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Anyone tried the Sigma Venom Aluminum 5/8 from England?

One consideration is that aluminum tuber's will be more broadbanded @ lowest SWR than wire antennas and have at least slightly better receive. The wider the diameter of any radiator the more broadbanded it will be. Pretty much everyone review/claims by experience that aluminum tube antennas have better receive than wire-made ones.
 
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Rs , I have an original " Ar-10 " I got off the side of the road , it's short . I never measured it but guessing I think it might have been set-up for 10m ? I keep saying I'm going to fix it for 11m but never get around to it .:whistle::D Around here ( Ri ) the aluminum tubing is hard to come by . But then again I've only checked a few local hardware stores ! Someday I'll get it working ! I always like them " Back in the Day " .Also have whats left of & original Astro Plane after the wind got done w/it !:LOL: 73 , & God Bless , Leo
 
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I have a sigma 5/8 up now, this one doesn't have the radials. The thing work,s OK I don't think it works as good as the other 5/8 antennas I have had and yes it is a little thin on the tubing. I think I,ll have to replace it after the 1st hurricane. Also for a 5/8 it,s to short more like a 1/2 wave.
 
I have one sitting here. The weather is just getting nice here and winter is over. So hopefully I will be putting it up soon.

Low Boy, I want to model this New Sigma Venom 5/8 made with aluminum and I need some better dimensions, element lengths, tube diameters, and overlap (the black marks) in inches for the middle of US CB band...if possible. Could you help?

I like your image of a 55 Chev...I wish I still had my black 210 sedan delivery.

You can email me at edromans@comcast.net if it is better for you.
 
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Low Boy, I want to model this New Sigma Venom 5/8 made with aluminum and I need some better dimensions, element lengths, tube diameters, and overlap (the black marks) in inches for the middle of US CB band...if possible. Could you help?

I like your image of a 55 Chev...I wish I still had my black 210 sedan delivery.

You can email me at edromans@comcast.net if it is better for you.
Probably easist doing it thorough e mail or phone. I will e mail you.
 
Low boy , I have 2 friends that have them 1 still in the works after 50+ years ( finally in paint ) The other made like an Old School Gasser w/ a cross ram .The one still in the works we paid $50 for in the early 70's , 6 cyl , 3 on the tree . Drove it home , on the side it had the NBC Peacock & " Russ Fife's TV Repair " .
 
I hope these images show up OK.

In the lower right corner is my 55' sedan delivery. I didn't drive it on the streets at this time, I was drag racing running C Gas with a new dialed in 265", dual carbs, four speed, 411/456 Posi Trac gear, a Clay Smith cam, and running in the low 12's.

I married the girl in 62 and she is still my sweet heart.

Those were the good ole days.
 

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  • My Chev Sedan Delivery.pdf
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I'm with you 357, my Imax 2000 has been 70' in the air for 18 years now and has
survived numerous ice from freezing rain,two hurricanes,and many events of 60+ mph
winds.No need to replace it.
My IMAX has been up for over 20 plus years and I'm not going to replace it until it falls down. :)
 
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The Imax 2000 is 24ft long and is actually a 0.64 wave antenna. Its smaller sibling the A99 is a halfwave.

Hey MOGVZ.

I agree that making an Imax 0.024% longer to get to 0.64 wave length will likely result in a small increase in the gain. My Imax models shown below are all set at 268.5" x 0.125" inches for the wire radiator, It is fair that folks might disagree, but we are not talking about much difference here, and I don't believe this 0.64 issue is the big mystery we hear talked about.

At 268.5" inches the radiator wire on my model below shows 3.97 dbi @ 9* degrees. When I add 6.5" inches to the 268.5" the radiator = 275" inches. The model shows increased gain to 4.06 dbi at 9* degrees. So, there is improvement to be noted.

A while back some of the members had a discussion about the Imax having a capacitor in the center of the middle element. Click the link below. I think this is where the ideas form a Ham operator named Dave with a handle "Radio Daze" got us talking about this possible issue with the Imax.

http://radioaficion.com/cms/solarcon-i-max-2000/

IMO, this is probably the mystery we should be considering as to why the Imax performs as well as it does in the models I posted below. If my models are close to accurate...then here is a difference that matters...and IMO this is likely the real mystery.

Models

1. Control Center of Eznec showing the Average Gain results for the model below.

2. this model is a Free Space model with a 40pF capacitor in the middle section of an Imax with slanted down radials. Also included is a radiation pattern indicating the maximum gain and angle.

3. this is the same model as #2 and is over Real Earth. It also includes a feed line choke at a point level with the bottom of the ground plane radials. Also included is a radiation pattern indicating the maximum gain and angle.

4. this is the same model as #3 without the choke, primarily to show how the common mode currents ill-effect the pattern, and maximum gain and angle.

5. Control Center of Eznec showing Average Gain results of the model below.

6. this model is in Free Space without a 40pF capacitor in the middle of an Imax with slanted down radials.

7. this model is the same as #6. Also included is a radiation pattern indicating the maximum gain and angle which looks bad without the Imax capacitor in the middle sexton.

8. this model over Real Earth with no capacitor in the middle section. Included is a pattern showing the ill effects on maximum gain and angle.

At the end I included comparison overlays for the models over real Earth. Note: "wC40pF" vs. "nC40pF" in the titles for the models, meaning with a 40pF capacitor and without.

The (*) in front of the model listed indicates the active model results for maximum gain and angle on these overlays.
 

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  • Does the Imax have a capicator in the middle section..pdf
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