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Thread: coax questions....

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    coax questions....

    ok coax question #1. -
    if the length doesnt matter when running a given length of coax
    then why does it make a difference with resonating the length to a given frequency verses the vf?
    also when i use a analyzer i get a different reading than with a swr meter
    Last edited by Mr.5150cbrn; 06-10-2012 at 08:25 PM.

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    your answer is in this thread already on the forum .

    http://www.cbjunkies.com/threads/157...light=velocity

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    also noting that the swr bridge was adding standing wave into the mix

    so with that i tried using a different meter inplace of the other one - different measurements
    neither of which , i may add came to near what the MFJ was saying

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    meters can not measure the impedance and capacitance of the antenna system. They only read fwd and reflected power.
    the mfj can see much more.
    I have personally seen changes in performance by altering coax length. both in the feed line and jumpers.
    Once again real life findings.

    What the average t bag doesnt understand ( resident who ) is each foot of coax has capacitance to it. Jumper length matters due to this!!! it can does and will affect the input or output tuning of the amplifier.

    if you dont use 1/2 wavelength intervals with VF factored in on your antenna, you may as well try sucking a milkshake through 12 in of big straw and then 2 in of a coctail straw. its not optimal. But you dont have to believe me. The ones who dont can go on being the biggest duck they can be.
    by BOOTYMONSTER Tue Nov 11, 2008 2:07 pm
    how about an option to delete a thread we make ?
    ill admit im at least a part time idiot . sometimes i do double post when editing a post .
    some may find this hard to believe , but ....... sometimes i even get pissed and make a post i regret later . hard to believe huh?? lol

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    Quote Originally Posted by coolbreeze View Post
    meters can not measure the impedance and capacitance of the antenna system. They only read fwd and reflected power.
    the mfj can see much more.
    I have personally seen changes in performance by altering coax length. both in the feed line and jumpers.
    Once again real life findings.

    What the average t bag doesnt understand ( resident who ) is each foot of coax has capacitance to it. Jumper length matters due to this!!! it can does and will affect the input or output tuning of the amplifier.

    if you dont use 1/2 wavelength intervals with VF factored in on your antenna, you may as well try sucking a milkshake through 12 in of big straw and then 2 in of a coctail straw. its not optimal. But you dont have to believe me. The ones who dont can go on being the biggest duck they can be.
    what about when you change the channel and it's no longer a electrical half wavelength ?

    so ...... if is not on the one channel that it's perfectly tuned for it will perform as well as "sucking a milkshake through 12 in of big straw and then 2 in of a coctail straw" ????
    since it's no longer a electrical half wavelength because the channel was changed .... ???

    how in the world do hams manage to talk around the world using such wide bandwidth transmitters ?

    don't get me wrong , i am a fan of using electrical half wavelengths of coax centered on your favorite band or most used frequency/channel . i'll disagree on the amount of signal loss you suggest by not having the correct length of coax . and so do millions of other people .
    Last edited by BOOTY MONSTER; 06-11-2012 at 11:44 AM.

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    ok then the meters cant read capacitance or inductance
    but in my findings ( real world ) meters can also add to the swr nightmare by increasing standing waves- some worse than others
    as shown by the readings from the mfj anylizer of the antenna system

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    Quote Originally Posted by coolbreeze View Post
    meters can not measure the impedance and capacitance of the antenna system. They only read fwd and reflected power.
    the mfj can see much more.
    I have personally seen changes in performance by altering coax length. both in the feed line and jumpers.
    Once again real life findings.

    What the average t bag doesnt understand ( resident who ) is each foot of coax has capacitance to it. Jumper length matters due to this!!! it can does and will affect the input or output tuning of the amplifier.

    if you dont use 1/2 wavelength intervals with VF factored in on your antenna, you may as well try sucking a milkshake through 12 in of big straw and then 2 in of a coctail straw. its not optimal. But you dont have to believe me. The ones who dont can go on being the biggest duck they can be.
    You're a Ween

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    Quote Originally Posted by Gordon Gekko View Post
    You're a Ween
    thats right
    and your still in the swamp
    quack quack
    Last edited by Mr.5150cbrn; 06-11-2012 at 08:45 PM.

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    5150 you are correct. A bird meter is the only one I have found that does not affect the antenna line. My freaking dosy adds alot of reflect

    booty when changing channels coax length would be inches different. do you have adjustable coax?
    if your coax is feet off what would be perfect, now thats going to be a change. changing channels is not. bands could be.
    by BOOTYMONSTER Tue Nov 11, 2008 2:07 pm
    how about an option to delete a thread we make ?
    ill admit im at least a part time idiot . sometimes i do double post when editing a post .
    some may find this hard to believe , but ....... sometimes i even get pissed and make a post i regret later . hard to believe huh?? lol

  12. #10
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    Quote Originally Posted by coolbreeze View Post
    5150 you are correct. A bird meter is the only one I have found that does not affect the antenna line. My freaking dosy adds alot of reflect

    booty when changing channels coax length would be inches different. do you have adjustable coax?
    if your coax is feet off what would be perfect, now thats going to be a change. changing channels is not. bands could be.

    adjustable coax ? WTF this smells of some serious 'AMPOWER

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