Thinking about my low band Ae's and bandwidth, I'm convinced that in the past I have seen a chart/diagram/nomogram of wire length to diameter ratio against bandwidth. Checked my books and internet but its hiding on me, or was my memory wrong ? Help appreciated. Cliff.

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

Hello Steve, well done. Yes a cage was on my mind, I've heard of 8 inch spreaders to jump the thickness up. That table is a good reference. Yet a chart even better. Thank you. Cliff.

Cliff,

I don't know what application you have in mind, but there are other ways of extending the SWR bandwidth that are mechanically easier to build than a full cage dipole; for example two legs either side of the feedpoint with "staggered" tuning.

73,
Steve G3TXQ

Hello Steve, Hum! story too long for here, back to fan dipole again. Ae system here already has three pairs of elements for four bands, so might have to go for even more wire. Trying my best to not need a tuner for 40m to 160m. Thanks, Cliff.