Antenna light issue on cobra 29

Not to step in here but i noticed the Wilsons come with a 49 inch whip for the 5 or 10 inch shaft models.
On my 10 inch shaft Wilson i ended up cutting about 6 inches of the whip to get the SWR at 1.2.

The RF ground to the power ground is probably what is messing it up......Just my opinion,I'm not a radio pro but have installed many antennas.

He also stated he is running the factory coax.That would be the first thing to get changed.

 

I agree except for the 49 inch whip. The 'Trucker 2000 & 5000 10" Shaft' states 49.5 inches on the Wilson page I linked on my last post, for CH 19. Since new they are usually 3 or 4 inches too long to begin with I'd have to say more like 54 inches new not 49 as you stated. No doubt factory coax is poor. Some Mini 8 would be better. I still have to wonder exactly where on the antenna did he connect his ground. So hard to diagnose when you cannot see and specific info is lacking. I am sure he has poor ground but I do not agree with the method he used trying to improve it. A picture of the mirror mount assembly in detail would be very helpful. Hard for him to diagnose when he can only look within 40 channels and likely his stinger is inches too long. An Analyzer is so useful since you can sweep MHZ looking for the actual resonant dip.

 

( ME: ) WOW! I DON'T KNOW WHERE TO BEGIN:


( OutLaw ) I can see physics is not your strong point. No you don't know me nor how many years I have worked in RF. The main de-tuning is due to capacitive loading when his hand is around the coil. His body is not significantly having any effect on the magnetic field around the coil. No mystery,
( ME: ) My Daddy always said It's one thing to have people think you don't know what you are talking about it's a whole other thing to open your mouth and remove all doubt !! And you have just opened your mouth.


( ME: ) First I don't know why you brought Physics or magnetics into it, But you did, of course a magnetic field is set up whenever a voltage is feed through a wire or coil/inductor and the strength of that magnetic field depends entirely on the force or volume of that electrical current. But I never mentioned magnetics and I don't know why you did.


( ME: ) Now as usual when someone brings up the big word "PHYSICS" they usually think that is a word that will strike fear into hearts of there enemy and most often this done by someone that had to look it up to make sure it was spelled correctly.


( ME: ) Then they start throwing all kinds of technical jargon around to try to impress everyone with there vast knowledge, But just like people trying to use big fancy words they don't really understand they almost always use them in the wrong context.


( OutLaw) I have never met people who can stick magnets to their forehead. Read about them in tinfoil hat magazine, just never met them. If people were attracted to magnetic fields having a CAT scan would be a horribly life ending experience. In short his body is not ferromagnetic therefore he cannot significantly affect the magnetic field around the coil.
( ME: ) Trying to relate this to a CAT SCAN IS PRICELESS. It tells me you have no Idea what you are talking about. A CAT scan uses Xrays that are analyzed and arranged in slices it's called tomography I learned that in 8thgrade physics...And by the way I used to service medical equipment and I didn't need a degree in physics to do it. This one made me laugh .
( ME: ) IT REMINDS OF OBAMA WHEN HE SAID HE HAD BEEN TO ALL 57 STATES AND THERE WAS ONE MORE TO GO ?


ANYWAY:


( ME: ) But At least the CAT scan technology was developed by physicist I can't remember his name anymore. I would tell you what medical device you should have referenced for the analogy but you need to find that out for yourself, being a physicist and all you should have no problem with it.


( OutLaw ): He is at best dragging the resonant frequency down 30 or 40 channels due to his body adding capacitive loading to the antenna, but it is already two or three times below the middle of his frequency range anyway.


( Me ): All you just said is that touching the coil "de-tunned it" Oh and by the way if the shield on the coax were open you could still see the same kind of response touching the coil IE. THE COAX COULD STILL HAVE BEEN A PROBLEM Not saying it was just saying it could have been..


He can only calibrate somewhere within the 40 channels of the radio. Meaning while he could alter the resonant frequency from capacitive loading, only downwards and he is already thrice downwards in resonant frequency to begin with.


( OutLaw ): Therefore the meter will not show a much lower SWR from his capacitive loading, it is mainly caused by a shift in reflected power. Only makes sense if one considers the definition of lower SWR is less reflected power.


(ME) You can't have it both ways. If indeed there is less reflected power from touching the Coil then as far as the radio is concerned it is happy with the impedance load it sees and cares nothing about the frequency or channel shift or bla bla bla My GOD man !!


