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<title>The Class-A Amplifier Site</title>
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<p align=right style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:1.0cm;margin-bottom:.0001pt;text-align:right'><b>The Class-A
Amplifier Site</b></p>
<p align=right style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:1.0cm;margin-bottom:.0001pt;text-align:right'><span
style='font-size:10.0pt'>This page was last updated on 17August 2003</span></p>
<p style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;margin-left:1.0cm;
margin-bottom:.0001pt'><b><a href="index.htm" title=index.htm>[ Back to Main
Index ]</a></b></p>
<p style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;margin-left:1.0cm;
margin-bottom:.0001pt'>&nbsp;</p>
<p style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;margin-left:1.0cm;
margin-bottom:.0001pt'>&nbsp;</p>
<p align=center style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:1.0cm;margin-bottom:.0001pt;text-align:center'><b><span
style='font-size:20.0pt'>Classic Class-B Schematics</span></b></p>
<p align=center style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:1.0cm;margin-bottom:.0001pt;text-align:center'><b>&nbsp;</b></p>
<p style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;margin-left:1.0cm;
margin-bottom:.0001pt'>Though these schematics are not for Class-A amplifiers, I
thought they might be useful for anyone intending to modify or repair these
classic commercial designs.</p>
<p style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;margin-left:1.0cm;
margin-bottom:.0001pt'>&nbsp;</p>
<p style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;margin-left:1.0cm;
margin-bottom:.0001pt'><a name=index></a><b><span style='font-size:16.0pt'>Index</span></b></p>
<p style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;margin-left:1.0cm;
margin-bottom:.0001pt'>&nbsp;</p>
<table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 width="100%"
style='width:100.0%;border-collapse:collapse'>
<tr>
<td width="77%" valign=top style='width:77.76%;padding:0cm 0cm 0cm 0cm'>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:1.0cm;margin-bottom:.0001pt;text-align:left'><b>NAD 3020</b></p>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:1.0cm;margin-bottom:.0001pt;text-align:left'>&nbsp;</p>
</td>
<td width="22%" valign=top style='width:22.24%;padding:0cm 1.0cm 0cm 0cm'>
<p align=right style='margin-top:0cm;margin-right:5.65pt;margin-bottom:0cm;
margin-left:5.65pt;margin-bottom:.0001pt;text-align:right'><span
style='font-size:10.0pt'>&nbsp;</span></p>
</td>
</tr>
<tr>
<td width="77%" valign=top style='width:77.76%;padding:0cm 0cm 0cm 0cm'>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'><b><a
href="nad3020pre.gif" title=nad3020pre.gif>Pre-amp</a></b></p>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'>&nbsp;</p>
</td>
<td width="22%" valign=top style='width:22.24%;padding:0cm 1.0cm 0cm 0cm'>
<p align=right style='margin-top:0cm;margin-right:5.65pt;margin-bottom:0cm;
margin-left:5.65pt;margin-bottom:.0001pt;text-align:right'><span
style='font-size:10.0pt'><a href="nad3020pre.gif" title=nad3020pre.gif><span
style='color:windowtext;text-decoration:none'><img border=0 width=28
height=31 src="gif.gif"></span></a></span></p>
</td>
</tr>
<tr>
<td width="77%" valign=top style='width:77.76%;padding:0cm 0cm 0cm 0cm'>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'><b><a
href="nad3020pwr.gif" title=nad3020pwr.gif>Power Amplifier</a></b></p>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'>&nbsp;</p>
</td>
<td width="22%" valign=top style='width:22.24%;padding:0cm 1.0cm 0cm 0cm'>
<p align=right style='margin-top:0cm;margin-right:5.65pt;margin-bottom:0cm;
margin-left:5.65pt;margin-bottom:.0001pt;text-align:right'><span
style='font-size:10.0pt'><a href="nad3020pwr.gif" title=nad3020pwr.gif><span
style='color:windowtext;text-decoration:none'><img border=0 width=28
height=31 src="gif.gif"></span></a></span></p>
</td>
</tr>
<tr>
<td width="77%" valign=top style='width:77.76%;padding:0cm 0cm 0cm 0cm'>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'><b><a
