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Best Moblie Antenna for OTR Truck
- Thread starter ctvanover
- Start date
Copy paste it from thoses sites where it says that.
Again, All you are doing is memorizing what you read and your lacking at that. You have no concept of what it means or the theory behind it. If you did know, you wouldn't be using a matching transformer device on your CB antenna because you really don't know what it does or what it is really used for. Your only reason is the "WOW" factor.
I explained it to you what they are used for and why and it's right in line to what you will read on K0BG and to some extent on G3STO site also.
What you missed on G3STO's site is it's really a site for using an auto-tuner for multi-band HF mobile operations on a single antenna. Using ATU's is not ideal for mobile ops. Reason is because ATU's don't match up well to low impedance's which is common for shortened HF mobile antennas because he is still having to use some matching at the antenna feed point along with a loading coil. ATU's don't change the tuning on the antenna itself just as his site says and nearly all of us in this forum knows already. He can save all that trouble and go with a screwdriver antenna or go with a remote ATU mounted right at the antenna feed point then the ATU becomes part of the antenna system as a matching device. Apparently he never thought of that.
That site has nothing to do whatsoever about running a loaded CB antenna already reasonably matched up to tune on the CB band and all that information given has no bearing on what your running in your mobile CB station. Again, if you are using a loaded CB antenna for the CB band, you do not need any other matching. If so, you have other problems to figure out why you think you do.
You are entitled to your opinion but when you try to give it out as facts, you are being ignorant here. 30 years of driving trucks means nothing as to being knowledgeable about things either because I have over 31 years myself logging over 4 million miles and it wasn't all done being a steering wheel holder driving 400 miles a day from terminal to motel and back.
If you are so interested in radio operations and theories behind it, I would suggest you get your General class Amateur radio license and step into a whole new world of radio that you may find more satisfying and rewarding and you will learn a lot more than being just on the CB band. These are relatively easy to get these days and I suggest research and study the information as opposed to memorizing the answers.
No where at all does it say resonant antennas on mobiles are at those low impedance's you specify.
Again, All you are doing is memorizing what you read and your lacking at that. You have no concept of what it means or the theory behind it. If you did know, you wouldn't be using a matching transformer device on your CB antenna because you really don't know what it does or what it is really used for. Your only reason is the "WOW" factor.
I explained it to you what they are used for and why and it's right in line to what you will read on K0BG and to some extent on G3STO site also.
What you missed on G3STO's site is it's really a site for using an auto-tuner for multi-band HF mobile operations on a single antenna. Using ATU's is not ideal for mobile ops. Reason is because ATU's don't match up well to low impedance's which is common for shortened HF mobile antennas because he is still having to use some matching at the antenna feed point along with a loading coil. ATU's don't change the tuning on the antenna itself just as his site says and nearly all of us in this forum knows already. He can save all that trouble and go with a screwdriver antenna or go with a remote ATU mounted right at the antenna feed point then the ATU becomes part of the antenna system as a matching device. Apparently he never thought of that.
That site has nothing to do whatsoever about running a loaded CB antenna already reasonably matched up to tune on the CB band and all that information given has no bearing on what your running in your mobile CB station. Again, if you are using a loaded CB antenna for the CB band, you do not need any other matching. If so, you have other problems to figure out why you think you do.
You are entitled to your opinion but when you try to give it out as facts, you are being ignorant here. 30 years of driving trucks means nothing as to being knowledgeable about things either because I have over 31 years myself logging over 4 million miles and it wasn't all done being a steering wheel holder driving 400 miles a day from terminal to motel and back.
If you are so interested in radio operations and theories behind it, I would suggest you get your General class Amateur radio license and step into a whole new world of radio that you may find more satisfying and rewarding and you will learn a lot more than being just on the CB band. These are relatively easy to get these days and I suggest research and study the information as opposed to memorizing the answers.
G3STO
. Most amateurs have become used to tuning for a minimum indicated SWR. This is meaningless in a mobile installation. WHY? An efficient mobile whip is unlikely to be 50 ohms. An inefficient one may be! Minimum SWR is NOT an indication of maximum radiation; it simply means the tuning device has found a point where it thinks the antenna exhibits 50 ohms but, to achieve this the voltage and current will not have the correct phase relationship for optimum radiation.
K0BG
Matching a mobile antenna to the requisite 50 ohms is a requirement for several reasons. For example, modern solid state radios are designed to reduce their output power when the input SWR reaches ≈2:1. Some will handle a little more, some a little less. Once matched, the SWR doesn't have to be flat, so anything below 1.6:1 is close enough. Remember too, if the unmatched input impedance of your antenna, is less than 1.6:1 at resonance, you need a better antenna and/or mounting scenario.
