Sidebar Sidebar
  • You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
  • Click here to find out how to win free radios from Retevis!

best 11meter vertical ever, period.

the gm was put on the same short pole i had my i10k on for a quick test, i can't put it up at 2 wavelengths like i had at home,
if the gm was the equal of the i10k at the height i now use my antennas i would be using one,

im not using the hybrid because i got fed up of fixing the sirio parts of it,
i have 4 vectors all broke in one way or another, if it won't survive 100mph+ winds its no good to me,
i bought tube and all marine grade stainless hardware to mod my sigma but i don't have much interest in radio at the moment, its fishing and metal detecting season;).
 
bob85 said:
the gm was put on the same short pole i had my i10k on for a quick test, i can't put it up at 2 wavelengths like i had at home,
if the gm was the equal of the i10k at the height i now use my antennas i would be using one,
Click to expand...

I'm sorry I'm not understanding. You only tested it low and never tried it up as high as the i10k but your sure it isn't as good up high as the i10k or did I misunderstand? or is the i10k down low right now?
 
bob85 said:
32ft was too long, especially if the antenna is not close to the ground and does not use a skinny vector radiator, i used the vector basket on an extended avanti radiator, i have no idea if the new longer radial shorter radiator setup works better or not untill i try it,

booty, all i can tell you about my tap setting is that it was lower than the factory setting, been using the i10k for about 6 years without any problems and without been able to talk to stations i could on the vector hybrid,
read the early sigma posts on here to discover what i thought could be happening by altering the length, im still no wiser as to why we saw what we did but dozens of tests over 30 years against the best cb antennas available prove to me and locals that CEBIK and the patent were correct and the models are not, maybe its just my location skewing the results, the gainmaster can't equal the i10k where i use my antenna while others see the opposite :D
Click to expand...

Hey Bob, this sounds like deja vu all over again.

I, along with others have made the claim that the Gain Master does not seem to perform well when close to the Earth. In my case it didn't respond well until I got to 20' feet or higher. I'm not surprised that your I-10K does better if you're still, as I understand it, only raised up about 14' feet to the mount.

Here is an Eznec5 pattern overlay of what I see compared with these two modeled at 14' feet and at 40'. I did not test either at 14' feet in my real world experience here, but I agree your results are likely...if my height assumption for your station is correct. That's what I saw too, until I got my GM got up higher. For me, it's just another case of my models seeming to support what I see in real life, and now maybe your findings are also showing similar results in such a situation.

You will note in this overlay that the GM falls a little behind the I-10K when they are at 14', but is a little ahead at 40' feet. BTW, neither model is scaled to specs, and the lengths for the elements are just physical approximations of 22.5' feet for a 5/8 wave radiator.

View attachment I-10K vs, GM overlay.pdf
 
eddie,
the i10k is @18ft now and i have a small crankup mast that will get me up to about 1 wavelength,
i would be interested in trying a gainmaster again when i can put it higher,
for a white stick it did remarkably well, it would have to be modded like shockwave modded his to take more power.
 
I have a Sigma 4 and a Sigma 2. I tested them one at a time each at 30' and the Sigma 2 (Sigma 5/8 wave) was 2 s units over the sigma 4. I have owned 2 of these Sigma 4s and both of them were 2 s units below a 5/8 wave. YMMV but this antenna just didnt do it for me. So for now, the Sigma 4 is residing out back along the fence row.:tongue:
 
Zman said:
I have a Sigma 4 and a Sigma 2. I tested them one at a time each at 30' and the Sigma 2 (Sigma 5/8 wave) was 2 s units over the sigma 4. I have owned 2 of these Sigma 4s and both of them were 2 s units below a 5/8 wave. YMMV but this antenna just didnt do it for me. So for now, the Sigma 4 is residing out back along the fence row.:tongue:
Click to expand...

Hmmm...Pretty hard to accept your finding when you are probably one of the few who still own and use one of these. Your claims are a bit more exaggerated than the mfr's.

Hmmmmm.....Looks like a Super Penetrator 5/8 wave to me....

"...What a classic antenna the AV-170 Sigma II from Avanti was!!

Second only to the Avanti AV-174 Sigma IV, the Sigma II was a superb 5/8 wave base antenna.

Standing at 21 1/2 feet tall, with 4 x 9 foot long radials, this beauty would get you heard on Channel, and could handle 2000 Watts of power [apparently!]

With a gain of 5.14 dBi, this would make the signal about 1 'S' point stronger both on TX and RX, than when using a quarter wave antenna...."

5.14dbi is HARDLY one S-unit (1 S-unit = ~6db's) above just a 1/4 wave vertical antenna - let alone 2 S-units over the Sigmas IV - as you claim...

I don't doubt that you like it; but it seems a bit far-fetched to me . . .

http://4.bp.blogspot.com/_L341QXAi4...NVAh3g/s1600-h/Avanti+AV-170+Sigma+II+001.jpg
http://thecbmuseum.blogspot.com/2008/06/avanti-av-170-sigma-ii.html
 

Attachments

  • Avanti AV-170 Sigma II 001.jpg
    Avanti AV-170 Sigma II 001.jpg
    24.3 KB · Views: 118
Last edited:
2 s-units does seem like a lot . but several things could account for Zmans results . it may also simply be that the sigma 2 is better than the sigma 4 for his installation and location .

Zman , were both antennas installed in the exact same location and feed-point height ? was the same coax used for the comparisons also ? and were you comparing just local contacts , not skip ? im assuming the sigma 4 was properly assembled .....
 
aluminum antennas do not survive well under the ravages of severe thunderstorms, microbursts and winter storms, and i do not feel like lowering an antenna for every storm that blows through
 
BOOTY MONSTER said:
i always giggle at the folks that say it's as good as a 3 element beam . :whistle:
wtf did they do wrong installing the beam ? :headbang
Click to expand...


Greetings all:

I came across this the other day, so I'll throw it in, seems appropriate:

"Put a horizontally polarized antenna up more than a 1 wave length high to get a strong low angle radiation"

"A 3 element yagi max gain occurs with both parasitic elements spaced at 1/4 wl"

"An elevated ground plane vertical will be more effective for working DX than a dipole"

So my take away would be that if any of the above holds true then it is possible because as BM stated an improperly installed(i will also add designed) 3 element beam could simply be acting as a dipole...

good day

on edit:

I'm sure this may invite some discussion.
 
Last edited:

dxChat
Help Users
  • No one is chatting at the moment.


      Top Bottom
      Back