What about a tape measure and a pencil? Oh if you want to use paper
instead of something else you may need paper too.
73
Jim W7RY
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Matt Patterson
Sent: Thursday, October 06, 2005 12:05 PM
To: Pat Barthelow; dolanmorrison@tiscali.co.uk; towertalk@contesting.com
Subject: Re: [TowerTalk] Cable on a reel using a formula?
Isn't the formula pi * radius(squared) * the number of turns what you
need?
Been a long time since I did any geometry...
Matt
----- Original Message -----
From: "Pat Barthelow" <aa6eg@hotmail.com>
To: <dolanmorrison@tiscali.co.uk>; <towertalk@contesting.com>
Sent: Thursday, October 06, 2005 12:22 PM
Subject: Re: [TowerTalk] Cable on a reel using a formula?
>
>>How
>>to calculate the amount of cable on a reel using a formula?
>>Anybody know this formula.
>>GM0LZE
>
> I used to have an Allied Electronics reference guide from the 60s
> That had a formula for big audio inductors where the bobbin
> dimensions(diameter and spool length)
> the wire diameter were entered and it could calculate inductance,
> resistance....
>
> Hmmm...mebbe a better way...er two better ways...if the cable is newly
> manufactured, it often
> has foot or metre markers with numbers marked on the jacket every
> foot..look at both ends and subtract...but that would be too easy..
so
> probably not an option in your case...
> If Coax, and very long, take a good hi res ohmmeter, short one end,
and
> measure the
> loop resistance and look up the factory loop resistance figures for
that
> kind of cable..so
>
> Maybe some old solenoid design engineering formulas can be had to do
the
> trick....
>
> Or, Get an MFJ 259B, and connectorize the free spool end, and use the
> legth
> function of the 259B to calculate the length to the end...
>
> 73, DX Pat AA6EG aa6eg@hotmail.com
>
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers",
"Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041
with
> any questions and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
any questions and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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