Chopcat

Helicopters and more

My That's a Whopper

After the first 144mhz UKAC this year I found I was being out gunned with my 7 element LFA and a quick look at the competition shows they are all using higher gain antennas. So I had a chat with Justin of Innov Antennas fame and he has sent me the dimensions for a 14 and 13 element LFA yagi.
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I went for the 13 element (lucky for some) which is 8m long. I have made it in 2 bits using the innovantennas 144mhz choke balun. I have added a new section to the mast that makes it easier to out the beam up a couple of supporting lines to keep it straight. In the driveway is is ok to put up and it will probably be just the wind that might be an issue at MP.

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I have managed to get 1:1.3 VSWR over the SSB band. It wants to be fully resonant at 145 but i can’t seem to change that with different reflectors and directors.

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Tuning consist of standing on a ladder and tapping the LFA elements in and out with a spare bit of aluminium. I expect the VSWR to change when i get it up to its full height but can only do so much without going out with it.

It will be interesting to see how it performs.
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