antenna length?

Discussion in 'CB Radio Forum' started by Elroythekid, Jun 14, 2017.

  1. Night Stalker10

    Night Stalker10 Road Train Member

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    That's like a beam antenna, the last elements are the reflector. Your body was acting like a reflector since u were close to the antenna. I usually don't get too concerned about resistance readings on my MFJ analyzer. They say the 1/4 wave antenna has an impedance of around 32 - 36 ohms. So if u do the math 50/36 = 1.38 or 1.4 for swr reading. Its the reflected power or reactance to be concerned with. Ridgeline can correct me if I'm wrong.
     
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  3. Meteorgray

    Meteorgray Heavy Load Member

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    Quote: ..."I just found it odd how i ha to tilt my meter the same as my ant to get the higher reading."..

    Could this be explained by the polarization factor: the mismatch characteristics of vertical antennas interacting with horizontal antennas?
     
  4. Night Stalker10

    Night Stalker10 Road Train Member

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    That's a good possibility. I think the main reason is because there is no metal under or by the antenna to act as a counter pois (ground plane) to electrically make up the other half of the antenna .... kind of. I give these guys kudos for all the time, research, and $$$'s spent trying to make the antenna work with these new fiber glass trucks.
     
  5. Ridgeline

    Ridgeline Road Train Member

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    Just to clarify something, when you are standing there with a fs meter in hand, your body acts like a capacitor and this changes the reaction with the meter and the antenna of the meter. When I did the cascadia tests, I used fs sensors that were fixed and grounded to give accurate readings.
     
  6. Night Stalker10

    Night Stalker10 Road Train Member

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    Ah yes, I didn't even think about your body acting like a capacitor. That makes sense, I was thinking it had something to do with the counterpoise of the vehicle.
     
  7. rabbiporkchop

    rabbiporkchop Road Train Member

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    The triple X is being built for Jason.
     
  8. Ridgeline

    Ridgeline Road Train Member

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    In reality there is no such thing as a counterpoise in a mobile application, it can not happen because there is earth ground involved.
     
    bored silly Thanks this.
  9. craig_sez

    craig_sez Road Train Member

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    Naw bored silly has one as well..
     
  10. craig_sez

    craig_sez Road Train Member

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    I was
    I was just foolin around in a trk stop..I was cleaning out my closet and saw it in the back...
     
  11. craig_sez

    craig_sez Road Train Member

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    My r is 57 on 26965 and my x was 6...27185 the r is 63 and x is 0 and finally on 27405 r = 71 and x at 0..Thought yhe r ment resistance not reactance..Either way its to high..Ill have to clean up my mounts connections and see it that lowers it any..
     
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