OK, having the first turn near the reflector is one technique to get a 50 Ohm match.
?You may try moving it a bit closer to the reflector while watching 2.4 GHz response.?
Next is that boom??? When we put a 50 Ohm trace on a circuit board, the dielectric?
slows down the waves.?? The now travel about 60% the speed of free space.
When that boom touches the helix, or to a smaller amount, simply gets near it,
you get a similar effect.??? Now the Turns/Diameter ratio of the helix is altered.A few pieces of styrofoam supporting the helix might help.
So you might try moving that first turn in an out a bit.? And you often see quite a??
change when you snip a few millimeters on the end.?? But I just don't see a lot of
hours in it's engineering, if you know what I mean.? .Good luck with your project. Kent
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On Wednesday, November 4, 2020, 12:03:20 PM CST, aleatorii.yg@... <aleatorii.yg@...> wrote:
Thanks for the reply, attached are some photos. Note this was sold in the UK as a 13cm antenna (I think by Sandpiper, but I may be wrong), many years ago.
I've never actually built a helix design myself, so am not that clued up on any theory of them.
