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Resonating coax

  • Thread starter Thread starter BOOTY MONSTER
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Hey hookedon6, didn't mean it that way, you are right it doesn't change the accuracy. Was just suggesting that moving the meter to differant places on the transmission line can change the reading a bit. And booty you are right, a 1/2 wave will show an exact reflection of the feedpoint reading. Sometimes by cutting the coax like they are talking about you are changing the way the meter shows and it can actually show a good reading.
 
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WOW!
It is a simple thing to understand that when the antenna is a match to the feedline that the length of the feedline does not matter.
Much of the time the match of the antenna to the feedline is not perfect but if it is close, why bother with line length changes?
If the antenna is not a match, it's the user fault for not assemblying correctly or installing correctly.
Look at an SWR chart vs power to see the effects of SWR.
At an SWR of 2 to 1 you still get 88.9% of transmitter power at the antenna terminal.
At 4 watts or 400 watts 11.1% loss will never be missed at the receiving end and it does not affect receive incoming.
Besides, the missmatch is missmatch.
You are not correcting anything anywhere in the system but allowing the radio to see a near 50 ohm impedence.
It does not fix the original missmatch.
All people do is satisfy seeing a meter reading of near zero that does not accomplish anything.
Good luck.
 
I don't know what is meant by the use of the word resignate. It's either misspelled, or some made up word. The writer of BM's link to a new BM revelation is probably trying to use it to say the word "resonate."

It's all bull shit. No feed line is going to show totally accurate results at the radio end of the line, unless the load end is virtually perfect, and that matches the characteristic impedance of that particular feed line in use...even if you could make a perfectly resonant feed line. Make a change with anything for the system, including height, and it's start all over time.

This statement is being pretty picky and technically precise, but a tuned and resonant feed line will never show perfectly what you imagine, so close is good enough. Even if you could get a perfect match, the difference would be almost impossible to detect, and for sure just using your radio, testing device in line, or a hand held analyzer.

The stub test suggested here proves that the impedance changes with line length...even if the load is as perfect as the typical CB type dummy load can show, and that too is hardly ever perfect. This is why adjusting the match for an antenna is best done right at the feed point, and at installed height.

"...we're just lucky that Mother Nature doesn't require us to get our antenna systems perfect in order to work our radios."
Click to expand...
 
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resignate

verb. To force or otherwise cause the resignation of someone or something. Resignation, meaning to leave a held position, usually of some power.

Pearl Jam's song "God's Dice" (Binaural, 2000): "Resignate my will." ... "Resignate my god."

-----

Resignate actually is a word, but hardly applies to the content of the post. I agree, it's total BS. I didn't realize that 27MHz was a CB channel, but even if it was true what would happen to the 'resignate' coax (at 27MHz) when you changed to a different frequency? :wink:
 
I read the original quote Booty posted, and then I read all the responses. I do believe the use of the word resignate was meant to say resonant/resonate, and I do believe it is a seriously wrong word to use in the context of the process the original author was trying to describe.

I do not know exactly what he's doing, nor do I know how to articulate what I think he was trying to do, but I am completely convinced he was NOT trying to make a tuning stub, nor do I believe anyone here even remotely understood what it was he was doing, nor did anyone unload their predispositions to the notion of feedline length affecting impedence at the feedpoint or the resonance of the antenna long enough to try to figure out whether the author was going anywhere with his project, or why he said those at the receiving end of his TX saw improvement.

I also figure the guy presumed the antenna was resonant, and well tuned before the coax was adjusted, so I don't think that was his interest in tuning his coax to show an apparent 50 Ohms SWR match. There was no antenna hooked to the end of his coax, just a dummy load on the tee which he was apparently only using to tune his coax and would not stay inline when the coax was attached to his antenna. That said, when the dust of the china shop bulls clears around the arena maybe someone will speak to what was posted and not to what they wanted to say because they didn't understand what the guy was doing. I can't do it, maybe no one can.

If this thread survives the ambush I'll check back in later to see if there was a discussion of the material.

Booty, if I knew the answer to what the guy was talking about I'd sure try to tell you. . . I just don't know.
 
here's a link to the "magical coax length" thread that the post was in ...

magical coax length

"What your doing is tuning the coax to match the SWR of your dummy load and will make it resginate at 27mhz just like the dummy load is."

post 16 , page 2

RE's follow up post suprised me over at 11MO about the gain claim was interesting . and i still don't understand what "hard math" is required to calculate a electrical half wavelength , seems much much easier than cut , measure , cut , measure , cut measure .........

"If you do all the hard math to calculate out the Velocity factor of your coax at 27 mhz the numbers always match the leingths doing it this way as well."
 
HomerBB said:
I read the original quote Booty posted, and then I read all the responses. I do believe the use of the word resignate was meant to say resonant/resonate, and I do believe it is a seriously wrong word to use in the context of the process the original author was trying to describe.

I do not know exactly what he's doing, nor do I know how to articulate what I think he was trying to do, but I am completely convinced he was NOT trying to make a tuning stub, nor do I believe anyone here even remotely understood what it was he was doing, nor did anyone unload their predispositions to the notion of feedline length affecting impedence at the feedpoint or the resonance of the antenna long enough to try to figure out whether the author was going anywhere with his project, or why he said those at the receiving end of his TX saw improvement.

I also figure the guy presumed the antenna was resonant, and well tuned before the coax was adjusted, so I don't think that was his interest in tuning his coax to show an apparent 50 Ohms SWR match. There was no antenna hooked to the end of his coax, just a dummy load on the tee which he was apparently only using to tune his coax and would not stay inline when the coax was attached to his antenna. That said, when the dust of the china shop bulls clears around the arena maybe someone will speak to what was posted and not to what they wanted to say because they didn't understand what the guy was doing. I can't do it, maybe no one can.

If this thread survives the ambush I'll check back in later to see if there was a discussion of the material.

Booty, if I knew the answer to what the guy was talking about I'd sure try to tell you. . . I just don't know.
Click to expand...


OK,...... I'll play,..................... if you understand how a multi-band FAN DI-POLE works, why & how the RF "knows" which wire to flow on to.................. then you will also understand what he is trying to do.

the RF wants to "see" 50 ohms , so it goes there vice the non resonant antenna.

but,..................

bottom line: my dummy load is a poor antenna:p
 
i didn't know what he was trying to do till he said
"What your doing is tuning the coax to match the SWR of your dummy load and will make it resginate at 27mhz just like the dummy load is."
then i realized he was doing a lot of physical work to avoid all the hard math to calculate out the Velocity factor of your coax at 27 mhz" ...... which is one simple division and one simple multiplication calculation in order to get a electrical half wavelength .

the gain claims for doing it looked a little bit off though :blink:
 
WR0220 said:
resignate

verb. To force or otherwise cause the resignation of someone or something. Resignation, meaning to leave a held position, usually of some power.

Pearl Jam's song "God's Dice" (Binaural, 2000): "Resignate my will." ... "Resignate my god."

-----

Resignate actually is a word, but hardly applies to the content of the post. I agree, it's total BS. I didn't realize that 27MHz was a CB channel, but even if it was true what would happen to the 'resignate' coax (at 27MHz) when you changed to a different frequency? :wink:
Click to expand...

It is not a word, it is slang, a word created for a song. The Urban dictionary is full of such poetic utterances. I agree the post is BS however, but BM and Bush 43 probably like it, so it's alright by me.

https://www.google.com/#q=resignate....,cf.osb&fp=cbfef847140315f4&biw=1073&bih=498
 
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