Ok here it is...... Maybe if you read the 2 paragraphs above several times you will get it.
PLEASE NOTE , k0bg last sentence UNMATCHED impedance.
Also less than 1.6 at resonance YOU NEED A BETTER ANTENNA AND/OR MOUNTING SCENARIO.
Read it like this if No Matching is needed then you have a ineffiecient antenna.
When a antenna is tuned for resonance , It will have input impedance of 18 to 36 ohms . This is when maximum FS radiation occurs. For the radio to put out full power it has to
be matched of some type to see 50 ohms , which i know you realize most hf rigs cut back when the swr is above 2.1 . This is why you need matching.
So there is no sense in a rock throwing contest. It's called childs play. We both have the right to believe what we wish.
Anyone that is interested in Maximum Power radiated. Then i assure you , The best method is tuning for maximum FS via matching at the antenna feedpoint. Give it a try that is what the hobby is all about , It is how we all learn . Trial and error.
Thanks Tony 73
Nowhere does it say that. Also you are applying principles used for matching multiple Amateur bands on frequencies well below the CB band that don't apply to you and your CB antenna.
Every mobile antenna and every install is unique. All those numbers given are guidelines. If you owned your own analyzer and took measurements you would see this for yourself and why I keep saying you don't need matching on your CB antenna.
An Analyzer can show where the resonance is on a given antenna and it can very well be 50 ohms and a near flat SWR with the reactance value at 0 representing where the inductive and resistive reactances are equal, then you're at the resonant point.
K0BG matches his antennas at 40 ohms on 40 meters for a reason, so he can compromise between all the HF amateur bands above and below that to get a good tuning.
This is the whole point you don't still get, all these guys are showing is how to get good tunings for multiple bands on 1 antenna. One guy uses a ATU in line which most people wouldn't bother with while the other uses shunt coils or other forms of inductive matching.
Your CB antenna with that matching unit is actually increasing the impedance not lowering like you may think it is. An Analyzer would show that.
I'm not going to keep repeating myself here anymore, hopefully one day you will get it.
Taking a snippet that looks good and ignoring the larger context being discussed isn't the way to go about this. The K0BG paragraph, including the context it was presented in by the original author, is not disagreeing with fourstringburn.
The other one, well, the fact you hold that information in such high regard is more a reflection on what you know than anything. I can offer a good reading suggestion that will help correct your views on said page. Some things he gets wrong, and others he is right for the wrong reasons. Also, I have yet to see you actually use his correct call sign, just so you know. While I don't personally care (I found his site easily enough, seen it before), some may choose to read into that.
You seem to have come across a lot of details, but at the same time clearly don't understand the implications and applications of many of the details you know. Throwing them out without understanding them says a lot about you to many people who frequent these forums.
And finally, trial and error, in and of itself, will only take you so far, true understanding is found elsewhere. At least you seem to be working towards said understanding. Don't give up, but be more picky about your information sources, and don't forget the context.
The DB
Many people think this way... That being said, one specific question in it caught my attention.
Can and have multiple times at multiple locations. Field day, five different locations in five years, same antennas, reproduced results, at least as far as can be with the changing nature of the ionosphere, which is something we don't have control over when setting up and tuning said antennas. This is just one example.
This is a highly technical forum, to the point that we have actual broadcast engineers here. Are you going to presume that said broadcast engineers also rely on something like luck? I can assure you that that isn't the case. Just because a few hobbyist's rely on luck does not mean that everyone relies on luck. The more knowledge you have the less you need to rely on such pointless and unreliable things. If you have an antenna that isn't working well, you can choose to follow W4ZT's idea and hope for luck, or you can talk to people here and actually get an explanation and workable solution.
I sure hope this isn't directed at me, if it is then you clearly haven't done your homework...
This document borrows heavily from several sources, at some points word for word, and there is no citation of said sources. It is like the guy is claiming this as his own work when most of it was taken from others, especially one M. Walter Maxwell, who's works were outright plagiarized in the writing of this document. And when it comes to said sources, especially the main source when it comes to SWR and complex impedance, I have quoted his works multiple times on this forum. You can get most of this from the original sources including a freely available .pdf file called "Another Look at Reflections".
Also, some of the information in this document directly contradicts things written by one of your earlier sources, one which you said was "spot on", so which source is correct? Referencing random documents that sound like they agree with you at first glance isn't working out well for you.
Finally, if you actually understood this material, you would be able to explain it, then use sources as a reference. You, however, are trying to use the source as your explanation, which has a very different result. With what you are posting along with it, you also clearly don't understand the sources you are using as well as you think you do.
