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<TITLE>RE: [sdiy] Pressing buttons</TITLE>
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<P><FONT SIZE=2>> If you use a 4-16 line decoder... hook up the switches to</FONT>
<BR><FONT SIZE=2>> data inputs Q1-Q4. Then run a high value feedback resistor</FONT>
<BR><FONT SIZE=2>> from output 1 to Q0, output 2 to Q1, output 4 to Q2, and output</FONT>
<BR><FONT SIZE=2>> 8 to Q3. Then push a button... the corresponding output goes</FONT>
<BR><FONT SIZE=2>> high and latches the input because of the feedback....</FONT>
<BR><FONT SIZE=2>> </FONT>
<BR><FONT SIZE=2>> not my idea, saw it years ago using a 3-8 line decoder in ideas for</FONT>
<BR><FONT SIZE=2>> design</FONT>
<BR><FONT SIZE=2>> or some such...</FONT>
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<P><FONT SIZE=2>Harry is right. It was an "Ideas for Design" topic from EDN from the early 80s. I've used the circuit and it works very well. This is exactly what you want.</FONT></P>
<P><FONT SIZE=2>John Speth</FONT>
<BR><FONT SIZE=2>Molectron Detector, Inc.</FONT>
<BR><FONT SIZE=2><A HREF="http://www.molectron.com" TARGET="_blank">http://www.molectron.com</A></FONT>
<BR><FONT SIZE=2><A HREF="mailto:johns@molectron.com">mailto:johns@molectron.com</A> </FONT>
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