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From: elec140@canterbury.ac.nz
Newsgroups: sci.electronics
Subject: Re: A conundrum about the AWG (wire gauge) table
Message-ID: <1990Sep13.173238.9156@canterbury.ac.nz>
Date: 13 Sep 90 10:35:41 GMT
References: <2588@ryn.esg.dec.com> <5170089@hplsla.HP.COM>
Organization: University of Canterbury
Lines: 35

In article <5170089@hplsla.HP.COM>, tomb@hplsla.HP.COM (Tom Bruhns) writes:
> jeffw@midas.WR.TEK.COM (Jeff Winslow) writes:
>>In article <5170088@hplsla.HP.COM> tomb@hplsla.HP.COM (Tom Bruhns) writes:
>>>Dunno how it all got started, but you should note that a change of
>>>3 in gauge number corresponds exactly to a 2:1 cross-section change.
>
>>Are you sure about that, Tom? According to the tables I have here, it's
>>about half a percent off.
>
>>I wouldn't even mention it, except that another poster kept coming up
>>with a 1.007 ratio and was wondering why it wasn't exactly 1. I don't know
>>the answer either, but it might have something to do with the fact that
>>1.007 is just about the ratio of the square root of 10 to pi.
>
>>						Jeff Winslow
>>----------

Just to add more fuel to the fire, if you use decibels (defined as 10log(x),
where the log is base 10 and the x is a ratio) then a ratio of 2 is 3.01dB.
Decibels are a common engineering unit (at least in Electrical Engineering), so
perhaps the gauges sizes are based on this.

--
*********************************************************
Chris Kaiser
Postgrad - Elec Eng Dept
Canterbury University
Christchurch, NEW ZEALAND

E.MAIL: c.kaiser@elec.canterbury.ac.nz
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	"When you're fresh out of lawyers
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