I'm not saying to stop using them, I am simply saying that you should research them more and ask questions about them. A source should not be relied upon for information, it is better that you can explain whatever you are talking about yourself, a source should be little more than a confirmation of what you are saying.
The DB
As mentioned earlier it is g3tso... sorry.
You have a misquote. No where does his site advocate an auto antenna tuner !
Auto tuners work on SWR so are not very good at matching antennas ! Base loaded screwdriver antennas are very ineffiecient !
Quite right, but those with practical experience will know that good antennas are !
Very interesting, K4poz a retired Chief broadcast engineer told me the exact same thing g3tso site states. Tune for maximum FS then use a matcher at the antenna feedpoint. The is the Best Method.
Its like the Met Men who claim the Jet Stream runs the weather, utter garbage !
It is best that i NOT get into these debates, I have found what works.
Tony 73
Here he says:
Once the antenna has been resonated at the operating frequency, an ATU can then be used as an Impedance Transformer.
That's true but it would be better suited to be mounted at the antenna feed point.
Duh! I already said that along with the fact nearly everyone on this forum know this.
Screwdriver antennas aren't really base loaded antennas. I use a capacity hat so do lots of others which is top loading the antenna which increases radiation efficiency, increases bandwidth, and raises RF currents to the top of the antenna.
You have none except putting something on your CB antenna and judging it by the "WOW" factor! Again you read Ham radio mobile information which is for running multiple bands on single antennas and apply it to your mono band CB antenna. Hey it must good work since Hams use it!
That guy is ignorant if he told you that for use on your coil loaded CB antenna to run on the CB band. Once Again...you have a coil loaded antenna already designed for the CB band that may only require fine tuning with either an adjustable whip or thumbscrew or whatever tuning design it has already. You do not need or will benefit from a matching device unless your antenna is so poorly designed where it can't even come close to a reasonable tune.
If you were to invest in an antenna analyzer and learn how to use it and what all the values mean, you might just learn something on your own and apply it to your specific mobile operation and just maybe, you might realize what I'm trying to tell you!
I think your day cab truck has exhausts leaks in it and you may be slowly suffering brain asphyxiation from it.
Agreed, at least until you have a basic idea of what is going on. Going by what others tell you is not the same as understanding, and in a discussion/debate with someone who does you simply don't have what it takes to hold your own.
As long as you are talking about a single, or a very narrow bandwidth of frequencies, referring specifically to an antenna that is a shortened 1/4 wavelength antenna, and feeding said antenna with coax, you are very close to being correct, however, there is a more efficient way then even that... The answer is also right in the pages of at least one of your own sources, so I'll leave it to you to find on your own, or not.
Edit: Actually, fourstringburn actually mentioned what I was referring to here in the post just above this one. I wasn't referring to the specific device, more where it was located. That being said, I would take that device as a correct answer here just as well. /Edit
Actually, if you have an antenna that doesn't require matching, such as a 1/4 wavelength CB antenna, you can get even more efficient as all forms of matching have some amount of loss, but your misunderstanding of sources is causing you to believe that such a thing cannot exist... You have posted as much multiple times above.
A lot more "works" than you seem to realize. The circumstances you are working with on the CB band are very similar to what many commercial engineers work with, a single, or very narrow range of frequencies, and antennas that, even when shortened, are a significant length of the full 1/4 wavelength or longer. As long as you stay in that region you will be fine, even if you don't really know why. Venture beyond, for instance, an antenna that has to work from 1.8 MHz to 30 MHz or even only a significant portion thereof, with your knowledge you will either have to have at least one antenna per band (some bands in question are much wider than the CB band), or you need to use a different method to access said frequencies. This requires knowledge that is right at your fingertips in your own sources, yet beyond you.
Not all antennas are the same, or have to meet the same requirements. To assume that one setup will be the best setup for everyone everywhere is only limiting yourself before you ever begin.
Expecting people to fall in line with what you say because "that is what a broadcast engineer told me", or "that is what this link I am referring to says" isn't how to get a point across. Demonstrating that you don't understand your own links is only making your situation worse.
But this is a free country, you are free to believe as you see fit, just don't be surprised when someone who knows better challenges you on it when you spout it as fact.
I've told you twice before, I want you to learn about antennas. I still want you to learn, it will only help you, and perhaps even give you the tools to properly help others as well. The more people we have with actual knowledge, the better everyone in the hobby is. However, I (we) can only point you in the right direction, the rest you have to do yourself.
Edit: Hey fourstringburn, whats this with us liking each other's posts after out last few "discussions"? The world is a funny place sometimes, is it not?
The DB
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Yes, funny place indeed! I really like your last one posted here even though it will probably do no good.