href="nad3020pwrhr.gif" title=nad3020pwrhr.gif>Power Amplifier</a>&nbsp; </b>(Single
channel at a higher resolution)</p>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'>&nbsp;</p>
</td>
<td width="22%" valign=top style='width:22.24%;padding:0cm 1.0cm 0cm 0cm'>
<p align=right style='margin-top:0cm;margin-right:5.65pt;margin-bottom:0cm;
margin-left:5.65pt;margin-bottom:.0001pt;text-align:right'><span
style='font-size:10.0pt'><a href="nad3020pwrhr.gif" title=nad3020pwrhr.gif><span
style='color:windowtext;text-decoration:none'><img border=0 width=28
height=31 src="gif.gif"></span></a></span></p>
</td>
</tr>
<tr>
<td width="77%" valign=top style='width:77.76%;padding:0cm 0cm 0cm 0cm'>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'><b><a
href="nad3020ps.gif" title=nad3020ps.gif>Power Supply</a></b></p>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'>&nbsp;</p>
</td>
<td width="22%" valign=top style='width:22.24%;padding:0cm 1.0cm 0cm 0cm'>
<p align=right style='margin-top:0cm;margin-right:5.65pt;margin-bottom:0cm;
margin-left:5.65pt;margin-bottom:.0001pt;text-align:right'><span
style='font-size:10.0pt'><a href="nad3020ps.gif" title=nad3020ps.gif><span
style='color:windowtext;text-decoration:none'><img border=0 width=28
height=31 src="gif.gif"></span></a></span></p>
</td>
</tr>
<tr>
<td width="77%" valign=top style='width:77.76%;padding:0cm 0cm 0cm 0cm'>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:1.0cm;margin-bottom:.0001pt;text-align:left'><b>Cyrus 1</b></p>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:1.0cm;margin-bottom:.0001pt;text-align:left'>&nbsp;</p>
</td>
<td width="22%" valign=top style='width:22.24%;padding:0cm 1.0cm 0cm 0cm'>
<p align=right style='margin-top:0cm;margin-right:5.65pt;margin-bottom:0cm;
margin-left:5.65pt;margin-bottom:.0001pt;text-align:right'><span
style='font-size:10.0pt'>&nbsp;</span></p>
</td>
</tr>
<tr>
<td width="77%" valign=top style='width:77.76%;padding:0cm 0cm 0cm 0cm'>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'><b><a
href="cyrus1inp.gif" title=cyrus1inp.gif>Input Switching &amp; Volume Control</a></b></p>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'>&nbsp;</p>
</td>
<td width="22%" valign=top style='width:22.24%;padding:0cm 1.0cm 0cm 0cm'>
<p align=right style='margin-top:0cm;margin-right:5.65pt;margin-bottom:0cm;
margin-left:5.65pt;margin-bottom:.0001pt;text-align:right'><span
style='font-size:10.0pt'><a href="cyrus1inp.gif" title=cyrus1inp.gif><span
style='color:windowtext;text-decoration:none'><img border=0 width=28
height=31 src="gif.gif"></span></a></span></p>
</td>
</tr>
<tr>
<td width="77%" valign=top style='width:77.76%;padding:0cm 0cm 0cm 0cm'>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'><b><a
href="cyrus1phono.gif" title=cyrus1phono.gif>Phono Stage</a></b></p>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'>&nbsp;</p>
</td>
<td width="22%" valign=top style='width:22.24%;padding:0cm 1.0cm 0cm 0cm'>
<p align=right style='margin-top:0cm;margin-right:5.65pt;margin-bottom:0cm;
margin-left:5.65pt;margin-bottom:.0001pt;text-align:right'><span
style='font-size:10.0pt'><a href="cyrus1phono.gif" title=cyrus1phono.gif><span
style='color:windowtext;text-decoration:none'><img border=0 width=28
height=31 src="gif.gif"></span></a></span></p>
</td>
</tr>
<tr>
<td width="77%" valign=top style='width:77.76%;padding:0cm 0cm 0cm 0cm'>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'><b><a
href="cyrus1pwr.gif" title=cyrus1pwr.gif>Power Amplifier</a></b></p>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'>&nbsp;</p>
</td>
<td width="22%" valign=top style='width:22.24%;padding:0cm 1.0cm 0cm 0cm'>
<p align=right style='margin-top:0cm;margin-right:5.65pt;margin-bottom:0cm;
margin-left:5.65pt;margin-bottom:.0001pt;text-align:right'><span
style='font-size:10.0pt'><a href="cyrus1pwr.gif" title=cyrus1pwr.gif><span
style='color:windowtext;text-decoration:none'><img border=0 width=28
height=31 src="gif.gif"></span></a></span></p>
</td>
</tr>
<tr>
