When I look to my backyard (17m)  could it be a lot worse here in the Netherlands. A half G5RV is no problem. What could I do with the space I have so that the signals on 80m will be stronger (for local operations)? Extending the antenna with loading coils decreases the bandwidth and may introduce problems on the other bands. An other method is lineair loading. That means a zig zag antenne. Mechanical is the length the same as a half size G5RV, but electrically the antenna is 2 x 23m. This size is not based on any theoretical calculations, but just on the length of my garden.
The balun goes via the tuner to the HF-TRX. The results on 80 and 40m are a lot stronger. On 80m the signals are 2-3 S-points stronger. Also on 20m works this antenna very good. The pictures below speak for them self.
the basic, this must grow to an antenna.
is it growing, no its just a lot of wire
Hey friend, would you like me to help? No, I wanna play.
It realy starts looking an antenna
One end of the Cobra
the 1:4 balun