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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>The Kraft KPS-9 servo that Kraft sold with the Gold Medal
radios had the variable cap. Not sure about what may have come before it. This
was the same servo mechanics that Heathkit sold with the GD-17 and GD-19 (eventually
replaced by the KPS-11 and KPS-12 servo mechanics on the GD-19). Still have a
box full of KPS-9’s from the Heathkits and they mostly work. All the later
Kraft servos used a carbon element pot.<o:p></o:p></span></p>
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color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Ed<o:p></o:p></span></p>
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<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
nsrca-discussion-bounces@lists.nsrca.org
[mailto:nsrca-discussion-bounces@lists.nsrca.org] <b>On Behalf Of </b>Bob
Richards<br>
<b>Sent:</b> Monday, June 22, 2009 1:06 PM<br>
<b>To:</b> General pattern discussion<br>
<b>Subject:</b> Re: [NSRCA-discussion] Servo Signals<o:p></o:p></span></p>
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<p class=MsoNormal>Yes, as long as they are clean. That is the problem, it
depends on contact between two components and the friction wears them out.<o:p></o:p></p>
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<p class=MsoNormal> <o:p></o:p></p>
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<p class=MsoNormal>I remember years ago that the large heathkit (and possibly
some Kraft) servos used variable capacitors for feedback. not much to wear.<o:p></o:p></p>
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<p class=MsoNormal> <o:p></o:p></p>
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<p class=MsoNormal>Ok, Jay, how long ago were the "days" you were
talking about? :-) <o:p></o:p></p>
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<p class=MsoNormal> <o:p></o:p></p>
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<p class=MsoNormal>Bob R.<o:p></o:p></p>
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<p class=MsoNormal><br>
<br>
--- On <b>Sun, 6/21/09, Jay Marshall <i><lightfoot@sc.rr.com></i></b>
wrote:<o:p></o:p></p>
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<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'>I
remember from my days in control systems theory that the analog computers
were faster and more accurate than the IBM big iron computers. Analog pots
are still cheaper, lighter, and higher resolution than digital encoders – as
long as they are clean…</span><o:p></o:p></p>
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<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'><o:p> </o:p></span></p>
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