip at times in VHF frequencies. I have talked to JT once off Yeppoon from off Mooloolaba on 21 which is a repeater channel. That whole morning we got all the boats logging on and off from central Qld down here.

  4. #19

    Re: Best VHF Antenna

    Ive been fishing at cape moreton QLD and heard Ulla dulla coast guard in NSW and quite often get Hervey bay via skip, and i reckon shakespeare make the best VHF aerials around.
    cheers cr

  5. #20
    Ausfish Platinum Member Si's Avatar
    Join Date
    Jan 2009

    Re: Best VHF Antenna

    Quote Originally Posted by DTHCoCo View Post
    VHF may be considered only line of sight but the waves have known to bend slightly and VHF will skip in the lower frequencies which means it isn't line of sight.
    yes this is true. generally you will get slightly more than line of sight due to refraction of the radio waves. if they refract downward towards earth then you can get a bit more distance. it aint that much more though. sometimes atmospheric conditions like temperature inversions increasing refractive index of atmsosphere, e clouds are conducive to skipping of the radio waves but its nothing to rely on. Looking at it conservatively and from a safety view point it is generally line of sight.

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