Tag Archives: 6m

6m Loop Fed Yagi Project

A few years ago, I bought a 6m yagi from Moonraker and James and I used it on one of our private field days. We found it difficult to get a great match but I thought I’d resurrect the project earlier this year to enter some random Saturday contest that was taking place on 6m.

Unfortunately, for love nor money, although I managed to assemble most of the bits, I couldn’t find the gamma match arrangement in all my Tesco boxes. I needed this because unfortunately the impedance of a three element yagi is well under 50 ohms so unless I went for just a two element beam, I would have to re-engineer things. I recall that a loop had a higher impedance, about 100 ohms. Using a closed loop system with a reflector and a director would bring the loop impedance down, probably by about half (according to the modelling) to achieve 50 ohms. I modelled it and things looked very promising. Wide bandwidth and pretty good gain.

Continue reading