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looks great .if he starts making these and selling them i,ll have to get me one .hows the swr on it ?bandwidth?

he wont maybe he'll tell you how to make one yourself but i dont think you will ever see the shockwave vector 4000 at copper.com

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one could always homebrew a copy if they had the measurements ..... and confidence to try .

Aluminum Tubing Type 6063 - 6 ft.

mmmmmmmmmm..........................
might be time to start asking/learning about gamma matches . blame bob , shock and W5LZ , LOL
are there any other omni cb antennas besides the vector and its copies and the wolf .64 antenna that use a gamma match for tuning ? what's the benefits of one over the other ? any difference it tuning ability ? tx db gain ? noise floor ? ears ?
W5LZ if i paint it pink will it make the modulation louder ?
Wolf Radio.com CB, Ham, Pirate Radio Antennas [CB Antenna]
so a gamma is just a rod that can have its length adjusted going up and down the radiator vs. a coil or ring circuling below the bottom of the antenna and being taped for resonance ?

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well im not a antenna designer by any means but i would
think a gamma tuning would have less loss than a coil and probaly the
same if not slightly better than a tuning ring.personally i like to see it
in 50 or higher mph winds.and 1 inch thick ice on it.up here in p.a
a strong antenna is a must.the I10k is outta my price range

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For those that were wondering what my measurements on this antenna are......Here you go. The vertical whip is 29 feet 7 and 1/4 inches long from the bottom of the connector bracket to the tip of the whip. The four radial arms are 81 and 1/2 inches long from end to end. The loop is 129 inches in circumference. The gamma is simply adjusted for lowest VSWR. Sorry I did not measure the gamma and I did use a home made Teflon gamma match with a weatherproof HN connector.

You may notice this last version of the antenna is more sturdy. I used the parts from two Vector 4000 antennas so that I could double up the lower sections and cut the flimsy top sections off. The four black plastic arms that hold the radials in place are also taken from two antennas. The ends were cut and then two pieces were screwed together with 4-40 hardware to make them longer.

The antenna was tuned on 11 meters and still provides under 2:1 VSWR on 10 meter SSB. The gain and bandwidth with the larger loop seems better to me and certainly exceeds what is possible with a 5/8 wave. The main advantage of the gamma match versus a coil with a tap is that a gamma allows you to tune out both capacitive reactance and inductive reactance. The coil only allows you to adjust the inductive component.

Hey Shockwave, I thought a gamma can only tune to a capacitive type load and thus the gamma has a smaller spectrum for use as compared to a series inductive type coil used for matching?

Hello Marconi,

The gamma match is a variable capacitor that also forms a variable inductor. By sliding the gamma rod in or out of the gamma tube you are changing the capacitance. By sliding the gamma bracket up or down the driven element where it attaches to the gamma rod, you are changing the inductance.

One experiment I've conducted used a gamma match on a driven element and was able to tune the element for flat VSWR while adjusting the length of the driven element all the way from 1/2 wave to 5/4 wave. The gamma had much more tuning range then I originally expected and seemed to be able to tune almost any length radiator.

The one exception where the gamma could fail to give a match would be if the driven element were significantly shorter then what would be required for resonance. To add electrical length to the antenna we slide the gamma bracket more towards the grounded part of the driven element. At some point this stops looking like adding more radiator length to RF and starts to look like a short circuit.

Generally speaking when an antenna is too short to resonate, we add inductance to the matching network in order to cancel out capacitive reactance. When the antenna is too long, we add capacitance to cancel out inductive reactance. The gamma can do both however, it has limitations when the antenna is too short.

Thanks for your remarks Shockwave. I re-read my post and I think I was confused in my argument and maybe got things backwards. I am trying to get back to posting, but I'm still recuperating from a recent 7 days in ICU flat on my back. I'm very weak and my thinking is not clear enough yet for detail discussions.

Right now I’m staying with my daughter until I get my strength back. I had a bout with Aluminum oxide inhalation poisoning that resulted in pneumonia. During the stress with my lungs being inflamed, my heart went A-Fib and my condition was all complicated with my diabetes as well.

A caution to everyone, be careful and work cleaning your aluminum antennas---in a well ventilated area only.

Giving this project a little thought, I believe I can use the ground hub of my other Penetrator base for holding the cone arms and make a Gamma match. What's the chance you could post the measurements of the Gamma?

Is the main radiator insulated from ground at the bottom or DC to ground & the radial arms?

OK, so how does it perform? And against what and how did you measure?

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