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Modified Vector 4000

bob85

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Mar 30, 2005
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stock vector 4000

StockVector.jpg



here is the first pic of shockwaves prototype wideangle vector 4000, he has not adjusted it for best signal strength at distance or installed the upgraded connector so it will look a little different when it is finalised,

if he manages to extract more signal at distance than the stock optimised vector you are looking at the best performing single element vertical ever constructed for 11/10mtrs (y)

Increasedangle.jpg
 
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stock vector 4000

StockVector.jpg



here is the first pic of shockwaves prototype wideangle vector 4000, he has not adjusted it for best signal strength at distance or installed the upgraded connector so it will look a little different when it is finalised,

if he manages to extract more signal at distance than the stock optimised vector you are looking at the best performing single element vertical ever constructed for 11/10mtrs (y)

Increasedangle.jpg
I'll take 2 bob.
 
i hope once youve got it tweaked for peak performance that youre willing to share all the meterials descriptions and final tuned lengths . freecell suggested in his comments about it that he felt going to a 3/4 or even a 7/8 inch main radiator could lead to a better pattern than the origional avanti . sirio basically did that with their LW-150 being 31 feet tall , but its only suited to fair weather areas according to everyones comments ive read on it . shockvave , your ground radial length and angle and of course the loop length are different and could noticably affect things better or worse .....

looking forward to more about it ;)
 
im sure he will, i have the measurements shockwave ended up with,
heres a pic of his modified vector4000 installed and tuned for best signal at distance.

ModifiedVector-1.jpg
 
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 ?
 
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
 
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.
 
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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?
 

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