Radio’s

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Ken Raven
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Radio’s

Post by Ken Raven » Wed Dec 30, 2020 5:10 pm

What would be a good size for an aerial ground plan in a plastic plane ?
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tnowak
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Re: Radio’s

Post by tnowak » Thu Dec 31, 2020 6:24 am

As large as you can fit.
But I would suggest a minimum of 6 x 6".

Is this to fit an antenna to an already constructed aircraft?

Tony
Tony Nowak
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Ken Raven
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Re: Radio’s

Post by Ken Raven » Thu Dec 31, 2020 6:39 am

Yes, But good a access to rear fuselage.
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Ian Melville
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Re: Radio’s

Post by Ian Melville » Thu Dec 31, 2020 4:43 pm

Radius of the ground plane should be at least 1/4 wave length, and flat. So if it is in the curved inner skin of the turtle deck, you will need to widen it, about 0.6M radius or as large as practical.
Simply put the radius of the ground-plane must be greater than the height of the antenna. The ground plane should be horizontal in flight and the antenna perpendicular to it.

Raked antennas may look cool, but they degrade radio performance. However a small amount of rake forward if top mounted or back on the underside would be acceptable.
Ian Melville
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Ian Melville
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Re: Radio’s

Post by Ian Melville » Thu Dec 31, 2020 4:51 pm

Oh, and get the VSWR checked. I have seen off the shelf antennas fitted with no tuning. They were supplied for the Nav band which is lower in frequency and needed to be trimmed.
Ian Melville
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Sean McDonald
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Re: Radio’s

Post by Sean McDonald » Thu Dec 31, 2020 5:16 pm

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Last edited by Sean McDonald on Fri Jan 01, 2021 6:36 pm, edited 1 time in total.

Ian Melville
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Re: Radio’s

Post by Ian Melville » Thu Dec 31, 2020 7:58 pm

I was going to make the same suggestion, but wanted to keep my post to what was asked by the OP and not confuse things. You do have to be mindful of control runs.
Ian Melville
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