<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE eagle SYSTEM "eagle.dtd">
<eagle version="7.7.0">
<drawing>
<board>
<plain>
<wire x1="0" y1="0" x2="50" y2="0" width="0" layer="20"/>
<wire x1="50" y1="0" x2="50" y2="59.5" width="0" layer="20"/>
<wire x1="50" y1="59.5" x2="0" y2="59.5" width="0" layer="20"/>
<wire x1="0" y1="59.5" x2="0" y2="0" width="0" layer="20"/>
<text>Alt Gain</text>
<text>Gain</text>
<text>3</text>
<text>2</text>
<text>3</text>
<text>2</text>
<text>G</text>
<hole x="47.25" y="3.75" drill="3.5"/>
<hole x="2.75" y="3.75" drill="3.5"/>
<hole x="47.25" y="50" drill="3.5"/>
<hole x="2.75" y="50" drill="3.5"/>
<text>FETs Eddy</text>
<text>v1.4 Jan 2017 (Jon Patton)</text>
</plain>
<libraries>
<library name="capacitors-elec">
<description>&lt;b&gt;Capacitors, Polar Electrolytic, Radial &lt;/b&gt;
&lt;ul&gt;
&lt;li&gt;large value capacitors: .22 - 470uF (uF = µF = mF)
&lt;li&gt;often used in power supply filters
&lt;/ul&gt;</description>
<packages>
<package name="125_050_1">
<description>&lt;b&gt;8mm diameter, 3.5mm lead spacing, 0.2" pad spacing&lt;/b&gt;</description>
</package>
<package name="063_025">
<description>&lt;b&gt;6.3mm diameter, 2.5 mm lead spacing, 0.1" pad spacing&lt;/b&gt;</description>
</package>
</packages>
</library>
<library name="capacitors-film">
<description>&lt;b&gt;Capacitors, Ceramic&lt;/b&gt;
&lt;ul&gt;
&lt;li&gt;very small capacitances: 1 - 1000pF
&lt;/ul&gt;</description>
<packages>
<package name="BOX_BIG">
</package>
<package name="BOX_MED">
</package>
</packages>
</library>
<library name="transistors">
<description>&lt;b&gt;Transistors&lt;/b&gt;
&lt;ul&gt;
&lt;li&gt;small signal amps (e.g., 2N508x)
&lt;li&gt;switching transistors (e.g., 2N2222, 2N390x)
&lt;li&gt;JFETs (e.g., J201, 2N3819, 2N5457)
&lt;li&gt;MOSFETs (e.g., BS170, BS250)
&lt;li&gt;mostly copied from Eagle libraries
&lt;/ul&gt;</description>
<packages>
<package name="TO220_ALT">
</package>
<package name="TO92-">
</package>
</packages>
</library>
<library name="1776_SUPPLY">
<description>&lt;b&gt;Supply&lt;/b&gt;
&lt;ul&gt;
&lt;li&gt;input, output, ground, and power supply.  
&lt;li&gt;these are used on a schematic for placeholders and on a board for pads for off-board components like jacks.
&lt;/ul&gt;</description>
<packages>
<package name="OCTOGON">
<description>&lt;b&gt;Octogonal Pad&lt;/b&gt;
&lt;ul&gt;&lt;li&gt;drill diameter 0.7 mm&lt;/li&gt;&lt;/ul&gt;</description>
</package>
<package name="SQUARE">
<description>&lt;b&gt;Square Pad&lt;/b&gt;
&lt;ul&gt;&lt;li&gt;drill diameter 0.7 mm&lt;/li&gt;&lt;/ul&gt;</description>
</package>
</packages>
</library>
<library name="potentiometers">
<packages>
<package name="2262_TRIM">
<description>&lt;b&gt;Potentiometer&lt;/b&gt;&lt;p&gt;
1/4" on-board trim potentiometer</description>
</package>
</packages>
</library>
<library name="resistors">
<description>&lt;b&gt;Resistors&lt;/b&gt;
&lt;ul&gt;
&lt;li&gt;6mm long -- the size of 1/4 watt resistors
&lt;li&gt; all resistor values have the same size package; you choose the value of resistance 
&lt;/ul&gt;</description>
<packages>
<package name="R0207/4">
<description>&lt;b&gt;RESISTOR&lt;/b&gt;&lt;br&gt;
&lt;br&gt;
length: 6mm&lt;br&gt;
format: 0.1" (perfboard)&lt;br&gt;
spacing: 4 holes

&lt;p&gt;This length resistor applies to 1/4 watt metal film.</description>
</package>
<package name="R0207/3">
<description>&lt;b&gt;RESISTOR&lt;/b&gt;&lt;br&gt;
&lt;br&gt;
length: 6mm&lt;br&gt;
format: 0.1" (perfboard)&lt;br&gt;
spacing: 3 holes

&lt;p&gt;This length resistor applies to 1/4 watt metal film.</description>
</package>
</packages>
</library>
<library name="diodes">
<packages>
<package name="LED3MM">
<description>&lt;B&gt;LED&lt;/B&gt;&lt;p&gt;
3 mm, round</description>
</package>
<package name="DO41-3">
<description>&lt;b&gt;DO-41 0.3" pad spacing&lt;/b&gt;</description>
</package>
</packages>
</library>
<library name="jacks">
<packages>
<package name="DC_REVERSED">
