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Inductance calculations

Started by Peter Percival August 20, 2019
Somewhere there must be a formula for the inductance of a hand-wound coil.

Air core, one layer of wire (of given swg) close-wound, diameter of 
former (cardboard, probably inside of toilet paper roll), length of 
coil,... (what else?), therefore inductance equals ...
On Tue, 20 Aug 2019 15:07:07 +0100, Peter Percival
<peterxpercival@hotmail.com> wrote:

>Somewhere there must be a formula for the inductance of a hand-wound coil. > >Air core, one layer of wire (of given swg) close-wound, diameter of >former (cardboard, probably inside of toilet paper roll), length of >coil,... (what else?), therefore inductance equals ...
of course there are. Your google is broken? BTW single layer solenoid-wound coils usually hit the calculate values spot-on, it doesn't start to get hairy until you add layers. There's a formula that takes into consideration the diameter/length ratio too, but for simple single layer coils try the "Amateur Radio Handbook."
On 8/20/2019 9:07 AM, Peter Percival wrote:
> Somewhere there must be a formula for the inductance of a hand-wound coil. > > Air core, one layer of wire (of given swg) close-wound, diameter of > former (cardboard, probably inside of toilet paper roll), length of > coil,... (what else?), therefore inductance equals ...
Yep a dozen. I have spreadsheeet labeled the Nagaoka Formula that is supposed to be very accurate. You can search for it, But I think these use his formula,
> http://www.mogami.com/e/cad/coil-01.html
If you want a deep understanding, with Nagaoka.
> http://mathscinotes.com/wp-content/uploads/2014/04/lundin_Proc_IEEE_1985.pdf
Otherwise, dig into these. Or just the first one.
> http://crystalradio.net/professorcoyle/professorcoylecyl.shtml
> http://electronbunker.ca/eb/InductanceCalc.html
> https://www.translatorscafe.com/unit-converter/ja/calculator/coil-inductance/?D=2&Du=cm&l=1&lu=cm&N=10
use the second on this page.
> http://www.circuits.dk/calculator_single_layer_aircore.htm
> http://www.66pacific.com/calculators/coil-inductance-calculator.aspx
> https://coil32.net/online-calculators/one-layer-coil-calculator.html
> https://hamwaves.com/inductance/en/index.html#input
> https://www.qsl.net/in3otd/indcalc.html
> https://knowpapa.com/inductance/
That's enough so you will never know who is correct :-) I ecpect The ones I have used is Professor Coyle, and I had a downloaded version, so haven't tried the online version and electronbunker. Mikek
amdx wrote:
> On 8/20/2019 9:07 AM, Peter Percival wrote: >> Somewhere there must be a formula for the inductance of a hand-wound >> coil. >> >> Air core, one layer of wire (of given swg) close-wound, diameter of >> former (cardboard, probably inside of toilet paper roll), length of >> coil,... (what else?), therefore inductance equals ... > > &nbsp;Yep a dozen. > &nbsp;I have spreadsheeet labeled the Nagaoka Formula that is supposed to be > very accurate. You can search for it, But I think these use his formula, > >> http://www.mogami.com/e/cad/coil-01.html > > > If you want a deep understanding, with Nagaoka. >> http://mathscinotes.com/wp-content/uploads/2014/04/lundin_Proc_IEEE_1985.pdf >> > > Otherwise, dig into these. Or just the first one. > >> http://crystalradio.net/professorcoyle/professorcoylecyl.shtml > >> http://electronbunker.ca/eb/InductanceCalc.html > > >> https://www.translatorscafe.com/unit-converter/ja/calculator/coil-inductance/?D=2&Du=cm&l=1&lu=cm&N=10 >> > > use the second on this page. > >> http://www.circuits.dk/calculator_single_layer_aircore.htm > >> http://www.66pacific.com/calculators/coil-inductance-calculator.aspx > >> https://coil32.net/online-calculators/one-layer-coil-calculator.html > >> https://hamwaves.com/inductance/en/index.html#input > >> https://www.qsl.net/in3otd/indcalc.html > >> https://knowpapa.com/inductance/ > > &nbsp;That's enough so you will never know who is correct :-) > I ecpect > > The ones I have used is Professor Coyle, and I had a downloaded version, > so haven't tried the online version and electronbunker. > > &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Mikek >
Ooh, there's lots! Thank you.
On 8/20/2019 9:07 AM, Peter Percival wrote:
> Somewhere there must be a formula for the inductance of a hand-wound coil. > > Air core, one layer of wire (of given swg) close-wound, diameter of > former (cardboard, probably inside of toilet paper roll), length of > coil,... (what else?), therefore inductance equals ...
If your getting into crystal radio, You might find this interesting,
> http://theradioboard.com/rb/viewforum.php?f=2
and this overwhelming,
> http://makearadio.com/crystal/index.php
Mikek
A first approach :
&micro;0*N^^2*S/L.
Parasistic elements are uncomputable.


Peter Percival a &eacute;crit le 20/08/2019 &agrave; 16:07&nbsp;:
> Somewhere there must be a formula for the inductance of a hand-wound > coil. > > Air core, one layer of wire (of given swg) close-wound, diameter of > former (cardboard, probably inside of toilet paper roll), length of > coil,... (what else?), therefore inductance equals ...