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Just put up I-Max 2000

Not bad... Any place on net that shows you actual construction from scratch be is base loaded, center loaded and top loaded base vertical construction as well as no coiling, just a straight up veritical and radials as well as multi poles vertically using same base and radials as well, be it solid coated wires inside of fiberglass poles for differnt bands? As well as how to directly dc ground out ones like Antron 99, the big stick, iMax ect without tuning rings just load inside the wire legnths you need and put it in the air.

I know radical but cutting wire to .64 wave to 5/8 wave to 1/2 wave and 1/4 wave, ambitious but seeking to see if can be done and use some of it to make it broad on some bands as well as cover as many as possible in one thing.
 
Marconi said:
The second model is also the same as #1, except I made the radial 2x the length. Compare these two models. If you will look close you will see that the longer radials have more current (red lines) flowing than the shorter radials in #1. To me this shows, among other things, these very long raised type radials are dominant over the radiator...and such results might not always be desirable.
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Click to expand...

To me having more current in the longer radials means more current in the radiator based on one of the laws of electrical energy transfer; that being that any current in the radiator is balanced by a corresponding current in the ground return ie. radials. Both currents have to equal and therefore more current in the radials (ground return path) must mean more current in the radiator and thus a stronger field strength. That's my take on it.
 
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Sorry HM, I don't quite understand your words here.
Captain Kilowatt said:
To me having more current in the longer radials means more current in the radiator based on one of the laws of electrical energy transfer; that being that any current in the radiator is balanced by a corresponding current in the ground return ie. radials. Both currents have to equal and therefore more current in the radials (ground return path) must mean more current in the radiator and thus a stronger field strength. That's my take on it.
Click to expand...

CK, as I understand this situation you would be the best voice to consider on this issue.

But, I see a lot more gross currents flowing on the longer 1/2 wave radials than the 1/4 wave radials, and almost no difference between the models for the currents flowing on the two radiators.

With the more balanced Starduster and the control model I posted above, I see the combined currents on the 3 or 4 radials are very similar to the currents that flow on the radiator, and for sure this shows results like you suggest CK.

I just don't see the same thing in the modified model with the 1/2 wavelength radials and this is why I made the claim that the radial current dominated the antenna pattern in this case.

Just for the record I post the Eznec Currents Logs for these two models posted above.
 

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  • Tabular Currents Log..pdf
    564.6 KB · Views: 4
Ok I am talking .64 5/8 1/2 1/4 wave antenna not radials at the moment , a multiband vertical somewhat like the iMax 2000 Antron 99 ect except with several wires as you go down the band 6 10 11 12 15 17 20 30 go from .64 down to 1/4
.64 --------- 1/4
6. ---------- 30
10 ----------- 20
11
12 - 15 -- 17 --

Kinda get it now hard to explain without drawing or verbally
 
Ok guys so far all is well but a few more questions

If I do as I have read between 18 feet to 21 feet 6" correct can it be with a solid center coax cable or stranded better? I want from what I read solid and do @ 19.5 feet or full 21 or would 18 be sufficient I am thinking of putting the bottom of the base up on a pole @40' I figure that is just a bit better than a wavelength give or take which band more towards 15-17-12 and a bit higher than that for most above 12 to 10, so far so good on this, and another question is about radials is it really necessary?
 
Okay also thought of replacing the top with a 108" Stainless Steel Whip, I know it will drop it more towards the lower bands and adding @ a 1.5 feet more to that. But not on the above mentioned on I have a second one I want to play around with also will it still retain the 5000 watt or will this drop it and any
Other ideas on modifying the top part, this is just for fun. I figure I can get it to be a 1-4 wave at @7.125 give or take a few kHz or two lol well maybe more lol.

Thanks guys
 
vkrules said:
Wont work. Your dealing with feedpoint variations from 25 ohm to over 1000 ohm The matching circuit in the imax is the problem. you would have to gut it and start again.
Click to expand...


Ok just wondering. What if multiple wire lengths inside fiberglass tubbing work connected to bottom so-239 and cut to particular resonant lengths?
 
wavrider said:
http://www.hamuniverse.com/n4jaantennabook.html

Heavy Metal you are asking a lot of questions.

Above link is a god read and may help you understand some of the theory behind antennas.
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I understand to a point it's putting it all
Together lol that makes me go grrrrrr lol... Especially
These
10/12 and 11 meter mobile antenna with the big air coils and how that goes vs winding ones in base center and top loaded. To make something like this drop just curious.... The thought was a tube of fiberglass or pvc and put solid coated wires in it cut to length for 5 6 7 bands and upto @50' and boost that 24' to 36 or 40' just playing around in my head.
 

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