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Not much of an antenna per Cebik
I read a comment attributed to Cebik where he stated that any
antenna that is not 1/4, 5/8, 1/2 or 1 wave length is not much of an antenna ! This is a false statement especially when one considers an antenna element based on 1 WL. This antenna is widely used and well described in all antenna books. I have modelled a similar arrangement in Gaussian form where the elements are bent into a Vee shaped like yagi with elements extremely close together where it provides exceptional gain and pattern and can be related visually to a bent long boom but without elements. A planar antenna can also be made with a similar length of radiator with a variable resonator that makes it applicable to a continuous10 thru 20 antenna wherein the resonator serves as a radiating portion instead of the normal coax stub. Also ideal for S.W. listeners on intervening frequencies.( See Cecil's antenna page which uses variable stub lengths instead of a variable resonator) Seems like a lot of mis information is being given out with respect to antennas apparently with the silent agreement of perceived antenna experts and where caustic opinions out weigh technical content . Regards Art |
Not much of an antenna per Cebik
"art" wrote in message oups.com... I read a comment attributed to Cebik where he stated that any antenna that is not 1/4, 5/8, 1/2 or 1 wave length is not much of an antenna ! This is a false statement especially when one considers an antenna Art, why is it that you make statement like this and never give a reference to where you got it? |
Not much of an antenna per Cebik
On 30 May, 09:27, "Jimmie D" wrote:
"art" wrote in message oups.com... I read a comment attributed to Cebik where he stated that any antenna that is not 1/4, 5/8, 1/2 or 1 wave length is not much of an antenna ! This is a false statement especially when one considers an antenna Art, why is it that you make statement like this and never give a reference to where you got it? Why is it that you also continually do what you do? I read it on E ham which is why why I used the word "atributed" You can always read up on Cebik's pages but what is important to you, the relevant antenna facts or who to point your finger at? Art |
Not much of an antenna per Cebik
art wrote:
On 30 May, 09:27, "Jimmie D" wrote: "art" wrote in message groups.com... I read a comment attributed to Cebik where he stated that any antenna that is not 1/4, 5/8, 1/2 or 1 wave length is not much of an antenna ! This is a false statement especially when one considers an antenna Art, why is it that you make statement like this and never give a reference to where you got it? Why is it that you also continually do what you do? I read it on E ham which is why why I used the word "atributed" You can always read up on Cebik's pages but what is important to you, the relevant antenna facts or who to point your finger at? Art E-ham is a pretty big site. Can you direct us to where you read it please? Irv VE6BP |
Not much of an antenna per Cebik
On 30 May, 11:17, Irv Finkleman wrote:
art wrote: On 30 May, 09:27, "Jimmie D" wrote: "art" wrote in message groups.com... I read a comment attributed to Cebik where he stated that any antenna that is not 1/4, 5/8, 1/2 or 1 wave length is not much of an antenna ! This is a false statement especially when one considers an antenna Art, why is it that you make statement like this and never give a reference to where you got it? Why is it that you also continually do what you do? I read it on E ham which is why why I used the word "atributed" You can always read up on Cebik's pages but what is important to you, the relevant antenna facts or who to point your finger at? Art E-ham is a pretty big site. Can you direct us to where you read it please? Irv VE6BP- Hide quoted text - - Show quoted text - Irv, I remember reading the article "Dipole or Tripole" plus the readers follow up comments but that is all I will have to go back and research for the comment again. You used the word "please" which is not typical of this group so I will get right on it tonight and get back to you. I had a quick hunt just now and came across a discussion as to why the word "Pole" does not belong when talking about antennas. I got in to great difficulty with that term in my earlier years because physics constantly refers to dipoles as "Dipole" irrespective of size ( Di = 2, pole equales electrical poles") I got into trouble again on this newsgroup again with re4spect to the use of that term from a couple of posters. Sometimes it seems that you just cannot win! Very best regards Art |
Not much of an antenna per Cebik
On 30 May, 11:17, Irv Finkleman wrote:
art wrote: On 30 May, 09:27, "Jimmie D" wrote: "art" wrote in message groups.com... I read a comment attributed to Cebik where he stated that any antenna that is not 1/4, 5/8, 1/2 or 1 wave length is not much of an antenna ! This is a false statement especially when one considers an antenna Art, why is it that you make statement like this and never give a reference to where you got it? Why is it that you also continually do what you do? I read it on E ham which is why why I used the word "atributed" You can always read up on Cebik's pages but what is important to you, the relevant antenna facts or who to point your finger at? Art E-ham is a pretty big site. Can you direct us to where you read it please? Irv VE6BP- Hide quoted text - - Show quoted text - Irv, you are correct when you stated it was a big site! I spent a lot of time reading readers comments until my eyes glazed over. It was like reading every quabble from our own archives for the last twenty years. I think I will have to read the Cebik articles for myself and trace it down that way which will be much more educating. I am glad however that I used the word "atributed" rather than stating it as a fact. I will continue with this progect Regards Art |
