remote antenna question

Discussion in 'GPS Tracks - Mexico, Central & South America' started by OlyRider, Feb 6, 2007.

  1. OlyRider, Feb 6, 2007
    #1
    OlyRider

    OlyRider Long timer

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    I just purchased a GA25BNC antenna for my 276C. There weren't any instructions. I have a couple of questions. Is there a proper "orientation" for the antenna? (Does the antenna need to be mounted so that it has trhe most surface area facing up?). Is is OK to coil the extra length of wire or do need to route it somewhere? Can I use a couple of zip ties to securely mount the antenna or will the interfere with reception? I can use the 276C without problems, but as my questions show, I have no idea how it all works!!

    Thanks!!
    #1
  2. KTOOMER, Feb 6, 2007
    #2
    KTOOMER

    KTOOMER ad-vent-ure man

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    why did you need the antena?
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  3. Frank Warner, Feb 6, 2007
    #3
    Frank Warner

    Frank Warner Traveller

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    :1drink
    Pointing up is a good idea. Mucho better than pointing down.

    A "loose" coil is fine. Do not force it into a tight coil. Do not clamp the cable tightly .. leave a bit of room so it will not get distorted over time. I had heat shrink on 20 metres of cable (double screened, low vswr .. $$$) the heat shrink held ferrite beads on the outside of the cable .. spaced about 150mm apart .. after a few years in the OZ sun .. the cable had very poor performance around 1 GHz .. due to the repetitive 'crimping' of the cable .. caused by the heat shrink compressing the cable .. so don't do that. :freaky

    Upe .. that won't cause any rf problem .. I assume the base will take the tension?
    #3
  4. OlyRider, Feb 6, 2007
    #4
    OlyRider

    OlyRider Long timer

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    KTOOM asked: why did you need the antena?


    I decided to go with the remote for two reasons:

    1. It is supposed to have much greater ability to acquire the satellites.

    2. The remote antenna is less likely to break than the stock antenna when I decide it is time to perform an endo. The stock antenna also obstructs my view of the R12GS dash where it is located.
    #4
  5. FredRydr, Feb 14, 2007
    #5
    FredRydr

    FredRydr Danger: Keep Back 300 Ft.

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    Is it possible to shorten the 8-foot coaxial cable without affecting antenna performance?

    Fred
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  6. GSbiker, Feb 14, 2007
    #6
    GSbiker

    GSbiker new and un-improved

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    Shortening the cable is fine. Most GPS antenna cables are RG174 coax so you need a new connector that will handle that coax and mate with your GPS. Take it to a good radio shop and they can do it for you for a few bucks.
    #6
  7. FredRydr, Feb 14, 2007
    #7
    FredRydr

    FredRydr Danger: Keep Back 300 Ft.

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    Okay. I thought it would have been shortened at the antenna and resoldered in order to keep the connector, but I know little of this stuff.

    I am contemplating making a plate to hold the amplified antenna immediately above my Garmin Quest cradle, so I'd only need about six inches of cable.

    Fred
    #7