There is another way to do it. After the initial run of 200 feet or so,
you can install a simple in-line booster transformer, which will step the
voltage back up to 12 volts after the slight loss at that point. I don't
recall the price range, but I don't think they cost much.
I don't recall what **exact** name they give it, but it is in fact a
step-up transformer, and is made for the exact circumstance that you
Good Luck !!