[Lowfer] I need the formula to calculate needed turns on a coil

[Paul Daulton]

Thanks for the reminder, Warren. Also wire size is not a factor just 
dia, # of turns, and length, so any wire size could be used for the 
trial? No need to cut up the 14 awg. 

I have an antique ARRL lightning calculator, a circular slide rule for 
calculating inductance and resonance that is helpful, but it doesnt go 
large enough for what we are working with. Arrl sells a newer version 
which is a horizontal sliderule calculator for about $12. I dont know 
the capacity of this version. 

Andy If you make a trial winding with smaller wire try paralleling the 
wire with a piece of string to space the wire out to give the # of 
turns per inch that 14awg does. 

Paul

Quoting Warren Ziegler <wd2xgj at gmail.com>:
> Paul, Andy,
>
> >  You can
> > wind 10 turns and check that then wind whatever mulitple of 10 turns to
> > get the 2500 uh you want. 
>
>     Remembering of course that inductance goes up with the square of
> the turns count so 20 turns will have 4x the inductance of 10 turns. 
>
> -- 73 Warren K2ORS
>                 WD2XGJ
>                 WD2XSH/23
>                 WE2XEB/2
>                 WE2XGR/1
>
> On Fri, Nov 20, 2009 at 11:38 AM, Paul Daulton <k5wms at centurytel.net> wrote:
> > Andy , Ralph W5JGV has provided us with a nomograph to calculate big
> > coils . see
> > http://w5jgv.com/downloads/indchart.gif  you might want to print this
> > and have it laminated
> > at a copy shop. you might want to back up one level and see
> > http://w5jgv.com/downloads
> > and check out all the neat stuff there. 
> >
> > There are several programs like vertload on the internet but the
> > nomograph is the easiest to use. 
> >
> >  Best I remember you have one of the AADE inductance meters. You can
> > wind 10 turns and check that then wind whatever mulitple of 10 turns to
> > get the 2500 uh you want. 
> >
> > Keep us posted on your progress. 
> >
> > Paul k5wms
> >
> > Quoting Andy - KU4XR <ku4xr at yahoo.com>:
> >> Hi all:
> >>
> >> I hope soon to rewind my LOWfer antenna coil with the #14 soild,
> >> in place of the #28 I'm using now. DC Resistance will be lower,
> >> which in itself will be another improvement in the overall setup. 
> >> I'll be using a white paint bucket this time, and probably a
> >> white, thin walled PVC for the vari-coil, 4" diameter. 
> >> To this point, I have been concentrating on antenna, but now I
> >> need to begin educating myself on optimum coils, and winding. 
> >> I admit right up front that my experience in this area is just
> >> starting. 
> >> I do not want to cut the #14 wire " too short " , so I need to
> >> know how to calculate the number of turns needed for a particular
> >> Inductance. I also don't want to cut it way too long, as this will
> >> be waste.  And, for my education, if the inductace needed for #28
> >> wire is 2.36 mH at resonance, will it be the same for #14 wire ??
> >> That will help me to know this too. 
> >> Any help you gentlemen will offer will be most appreciated. 
> >>
> >> Thank you and 73 to all :::
> >>
> >>
> >> Andy - KU4XR - EM75xr - Friendsville, TN. 
> >> LOWfer Beacon " XR " @ 185.29866 KHz ( QRSS-60 )
> >> Coordinates:  N:  35* 43' 54" - W:  84* 3' 16"
> >> http://www.myspace.com/beaconxr
> >>
> >>
> >>
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> >>
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> >>
> >
> > Paul Daulton K5WMS
> > beacon WMS 187.492 khz qrss30/slow 24/7
> > Jacksonville,Ar 72076
> > em34wu
> >
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> >
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> >
>
>
>
> -- 73 Warren K2ORS
>                 WD2XGJ
>                 WD2XSH/23
>                 WE2XEB/2
>                 WE2XGR/1
>

Paul Daulton K5WMS
beacon WMS 187.492 khz qrss30/slow 24/7
Jacksonville,Ar 72076
em34wu