Re: HF Ae wire length/diameter ratio & bandwidth
If you are talking about SWR bandwidth and simple HF antennas such as dipoles, the wire gauge doesn't have a dramatic effect.
For example, the 2:1 SWR bandwidth of a 40m dipole goes from 300kHz to 400kHz if you change the wire from #18 gauge to 0.5" diameter. You would need to form several wires into a "cage" to get any major increase.
I'll see if I can find a chart in my various books.
PS: some data in Table 1 here:
http://w4rnl.net46.net/bw.html" Notice also that it takes nearly a 100:1 wire size increase to double the bandwidth of the antenna on any given frequency"
Steve G3TXQ