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<DIV><FONT face="MS Sans Serif" size=2>My radio shack soundmeter was off by
almost 3 dB when it was calibrated. </FONT></DIV>
<DIV><FONT face="MS Sans Serif" size=2> </FONT></DIV>
<DIV><FONT face="MS Sans Serif" size=2><STRONG>
</STRONG>Del</FONT></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=ehaury@houston.rr.com href="mailto:ehaury@houston.rr.com">Earl
Haury</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=discussion@nsrca.org
href="mailto:discussion@nsrca.org">discussion@nsrca.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Saturday, April 24, 2004 9:05
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: sound meter</DIV>
<DIV><BR></DIV>
<DIV><FONT face=Arial size=2>Steve</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>It matters a lot. The rules specify dB-A, so use
the A scale. Without a calibrator most sound meters, even the expensive
variety, are really only good for comparative measurements. So - use it to
find what makes the airplane quieter but don't get fixated on the absolute
number without a calibrated reference.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Earl</FONT></DIV></BLOCKQUOTE></BODY></HTML>