Thread: Magnetic Loops
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Old October 22nd 15, 03:43 PM posted to rec.radio.amateur.antenna
Brian Howie Brian Howie is offline
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Default Magnetic Loops

On Wed, 21 Oct 2015 05:15:18 -0500, amdx wrote:


30pf per ft is a general number for capacitance of coax, but you know
it varies with type. I have some coax for automobile radio antennas
(AM/FM) that has 8pf per foot.
Mikek



Well its not real coax , but the diameter is about 5ft ( well its
octagonal ) say 15ft circumferance , There's 7 turns in close
proximity to the tube or each other, so the capacitance could be a few
hundred pf . I suppose could try measuring it. Self resonance with
12 turns was about 400KHz

http://www.angelfire.com/mb/amandx/loop.html


so effective minimumum capacitance works out around 100pf

Brian


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