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please help antenna issues...

Ok i m getting ready for my setup but the most importent thing is not working stupid truck i hate it arghhhh...

So i was sitting and asking my self whats the problem everywhere i try either the antenna is to tall or something is in the way so i said well i drive a flat bed 99 % of the time i m not fully loaded so sticking the antenna behind the cab in between the trailer should work..someone help me or else i give up..
put it on the mirror and run a ground semi trucks have too much fiberglass then make sure your radio is also chassis grounded dot use your ground wire of course it has to go to the battery, ground the chasis of the radio and run a good ground to the antenna. I dont know what ant your using but generally coax for 11 meters seems to work best when the length can be divided by 3 equally
 
I dont know what ant your using but generally coax for 11 meters seems to work best when the length can be divided by 3 equally
Here we go.

73
Jeff

I saw that earlier today, something like three or four hours ago. I'm surprised no one has responded to it yet.

I ask wheelman918 this. What, in your mind, makes a multiple of three so great? And there is the important question, three what? Three meters? Three inches? Three random lengths added together? Also, how does this rule apply to feedlines with different velocity factors?

I will say only this. Minor changes in the length of a coax will have no affect on the antenna, its tune, and how well it works. If this is not true in your case then you have a problem with your antenna system that you need to deal with. Also using some specific length, or length multiple, of coax is not a fix, it simply hides the problem, it does not solve it.


The DB
 
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I saw that earlier today, something like three or four hours ago. I'm surprised no one has responded to it yet.

I ask wheelman918 this. What, in your mind, makes a multiple of three so great? And there is the important question, three what? Three meters? Three inches? Three random lengths added together? Also, how does this rule apply to feedlines with different velocity factors?

I will say only this. Minor changes in the length of a coax will have no affect on the antenna, its tune, and how well it works. If this is not true in your case then you have a problem with your antenna system that you need to deal with. Also using some specific length, or length multiple, of coax is not a fix, it simply hides the problem, it does not solve it.


The DB
coax on a mobile equally divided by 3 feet increments into its overall length for 11 meters works to perfection has for me on several setups, maybe an indicator why store bought jumpers are all 3 feet? i know this works and i wont swallow no mit bullshit version of why it wont.
 
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coax on a mobile equally divided by 3 feet increments into its overall length for 11 meters works to perfection has for me on several setups, maybe an indicator why store bought jumpers are all 3 feet? i know this works and i wont swallow no mit bullshit version of why it wont.

Forget it guys. Another case of "don't know and don't want to know". It works for him and that's all that matters. The fact that the theory is all wrong and that it is a poor band aid solution to proper impedance matching simply done because the real theory behind the problem is completely foreign and unknown to him means nothing at all. Yes it results in a better match but we will not confuse him with facts about efficiency and better ways to do it or that it is simply compensating for a poorly designed piece of gear that does not exhibit 50 ohms impedance. Remember, MIT is just some place that spews BS.


BangingHeadAgainstKeyboardStreetSig.gif
 
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coax on a mobile equally divided by 3 feet increments into its overall length for 11 meters works to perfection has for me on several setups, maybe an indicator why store bought jumpers are all 3 feet? i know this works and i wont swallow no mit bullshit version of why it wont.

So it appeared to work for you in the past and that is all you have to go on? You did note the word appeared? That is the key word of the sentence. If you fixed the actual problem your antenna system would have worked even better. Your loss I guess...

MIT bs? None of that from me. I'm entirely self taught.

Forget it guys. Another case of "don't know and don't want to know". It works for him and that's all that matters. The fact that the theory is all wrong and that it is a poor band aid solution to proper impedance matching simply done because the real theory behind the problem is completely foreign and unknown to him means nothing at all. Yes it results in a better match but we will not confuse him with facts about efficiency and better ways to do it or that it is simply compensating for a poorly designed piece of gear that does not exhibit 50 ohms impedance. Remember, MIT is just some place that spews BS.


BangingHeadAgainstKeyboardStreetSig.gif

I figured as much when I wrote that response. I was trying to see if he had some explanation as to why his theoretical three foot multiple lengths worked. Even if he were wrong he would have garnered some respect from me for trying. At that point, if he tried, understanding could be given.

Instead he did a great job of digging his own grave...

Wheelman918. As I think you were legitimately trying to help I'll leave this bit of advice for you. Take it or leave it.

This is a very technical oriented forum, especially when it comes to antennas. There are people that frequent both the Ham Radio Antennas and CB Antennas sections that are/were actual broadcast engineers. There are others that, like me, are completely self taught, or may even have some training in college that benefits their knowledge of antennas. This is by far the most technically oriented of any forum that covers CB antennas in general that I am aware of, and I am on several. There are discussions that number well past 10 pages that happen regularly on discussing how certain antennas work, and one antenna specifically has several hundred pages combined in various threads, and these are just the public pages, not including private conversations.

If I chose to explain why the three foot multiple didn't actually fix the problem, for example, it may not affect you and your attitude on the subject, but how would others that read it see you and your insistence of pushing information that you not only don't understand, but don't want to understand, yet you still insist is true?

I can tell you, using your example again, I've seen it appear to work as well. As a matter of fact, one test I do on antennas after I set them up is to change the coax length and see if it changes anything noticeably, and if it does I know there is something else that needs to be addressed. What you call a solution is nothing more than an indicator of a problem to me and many others on this forum.


The DB
 

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