</package>
</packages>
</library>
</libraries>
<attributes>
</attributes>
<variantdefs>
</variantdefs>
<elements>
<element name="C2" library="capacitors-elec" package="125_050_1" value="470uF"/>
<element name="Q1" library="transistors" package="TO92-" value="2SK30A">
<attribute name="NAME"/>
</element>
<element name="C1" library="capacitors-film" package="BOX_BIG" value="220nF"/>
<element name="R11" library="resistors" package="R0207/3" value="6k8"/>
<element name="R12" library="resistors" package="R0207/3" value="6k8"/>
<element name="R3" library="resistors" package="R0207/3" value="xΩ"/>
<element name="R2" library="resistors" package="R0207/3" value="22K"/>
<element name="I3" library="1776_SUPPLY" package="OCTOGON" value="">
<attribute name="NAME"/>
</element>
<element name="I2" library="1776_SUPPLY" package="OCTOGON" value="">
<attribute name="NAME"/>
</element>
<element name="R1" library="resistors" package="R0207/3" value="1M"/>
<element name="Q3" library="transistors" package="TO92-" value="2SK30A">
<attribute name="NAME"/>
</element>
<element name="C3" library="capacitors-film" package="BOX_BIG" value="220nF"/>
<element name="R7" library="resistors" package="R0207/3" value="2k2"/>
<element name="R6" library="resistors" package="R0207/3" value="22K"/>
<element name="R8" library="resistors" package="R0207/3" value="22K"/>
<element name="R9" library="resistors" package="R0207/4" value="100R 2W"/>
<element name="R5" library="resistors" package="R0207/3" value="1M"/>
<element name="OXP+" library="1776_SUPPLY" package="OCTOGON" value="">
<attribute name="NAME"/>
</element>
<element name="R10" library="resistors" package="R0207/3" value="470Ω"/>
<element name="C5" library="capacitors-elec" package="125_050_1" value="470uF"/>
<element name="PH.P" library="1776_SUPPLY" package="OCTOGON" value="">
<attribute name="NAME"/>
</element>
<element name="TIP" library="1776_SUPPLY" package="OCTOGON" value="">
<attribute name="NAME"/>
</element>
<element name="C4" library="capacitors-elec" package="063_025" value="47uF"/>
<element name="G" library="1776_SUPPLY" package="OCTOGON" value=""/>
<element name="R4" library="resistors" package="R0207/3" value="1k5"/>
<element name="BIAS1" library="potentiometers" package="2262_TRIM" value="250K"/>
<element name="BIAS2" library="potentiometers" package="2262_TRIM" value="250K"/>
<element name="C10" library="capacitors-elec" package="063_025" value="47uF"/>
<element name="C11" library="capacitors-elec" package="063_025" value="47uF"/>
<element name="W2" library="1776_SUPPLY" package="OCTOGON" value=""/>
<element name="W1" library="1776_SUPPLY" package="OCTOGON" value=""/>
<element name="Q6" library="transistors" package="TO220_ALT" value="">
<attribute name="NAME"/>
</element>
<element name="R14" library="resistors" package="R0207/3" value="10K"/>
<element name="D1" library="diodes" package="DO41-3" value="24-30V"/>
<element name="R13" library="resistors" package="R0207/4" value="xΩ 2-5W"/>
<element name="C7" library="capacitors-elec" package="063_025" value="47uF"/>
<element name="C6" library="capacitors-film" package="BOX_MED" value="220nF"/>
<element name="B" library="1776_SUPPLY" package="OCTOGON" value=""/>
<element name="B2" library="1776_SUPPLY" package="OCTOGON" value=""/>
<element name="B3" library="1776_SUPPLY" package="OCTOGON" value=""/>
<element name="B4" library="1776_SUPPLY" package="OCTOGON" value=""/>
<element name="B5" library="1776_SUPPLY" package="OCTOGON" value=""/>
<element name="D2" library="diodes" package="LED3MM" value="Green"/>
<element name="D3" library="diodes" package="DO41-3" value="1N4007"/>
<element name="48V" library="jacks" package="DC_REVERSED" value="DC_MONO">
<attribute name="NAME"/>
<attribute name="NAME"/>
</element>
<element name="AG2" library="1776_SUPPLY" package="OCTOGON" value=""/>
<element name="AG3" library="1776_SUPPLY" package="OCTOGON" value=""/>
