...after wading thru all the muddy waters of overly long posts, condescension, ad hominem attacks & red herrings, it's plainly obvious, Homer, they have no answer to the real question they sidestepped of why 16 turns, other than the DB quoting the chapter in his one-off copy of The Bible Of Aesthetics on the ugliness of 5 Turns versus 16 Turns, and 4.25" vs 3" - lol
Oh, and don't forget how he brought in the irrelevancy of the center additional 1/8 wave of radiating surface which the 5/8 wave GainMaster has over the 1/2 wave GainMaster, as if that had anything at all to do with the subject matter at hand - that being the relevant similarities of both, each using a 16T choke at the voltage node.
I'll admit they almost had me questioning my Elmer whom, clear back in the '70s, said,
"Ya don't use a voltage choke at a current peak and ya don't use a current choke at a voltage peak", until I recalled why.
High impedance will choke current but not voltage, non-resonance blocks voltage from creating an efficient current radiator.
What do you find at the feed point of an end-fed 1/2 wave antenna? High impedance.
There's also going to be a matching network, but that's just to present a 50Ω input impedance for the transmitter & coax, but the antenna is still 1500Ω-2500Ω impedance at the fed end of the 1/2 wave antenna. It likes high impedance.
The 5T x 4.25' dia current choke provides around 5 KΩ impedance, according to the graph provided in post #223, whereas a 16T x 3" provides much less impedance, somewhere around only 500-750Ω, but happens to present a terrible resonance at the frequency in question, 1/3 wavelength.
16T x 3" is terrible for resonance, only poor to mediocre for providing high impedance.
Sirio aren't stupid, nor interested in minimizing. their profit margin, it's 16T (not an efficient 5T current choke) for a reason, and it's not to present high impedance to current at a voltage node, it's to present high non-resonance to the voltage at the voltage node in order to prevent the RF voltage from exciting radiating current below that point.
A voltage choke, NOT a current choke placed at a voltage node not at a current node.
That's how I was taught, it's what I see when I look out the window at the GM, but if I'm wrong...
Tom, where are you?
- Come on in and straighten this whole thing out please.
...and the 1/2 wave GM is only 11.2' tall? oops, typo! 
