Once I get my licence, I would like to get a doublet antenna up to
work as many HF bands as possible. The problem is that down one side
of my garden there are power lines and at the bottom of the other side
of the garden is a two story flat/apartment. If I have the dipole
running down the power line side of the garden it will have to slope
from about 40feet to about 20 feet. Will this be a problem with
regards to the balance of the antenna and cause any problems such as
RF in the shack etc?

The alternative is to get some kind of thin pole and have one end of
the antenna right outside one of the flats kitchen window which I'm
not to keen on.

Any advice appreciated

Peter