Length Measured Element in mm Spacing Reflector 350 Folded Dipole Not done Director 1 330 Not done Director 2 315 Not done Director 3 305 Not done Director 4 300 Not done Director 5 297 Not done Director 6 295 Not done Director 7 295 Not done Director 8 290 Not done Director 9 285 Not done Centre of boom Director 10 285 171 Director 11 280 172 Director 12 280 173 Director 13 275 172 Director 14 275 172 Director 15 270 172 Director 16 270 172 Director 17 265 173 Quoted figures Gain 17dBi Aperture -3dB H 2x14ø " V 2x16ø Front-back 23dB Side Lobes > 38dB VSWR ò 1.2 Weight 1.1Kg Length 3.2M Wind load @ 25m/S 5.4Kg 73 de Andy @ GB7SXE.#38.GBR.EU I have found problems the only problem with Tonners of this construction is the ally-ally connections inside the molded connection block. These corrode & you end up with no aerial. Repairs can be done by sawing away at the block until the connection rivet is located. Drill this out & drill & tap in a suitable brass screw after first painting it with silver conductive paint on the screw & tapped hole. Make a paper/tape mold around block & fill in the hole you made with a car repair resin. 73 De John, G8MNY @ GB7CIP