Not much of an antenna per Cebik
Art wrote:
"I have modelled a similar arrangement in Gaussian form where the elements are bent into a Vee shaped like Yagi with elements extremely close together where it provides exceptional gain and pattern and can be related visually to a bent long boom but without elements." There is a TV antenna something like that on a rooftop within 2 blocks from here. IIt must have some exceptional characteristic. Someone built it. The elements are short compared to several wavelengths at 200 MHz. Does the model result in a low deivepoint impedance? Does the Vee result in high response off the tips of the elements? Does close coupling between elements result in great bandwidrh for the antenna? Best regards, Richard Harrison, KB5WZI |
Not much of an antenna per Cebik
On 30 May, 19:41, (Richard Harrison) wrote:
Art wrote: "I have modelled a similar arrangement in Gaussian form where the elements are bent into a Vee shaped like Yagi with elements extremely close together where it provides exceptional gain and pattern and can be related visually to a bent long boom but without elements." There is a TV antenna something like that on a rooftop within 2 blocks from here. IIt must have some exceptional characteristic. Someone built it. The elements are short compared to several wavelengths at 200 MHz. Does the model result in a low deivepoint impedance? No, as I remember it was of high impedance Does the Vee result in high response off the tips of the elements? That is out of my realm in knowledge since I do not know how one measures that with ccommonly known units that is accepted in the trade Does close coupling between elements result in great bandwidrh for the antenna? Yes it did but you are thinking in terms of a yagi where element spacing is a dominant factor for the focussing effect. That is certainly not the case for a gaussian antenna where spacing is not the dominant factor because of equilibrium demands. Thus spacings can be very close as long as the current flow direction in both radiators are in concert with each other i.e. in equilibrium. As I have previously said the Gaussian aproach gives a constant gain which is in concert with other data desirables which does not require compromises to be sort. The ARRL antenna book have a chapter devoted to this problem where three antenna designs are created for desirables and the final design that with compromises was the best that one could attain. This is always the problem with yagi designs in that some covet certain desirables where others contend they are not important. That's life. The vee shaped length was 1.5 WL where the center current curve is manipulated for best results. In a way it is like an extended Zepp with respect to current pattern and the radiation pattern is similar to a long boom yagi. For a normal Gaussian antenna the max gain is equivalent to less than 20 feet with three elements( 20 M ant ) and does not increasein length or gain regardless of how many elements are added in search of gain where as the yagi can be of infinite length in the search of gain at the expense of beam width. The Gaussian by the way pretty much maintains a 65 degree beam width tho with extra ordinary methods such as the vee design it can reduce to half of that. Why I do not know. Regards Art Best regards, Richard Harrison, KB5WZI |
Not much of an antenna per Cebik
art wrote:
On 30 May, 11:17, Irv Finkleman wrote: art wrote: On 30 May, 09:27, "Jimmie D" wrote: "art" wrote in message legroups.com... I read a comment attributed to Cebik where he stated that any antenna that is not 1/4, 5/8, 1/2 or 1 wave length is not much of an antenna ! This is a false statement especially when one considers an antenna Art, why is it that you make statement like this and never give a reference to where you got it? Why is it that you also continually do what you do? I read it on E ham which is why why I used the word "atributed" You can always read up on Cebik's pages but what is important to you, the relevant antenna facts or who to point your finger at? Art E-ham is a pretty big site. Can you direct us to where you read it please? Irv VE6BP- Hide quoted text - - Show quoted text - Irv, you are correct when you stated it was a big site! I spent a lot of time reading readers comments until my eyes glazed over. It was like reading every quabble from our own archives for the last twenty years. I think I will have to read the Cebik articles for myself and trace it down that way which will be much more educating. I am glad however that I used the word "atributed" rather than stating it as a fact. I will continue with this progect Regards Art OK Art - Thanks for taking the trouble. Hopefully you'll find it, and next time rememer to note the source -- even if you are just attributing a statement. To those reading it, or at least myself, an attribution is as good as a fact when you are trying to learn. When we find out who attributed that statement to Cebik (who I hold in high regard), we can perhaps learn where he got the information, or how he got misinformed if such is the case. Irv VE6BP |
Not much of an antenna per Cebik
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