(OutLaw) However the bulk of the 'less reflected power' is due mainly to dissipation.
(ME: Again the radio wants to see a 50 Ohm impedance. If adding capacitance to the coil when you touch it does that it could care less about resonate frequency as long as it sees a good match "IE. IMPEDANCE" the radio will try to deliver all it's power or RF to whatever that load is. In this case it's the coil with a hand wrapped around it, it could just as easily be 50 OHM resistor but in this case of course the coil will have to dissipate that RF mostly in form of Heat. ) This leaves only energy dissipation to explain the drop.


( Outlaw ) This dissipation effect will be greatest at a nodal point of voltage along the length of the antenna. HuH,What???


( ME ) (NO NO NO If the Load coil is the point of good impedance match little power will be feed to the element or "stinger" it will be mostly trapped "SHUNTED " in the Inductor. If what you say is true you would just put a dummy load on the radio and attach any length stinger or wire you want to the point where the 50 ohm resistor is soldered to the center pin of the PL259 and magically all the rf would be transferred to that random wire.


(( OutLaw) Since you are bold enough to state I am wrong in my analysis while using invalid science to back you up I think I am justified in setting you straight.)


(ME When you put your hand on the coil you are causing it to be de-tunnedat a different Q Factor it has little to do with shunting all the RF through you Body and everything to do with becoming detuned
(Then YOU said): He is at best dragging the resonant frequency (IE. DETUNNING SAME THING I SAID BEING SAID DIFFERENTLY ) down 30 or 40 channels due to his body adding capacitive loading to the antenna


Just to be nice I will give you a way to prove energy dissipation effects from what he was doing. ( ME: THIS ISN'T WHERE YOU SHOULD BE GOING, BUT GO AHEAD) Have someone repeat exactly his circumstances and actions while you are 20 feet away holding a field strength meter very still. You will see the drop in radiated field intensity. Not magic, science.


(WOW! WHEN YOU DECIDE TO BE WRONG YOU DON'T LET THE FACTS GET IN YOUR WAY. )
(FIRST OFF YOUR LITTLE BE NICE TEST IS USELESS)
"At least not in the context you are trying to use it, it does prove something but not what you are trying to prove!"
(ME: ) AND HERE IS WHY. WE HAVE ALREADY ESTABLISHED THE FACT THAT WHEN HIS HAND IS WRAPPED AROUND THE COIL IT INSTANTLY TURNS THAT POINT IN THE ANTENNA CIRCUIT INTO "Your words a :: shunt " ALTHOUGH YOU WERE CORRECT WITHOUT KNOWING WHY YOU WERE, A SHUNT IS AS FOLLOWS.
A low-resistance connection between two points in an electric circuit that forms an alternative path for a portion of the current. Also called bypass.


(ME: ) SINCE THIS IS THE CASE YOU CAN'T USE YOUR TEST BECAUSE EVEN IF THE ANTENNA WERE 20 to 1 WITHOUT YOUR HAND ON THE COIL, IT WOULD SHOW MORE FIELD STRENGTH THAN WHEN YOU WRAP YOUR HAND AROUND THE COIL CAUSING SOME OF THE RF TO BE SHUNTED "WITHIN" THE COIL.. YOU CAN'T HAVE IT ANYWAY YOU WANT IT.... I GUESS IT HAS SOMETHING TO DO WITH PHYSICS, HELL I DON'T KNOW ??


I'M SORRY I CAN'T TAKE ANYMORE OF THIS IT'S PRICELESS !!!!!!!!!!
I DON'T NEED A WEAPON YOU GAVE ME ALL THE AMMO I NEEDED!


Since he most likely just dropped the stinger in without tuning a new Wilson it is probably around 3 inches too long. As He is using a 40 channel radio, not an export or an analyzer where he can move down 150 channels, no matter where in the 40 channels he was when he calibrated the forward power the SWR is buried far outside of his ability to calibrate anywhere near the actual resonant frequency of the antenna.


( OutLaw: You Get some credit for this ) Since the reading he was seeing was based upon the forward calibration he did before he grabbed the antenna, the meter would see less RF returning. Therefore a reading of lower SWR based upon his previous power calibration reference.


