An earlier discussion brought to mind the question of the 3/2 wl
antennas such as using a 40 meter dipole to operate on 15 meters. I
just modeled one using the following stats:

1 wire, 66 feet high, 68.8286 feet long. I then pulled an SWR reading
from it from 3.5 to 30 MHz using .1 increments. The result was, of
course, two dips, one at 7.0 MHz and one at 21.1. By playing with the
alternative impedance, I found that 94 ohms matched both frequencies
at about 1.15:1.

Here are some observations about it.

at 7.0 MHz, the shows:

50 ohms -- 1.65:1
72 ohms -- 1.14:1
75 ohms -- 1.09:1
94 ohms -- 1.14:1

at 21.1 MHz, I get the following:
50 ohms -- 2.16:1
72 ohms -- 1.5:1
75 ohms -- 1.44:1
94 ohms -- 1.15:1


The above are the lowest SWR readings (which is why 21.1 instead of 21
MHz)

so, how does one make a 94 ohm match?


--
73 for now
Buck
N4PGW