Alessio is correct.. The American ham should have said AWG14 (American Wire
Gauge..since there is also a SWG (standard), a BWG (British), and for all I
know a MWG (Martian Wire Gauge), not to mention all the various gauges for
things like sheet metal (ferrous or not, shotgun shell pellets, shotgun
shells, etc.etc.etc.).
The AWG system has (generally) constant ratios between adjacent gauges. A
difference of 10 gauges is 10 times the area and 20 gauges is 10 times the
diameter. So, a AWG10 wire is about 0.100 inches in diameter, so a AWG20
wire is .0316 (1/10th the area), and a AWG30 is .010 inches. (There's a
fairly loose tolerance on these things, and each mfr has different precise
sizes for a given gauge).
The historical background has to do with how wire is made. You start with a
big bar, and draw it through successively smaller dies, reducing it a bit
each time. The spacing between gauges is about the amount you could shrink
it (with 19th century technology) in one step. So... if you had AWG0 wire,
and you needed AWG10, you'd be running it through a succession of 10 dies.
Modern manufacturing does much more reduction in one step (and can produce
nifty stuff like various clad wires (e.g. Copperweld(tm)) or square or
triangular wire). Of some interest also is that some times, the
specification is for resistance per length, rather than diameter; this takes
into account that the conductivity of the copper being used might change a
bit with composition. So, don't go using copper magnet wire as a feeler
gage.
Some other handy things to remember about wire gauges.. 3 gauges is half the
area, 6 is half the diameter (just like dB!)
To directly answer the original question... AWG 14 is about 0.063 inches in
diameter, or 1.6mm, about 2 sq mm.
AWG 17 is about 1 square mm in cross section
AWG 18 is almost exactly 1mm in diameter
----- Original Message -----
From: "IZ4EFN Alessio" <iz4efn@libero.it>
To: <towertalk@contesting.com>
Sent: Thursday, October 21, 2004 10:17 AM
Subject: [TowerTalk] #14 wire
> Hi guys,
>
> a friend asked me this:
>
> "What should I immagine when an American Ham tells me to use a #14 wire
> for my antenna?"
>
> I believe that the #14 stands for the wire section, but I'm not sure.
>
> Thanks, Alessio IZ4EFN.
> _______________________________________________
>
> 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.
>
> _______________________________________________
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_______________________________________________
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.
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