Hi xforce,
Yes the "driven element"is the centre whip, IOW the bit that does the business.
The ground plane are the legs which "focus" the signal to the whip.
Achieving perfect "focus" aka resonance is what its all about, but as ever there are caveats..
The more legs, the better the "focus" but the legs have to be exactly right, as the leg numbers increase, the accuracy of spacing and cutting and angular positioning (ground plane shaping) becomes more critical or the "focus" goes off some place in the vicinity of the whip but not onto the whip sweet spot. As the legs increase the whips sweet spot has a tendency to get smaller.
When you get it just right..you know about it and no mistake !
It is a labour of love though !...I have been messing about with antennas this since I was 8 yrs old and count on one hand the number of times I have got it just right,as good as it could ever be first time.
I have ruined lots of my homebrew antennas by over tweaking, and rescued a few by tweaking ..such is life !
The cantenna,plantenna and spider are all formed based on the idea of focusing that incoming signal and really honing it to the whip which, in the large part, remains unchanged in its specification for each design.
Theoretically the 5/8 wave driven element should give more gain than 1/4 wave, so a 5/8 spider should outperform a 1/4 wave one but the margin would I suspect be very small.
Another caveat here is that 5/8 would jump right in the pool of the GSM brigade with big signals packed tight into the band so the improved gain may be nullified by the additional unwanted signal pickup.
You triangle one has the DNA of a double discone going on there...but in a slightly different way.
Maybe this is what you had an idea of in the final line of post #2564 on this page.
