I'm a newbie who is attempting to build a half-wave dipole antenna that will be located in the rudder of a sailplane. 123.3 MHz is the most important frequency to me, although it's reasonable to assume that the antenna should be wide-band enough to work adequately down to 118 MHz and up to 136 MHz. Based on these requirements, and based on a whole lot of internet reading, using some copper tape about 1/2 in wide and 45 inches long (0.47 lambda) is a good starting point for a resonant half-wave dipole antenna centered on 123.3 MHz. I would expect this antenna will be around 73 ohms of inductance (more or less because I expect some coupling to the carbon fiber structure of the aircraft).
So my question is, given that I'm feeding this with around 5 watts of power through 50 ohm RG-400 coax, I'm struggling with how to approach matching the inductance and adding a balun between the coax and the antenna?
It seems like a gamma match might be a good choice, but there are a bewildering number of choices here and it's hard to get a handle on where to even get started with this design. It's probably worth mentioning that the rudder is small, thin, and needs to stay very light weight.