Another proof is have a third person in the vehicle to recalibrate the forward power reference while he is holding the antenna in TX. While still holding it in exactly the same position next measure reflected. If your meter is of high accuracy you will see the change based only upon the resonant frequency drop caused by the capacitive body loading since both calibration and measurement was done under the same loaded condition. I don't recommend he have an amplifier on at the time of course. Around 25 volts P-P is plenty to hold onto, 200 P-P not so good.


This is 8th grade physics. I will say to you what I say to anyone. If you want to shoot me down always bring a loaded weapon.


#### I DROPPED OUT OF PHYSICS IN THE 7th GRADE, OH WELL.

 

I believe that no problem. A 'SHUNT' as you call it is a load, resistance turning RF energy into heat by increasing molecular vibration. Otherwise known as the correct term I used 'dissipation'. I will not waste any more time talking to a dense, uneducated wall. Have a good day.

 

Oh I'm having a great Day, Thank You. Wow! I think someone needs a Hug.

Ok lets see:

(Outlaw ) Called me a a dense, uneducated wall,,,,, Did you ever notice when someone can no longer defend there position they resort to name calling. But even more important he could not point out one thing that I had wrong.. Yes it's best you don't waste your time.

OH! Did you bother to find out what a CT Scanner is and how it works, I suppose not..

I think everyone will understand the basics. A shunt is exactly what I said it is
, A low-resistance connection between two points in an circuit that forms an alternative path for a portion of the current..

That means this if you shunt the output of CB transmitter to ground with a 50 Ohm resistor the RF Power that is delivered to that resistor will be dissipated in the form of heat. So dissipation is nothing more than a term used to describe what happens to the energy being applied to the SHUNT or if you rather a LOAD.

You should take youre own advice:If you want to shoot me down always bring a loaded weapon preferably loaded with FACTS. And leave the name calling in the school yard..

Oh and just for the record I was able to jump past 8 and 9 grade as my Grade point average made me eligible to enter a technical college. From 10 thru 12 I attended SUN AREA Technical College with perfect grade point average and still maintained a high grade level at High School as it was required to be allowed to attend Technical College. That is what I meant by dropping out of 7th grade, After graduation I qualified for a scholarship to another 3 year advanced technical degree a Williamsport Technical College that was a long time ago most likely before Outlaw was born. So call me what you will but I know the difference between CT Scanning and Magnetic Resonance Imaging or MRI.. Just for the Record!!

And that's all I have to say about that. THE END

 

A small amount of knowledge and one would understand the analogy, the flesh is not affected by magnetic fields nor does it significantly disturb them. Otherwise while in the field one would be stuck to the wall. Therefore his hand had no effect on the magnetic field from the coil which is what you implied. If you were born in the 40's then your 'long before' comment may have validity. However when I hired and fired people in a billion dollar R&D lab who came in with their Associate degrees from DeVry in the 80's, I learned the extent of their training based upon the hours I spent helping them. It means little. You could have avoided all of this by stating your opinions on page one without resorting to proclaiming to the public I did not know what I was talking about. This monumental waste of time caused by your lack of communication etiquette and form, i.e., the way you feel the need to point out your perceived flaws in another when you clearly are incorrect is abominable. These pointless time wasting thread hijacks are why I do not post here often. State your opinions, respect those of others, and all of this could be avoided.

 

( YOU SAY ) A small amount of knowledge and one would understand the analogy, the flesh is not affected by magnetic fields nor does it significantly disturb them. Otherwise while in the field one would be stuck to the wall. Therefore his hand had no effect on the magnetic field from the coil which is what you implied

I don't disagree with this one instance and I will even give you the benefit of the doubt that you had a brain fart when you used CT Scanning in the analogy certainly someone that claims they ran a Billion Dollar R&D Lab should know the difference between CAT Scanner and a MRI. Scanner. I do and most do. Agreed it got out hand for that I'm Sorry.

As far as I'm concerned this is over..

 

Yes I meant MRI not CAT which should have been obvious from the reference to strong magnetic fields. So what. Instead of deflecting the issue and refusing to answer the point of contention try staying on topic. The topic was you calling my explanation about the effect his body has on the antenna incorrect. You do not 'win' by pointing out my forgetfulness of medical terminology since I never go in for medical care and never will, the point was about the fields around the antenna. By the way the R&D lab was concerned with reverse engineering the technology of other nations, not building medical equipment. So you cannot make conclusions based upon this. No hospital uses Xray lasers to destroy incoming nuclear missiles nor EMP weapons involving mega-gauss fields. Yet CAT scan is the single point you can find to attack. Waste of time.