Well, I built some antennas. Yagis for 6m, 2m, 70cm and 23cm. It was time consuming but generally successful as all four antennas tested perfectly … until I put them up!
Getting the 6m and 2m antennas along with a refurbished rotator up on the pole on the carport roof was not an easy job but I managed it despite age and creeping arthritis. It was all good until I put the antenna analyser on them. The antennas which tested just fine 3 to 4 metres above the ground were way off at 3 to 4 metres above the metal carport roof. So much so that I’ve had to pull the 6m Yagi down to try re-tuning it. I expected perhaps some minor de-tuning but this was dramatic. An antenna with a 1.1:1 VSWR 4 metres above the ground is 2:1 or worse when up on the pole. It’s disappointing and frustrating.
I even went as far as trying to tune the 6m Yagi while up on the carport roof but that proved just too awkward. I can see this is not going to be a straightforward job.