https://en.wikipedia.org/wiki/Setun
Instead of the first bit being 1 or 0, the second being 2 or 0, etc you have different scheme where the first bit is 1, 0, or -1 the second is 3, 0, or -3, etc. So 2 would be 3 + (-1).
In practice, it didn't work out for ternary, either; Setun would use pairs of cores to represent trits.
One of the benefits of being balanced is that it's self-rounding: Just turn any amount of final digits into 0s and you're done. What if you want to express the exact half, decimal 0.5? Well you'll end up with either 1.TTTTT... or 0.11111... so it could round either way. If we were to use this system, shops could no longer manipulate us with prices ending in .99.
Give it a minute to fully grasp the concept and you'll see how intuitive it is.