iow, metric is for wimps.  make mine 50 cal not 12.7mm.  /heh

At 06:23 AM 10/17/2009, Kenneth Wood wrote:
>The USA played golf on the Moon 40 years ago using that old arcane and
>archaic system...Metric system countries that have played golf on the Moon?
>Oh yeah...none
>:)
>
>-----Original Message-----
>From: TechNet [mailto:[log in to unmask]] On Behalf Of Joe Fjelstad
>Sent: Friday, October 16, 2009 4:41 PM
>To: [log in to unmask]
>Subject: Re: [TN] No Soldermask between Fine pitch QFN and QFP
>
>Hello Amol
>
>Since all electronic components are now designed, registered and fabricated
>  using the metric system, would not it be easier to ask for a 0.5mm pitch
>device with lands of 0.25mm by 0.7mm?
>
>This is one of the windmills I continue to joust and I am  constantly
>curious why we in the US continue to be so wedded to such an  arcane and
>archaic
>measurement system as that which we  inherited/adopted from our English
>forefathers.
>
>Consider the following from the web:
>
>The metric system originated in France in the 1790's, a few years after
>Jefferson's proposals. (note: Jefferson proposed to metric English  system
>for
>the US in the 1780 time frame where there were to 10 inches to  the foot,
>10 feet to a decade, 100 feet to a rood, 1000 feet to the furlong  and
>10,000
>feet to the mile) During the mid-nineteenth century, as expanding  trade
>demanded a consistent set of measurements, use of the metric system spread
>through continental Europe. As they imported goods from Europe or exported
>goods  to Europe, Americans became increasingly aware of the metric system.
>In
>1866,  Congress legalized its use in an act reading:
>It shall be lawful throughout the United States of America to employ the
>weights and measures of the metric system; and no contract or dealing, or
>pleading in any court, shall be deemed invalid or liable to objection
>because
>the weights or measures expressed or referred to therein are weights or
>measures of the metric system.
>As a result, the U. S. has been "metric" since 1866, but only in the sense
>that Americans have been free since that time to use the metric system as
>much  as they like. Although there has always been popular resistance to
>changing the  traditional measures, the metric system has actually enjoyed
>strong support from  American business leaders and scientists since the late
>
>nineteenth century. In  1875, the U.S. was one of the original signers of
>the
>Treaty of the Meter."
>and I might add that we continue to move towards complete metrication of
>our  national measurement systems "inch by inch"... ;-)
>Joe
>
>
>In a message dated 10/16/2009 10:55:25 A.M. Pacific Daylight Time,
>[log in to unmask] writes:
>
>I am  looking at a 19.7 mil pitch QFN device with a center pad and
>peripheral pads  at 9.8x27.5 mils, and a 176 pin fine pitch QFP with 11.8x63
>mil
>pads with HASL  finish and without any soldermask in between the peripheral
>pads!...has  anybody seen this type of a board design before? Any stencil
>design  suggestions?
>
>I have a couple of pictures I have requested Steve to post  for me
>regarding the parts ( I am awaiting Steve's  reply)
>
>
>Thanks,
>Amol
>
>
>
>
>
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