I wanted a simple "get me started" antenna for VHF. I thought I'd had a bright idea in using copper plumbing pipe but it quickly proved to be a very well known method. But in looking for a suitable antenna I came across the J-pole.
I took the basic design from Dale Kubichek, N6JSK web page. I reproduced the metalwork exactly as described. To mount the SO239 connector I used a "jubilee" clip with the end folded out; I used another to clamp the other end of the feed wire.
When rested with an MFJ antenna analyser, the match on 2 metres wasn't great. No problem; the great thing about the analyser is you can find out where the resonances are. Mine were at about 151MHz so I was able to calculate the "extra" length required and join a little more pipe to the antenna. I also optimised the feed positions to get about 1.1:1 VSWR.
Unfortunately, these changes meant the antenna would not work at all on 70cm. My analyser doesn't go that far, so I've no idea what changes are needed. I decided to call it a day and have a working VHF antenna, rather than a non working dual band one.Â