Indoor Antenna for 40 Meters

I'm going to try and set up an antenna for 40 meters in my attic as a small experiment. It was originally produced by F6CYV and I came across it on the web the other day whilst browsing. He reckons it pretty good having worked over 150 separate countries around Europe.

The actual antenna is made up of 2mm wire, the 2 coils are made up of 18 turns of 2mm wire and the distance of turns is also 2mm.
The diameter of the coils is 7/8 cm and the coax feed is comprised of 75 ohms, an old TV cable should do. But for a good feed from coax to the dipole a 1:1 Balun would help.

I'll let you know how it goes!