<td width="77%" valign=top style='width:77.76%;padding:0cm 0cm 0cm 0cm'>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'><b><a
href="cyrus1ps.gif" title=cyrus1ps.gif>Power Supply</a></b></p>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'><span
style='font-size:11.0pt'>&nbsp;</span></p>
</td>
<td width="22%" valign=top style='width:22.24%;padding:0cm 1.0cm 0cm 0cm'>
<p align=right style='margin-top:0cm;margin-right:5.65pt;margin-bottom:0cm;
margin-left:5.65pt;margin-bottom:.0001pt;text-align:right'><span
style='font-size:10.0pt'><a href="cyrus1ps.gif" title=cyrus1ps.gif><span
style='color:windowtext;text-decoration:none'><img border=0 width=28
height=31 src="gif.gif"></span></a></span></p>
</td>
</tr>
<tr>
<td width="77%" valign=top style='width:77.76%;padding:0cm 0cm 0cm 0cm'>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:1.0cm;margin-bottom:.0001pt;text-align:left'><b>Sugden A48-II</b></p>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:1.0cm;margin-bottom:.0001pt;text-align:left'><span
style='font-size:11.0pt'>&nbsp;</span></p>
</td>
<td width="22%" valign=top style='width:22.24%;padding:0cm 1.0cm 0cm 0cm'>
<p align=right style='margin-top:0cm;margin-right:5.65pt;margin-bottom:0cm;
margin-left:5.65pt;margin-bottom:.0001pt;text-align:right'><span
style='font-size:10.0pt'>&nbsp;</span></p>
</td>
</tr>
<tr>
<td width="77%" valign=top style='width:77.76%;padding:0cm 0cm 0cm 0cm'>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'><b><a
href="sugdena48.gif" title=sugdena48.gif>Schematic</a></b></p>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'><b>&nbsp;</b></p>
</td>
<td width="22%" valign=top style='width:22.24%;padding:0cm 1.0cm 0cm 0cm'>
<p align=right style='margin-top:0cm;margin-right:5.65pt;margin-bottom:0cm;
margin-left:5.65pt;margin-bottom:.0001pt;text-align:right'><span
style='font-size:10.0pt;color:black'><a href="sugdena48.gif"
title=sugdena48.gif><span style='color:black;text-decoration:none'><img
border=0 width=28 height=31 src="gif.gif"></span></a></span></p>
</td>
</tr>
<tr>
<td width="77%" valign=top style='width:77.76%;padding:0cm 0cm 0cm 0cm'>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'><b><a
href="sugden-a48.png" title=sugdena48.png>Parts List</a></b></p>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:42.55pt;margin-bottom:.0001pt;text-align:left'><b>&nbsp;</b></p>
</td>
<td width="22%" valign=top style='width:22.24%;padding:0cm 1.0cm 0cm 0cm'>
<p align=right style='margin-top:0cm;margin-right:5.65pt;margin-bottom:0cm;
margin-left:5.65pt;margin-bottom:.0001pt;text-align:right'><b><span
style='font-size:10.0pt;color:red'><a href="sugden-a48.png"><img border=0 width=28 height=31
src="gif.gif"></a></span></b></p>
</td>
</tr>
</table>
<p style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;margin-left:1.0cm;
margin-bottom:.0001pt'><b>&nbsp;</b></p>
<p style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;margin-left:1.0cm;
margin-bottom:.0001pt'><b><a href="index.htm" title=index.htm>[ Back to Main
Index ]</a></b></p>
<p style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;margin-left:1.0cm;
margin-bottom:.0001pt'><b>&nbsp;</b></p>
<div style='margin-left:1.0cm;margin-right:1.0cm'>
<hr />
</div>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:1.0cm;margin-bottom:.0001pt;text-align:left'><b><span
style='font-size:8.0pt'>HISTORY:</span></b><span style='font-size:8.0pt'>&nbsp;&nbsp;
Page created 21/10/2001 </span></p>
<p align=left style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:1.0cm;margin-bottom:.0001pt;text-align:left'><span
style='font-size:8.0pt'>21/10/2001 Cyrus 1 &amp; NAD3020 schematics added</span></p>
<p class=MsoNormal style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:1.0cm;margin-bottom:.0001pt'><span style='font-size:8.0pt'>08/11/2001
Sugden A48-II Schematic added</span></p>
<p class=MsoNormal style='margin-top:0cm;margin-right:1.0cm;margin-bottom:0cm;
margin-left:1.0cm;margin-bottom:.0001pt'><span style='font-size:8.0pt'>17/08/2003
Format changed to access gif files directly</span></p>
</div>
</body>
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