Connect with us

SSB question

Discussion in 'Boat Electronics' started by just me, May 19, 2006.

Scroll to continue with content
  1. just me

    just me Guest

    I'm preparing to install a SSB and have been advised to hold the antenna
    cable off the backstay an inch or so until it actually connects to the
    backstay above the lower isolater. Any ideas what I might use for
    standoffs?
    Thanks

    --
     
  2. Small blocks of teflon work well, as do plastic clothspins....

    Bruce in alaska
     
  3. Lynn Coffelt

    Lynn Coffelt Guest

    or.............. short lengths of 1/2" PVC (or other small plastic tube)
    used as a stand-off. Tying the GTO-15 antenna cable to the lower backstay
    with black, UV resistant nylon ties, both legs of the tie running through
    the short tubes. (and around both the backstay and the antenna cable, of
    course). That way you can choose, or easily change the clearance distance to
    whatever you can live with.
    Old Chief Lynn
     
  4. Lynn Coffelt

    Lynn Coffelt Guest

    Sounds great, Mark!
    As a practical matter, having the backstay isolator mounted lower won't
    change the effective antenna length much at all, since the radiating antenna
    length starts right at the antenna tuner, and includes the entire length of
    the feedline as well as the backstay.
    The only difference might be the added capacity to ground for the
    distance the antenna feedline and the lower, grounded part of the backstay
    are parallel. The reduction in that capacitance (and slight radiation
    pattern alteration) is why most installers recommend some sort of spacing
    between the two where they run near each other.
    Old Chief Lynn
     
  5. Bike shops sell plastic clips for attaching tire pumps and cable clamps etc.
    Some of these may be the right diameter for your purpose.
     
  6. And just where did you learn your RF Electronics? The length of the
    antenna starts at the HV Connection of the Antenna Tuner, and ends at
    the farthest point of the wire at it's insulator. It makes very little
    difference to the radio if that is mostly Backstay, or GTO-15 feedline.
    It is the totality of the wire that counts, not which section is which.
    Just how close any one section gets, to any Grounded item, is also
    somewhat important, as this adds Output Capacitance to the tuners
    constraints and can cause the tuners autotune algorythem to do funny
    things, if there is to much.

    Bruce in alaska
     
  7. The backstay should not get thermally hot while you are transmitting -
    but it may be electrically "hot" - anyone touching it while you are
    transmitting may get a nasty RF burn - the "reachable" portion of the
    backstay (and any other part of the antenna wiring) should be
    electrically insulated to prevent shock or RF burns, not because of
    any temperature concerns.



    --
    Peter Bennett, VE7CEI
    peterbb4 (at) interchange.ubc.ca
    new newsgroup users info : http://vancouver-webpages.com/nnq
    GPS and NMEA info: http://vancouver-webpages.com/peter
    Vancouver Power Squadron: http://vancouver.powersquadron.ca
     
  8. That is one of the neatest installation I have found and will probably use
    it unless I can find a product I saw at the Annapolis show a few years ago.

    It was a black plastic extrusion about 2" wide. Along the edges was a
    series of C shape clips about 2" long spaced about 6" apart. One side was
    just large enough to snap over the GTO and the other that snapped over the
    back stay. Neatest installation I have ever seen but I have never been able
    to find a source.

    --
    Glenn Ashmore

    I'm building a 45' cutter in strip/composite. Watch my progress (or lack
    there of) at: http://www.rutuonline.com
    Shameless Commercial Division: http://www.spade-anchor-us.com
     
  9. Larry

    Larry Guest

    It won't if you turn off the big linear and just run 150 watts from the
    radio...(c;

    Sorry, Peter, I couldn't help myself...(c;

    73 DE W4CSC/MM2
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-