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<DIV><FONT face=Arial size=2>Hello, </FONT></DIV>
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<DIV><FONT face=Arial size=2>Im trying to fix an edp wasp.</FONT></DIV>
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<DIV><FONT face=Arial size=2>The lowest c is fine, then c#, d, d#, and e
are dead. All other keys are fine.</FONT></DIV>
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<DIV><FONT face=Arial size=2>This specific of 4 dead keys is fed into one half
of a 4052 multiplexer, then to a 4016 switch, and then to a 4028 and
onwards. The other group of 4 keys also utilising the other halves of the
same ics are working fine.</FONT></DIV>
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<DIV><FONT face=Arial size=2>My problem is determining, with my multimeter,
which ic to replace. </FONT></DIV>
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<DIV><FONT face=Arial size=2>Can anyone give me some pointers as to how to
diagnose this.</FONT></DIV>
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<DIV><FONT face=Arial size=2>Laurie's redrawn schematics are
usefull:</FONT></DIV>
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<DIV><FONT face=Arial size=2><A
href="http://www.elby-designs.com/wasp/keyboard.pdf">http://www.elby-designs.com/wasp/keyboard.pdf</A></FONT></DIV>
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<DIV><FONT face=Arial size=2>Cheers, Julian</FONT></DIV>
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