<element name="C8" library="capacitors-elec" package="125_050_1" value="470uF"/>
<element name="C9" library="capacitors-elec" package="125_050_1" value="470uF"/>
<element name="G3" library="1776_SUPPLY" package="OCTOGON" value=""/>
<element name="G2" library="1776_SUPPLY" package="OCTOGON" value=""/>
<element name="+48V" library="1776_SUPPLY" package="SQUARE" value="">
<attribute name="NAME"/>
</element>
<element name="Q2" library="transistors" package="TO92-" value="2N3904"/>
<element name="Q4" library="transistors" package="TO92-" value="2N3904"/>
<element name="Q5" library="transistors" package="TO92-" value="2N3904"/>
</elements>
<signals>
<signal name="N$2">
<contactref element="Q1" pad="3"/>
<contactref element="R3" pad="2"/>
</signal>
<signal name="N$5">
<contactref element="R3" pad="1"/>
<contactref element="C2" pad="+"/>
<contactref element="R4" pad="2"/>
</signal>
<signal name="GND">
<contactref element="R9" pad="1"/>
<contactref element="C5" pad="-"/>
<contactref element="R4" pad="1"/>
<contactref element="BIAS1" pad="1"/>
<contactref element="C10" pad="-"/>
<contactref element="C11" pad="-"/>
<contactref element="BIAS2" pad="1"/>
<contactref element="G" pad="1"/>
<contactref element="D1" pad="A"/>
<contactref element="C7" pad="-"/>
<contactref element="C6" pad="1"/>
<contactref element="48V" pad="S"/>
<contactref element="AG2" pad="1"/>
<contactref element="C8" pad="-"/>
<contactref element="R7" pad="1"/>
<contactref element="C9" pad="-"/>
<contactref element="D2" pad="K"/>
</signal>
<signal name="N$11">
<contactref element="R12" pad="2"/>
<contactref element="R10" pad="2"/>
<contactref element="R11" pad="2"/>
<contactref element="C5" pad="+"/>
</signal>
<signal name="N$13">
<contactref element="R11" pad="1"/>
<contactref element="I2" pad="1"/>
</signal>
<signal name="N$14">
<contactref element="R12" pad="1"/>
<contactref element="I3" pad="1"/>
</signal>
<signal name="N$8">
<contactref element="Q3" pad="1"/>
<contactref element="R6" pad="1"/>
<contactref element="B4" pad="1"/>
<contactref element="Q4" pad="2"/>
</signal>
<signal name="N$15">
<contactref element="Q3" pad="3"/>
<contactref element="R7" pad="2"/>
</signal>
<signal name="N$16">
<contactref element="R8" pad="1"/>
<contactref element="B5" pad="1"/>
<contactref element="D3" pad="A"/>
<contactref element="Q5" pad="2"/>
</signal>
<signal name="N$17">
<contactref element="R9" pad="2"/>
<contactref element="Q5" pad="3"/>
</signal>
<signal name="N$20">
<contactref element="Q3" pad="2"/>
<contactref element="C3" pad="1"/>
<contactref element="R5" pad="1"/>
<contactref element="B3" pad="1"/>
</signal>
<signal name="N$21">
<contactref element="C4" pad="+"/>
<contactref element="Q4" pad="3"/>
<contactref element="Q5" pad="1"/>
</signal>
<signal name="N$23">
<contactref element="C1" pad="2"/>
<contactref element="TIP" pad="1"/>
</signal>
<signal name="N$9">
<contactref element="Q1" pad="2"/>
<contactref element="C1" pad="1"/>
<contactref element="R1" pad="1"/>
<contactref element="B" pad="1"/>
</signal>
<signal name="N$10">
<contactref element="R13" pad="1"/>
<contactref element="48V" pad="T"/>
<contactref element="+48V" pad="1"/>
</signal>
<signal name="N$12">
<contactref element="OXP+" pad="1"/>
<contactref element="C4" pad="-"/>
</signal>
<signal name="N$19">
<contactref element="Q1" pad="1"/>
<contactref element="R2" pad="1"/>
<contactref element="B2" pad="1"/>
<contactref element="Q2" pad="2"/>
</signal>
<signal name="VA">
<contactref element="R8" pad="2"/>
<contactref element="R2" pad="2"/>
<contactref element="R6" pad="2"/>
<contactref element="BIAS2" pad="3"/>
<contactref element="BIAS1" pad="3"/>
<contactref element="Q6" pad="1"/>
<contactref element="C9" pad="+"/>
<contactref element="Q2" pad="1"/>
<contactref element="Q4" pad="1"/>
</signal>
<signal name="N$6">
<contactref element="R1" pad="2"/>
<contactref element="BIAS1" pad="2"/>
<contactref element="C10" pad="+"/>
<contactref element="W1" pad="1"/>
</signal>
<signal name="N$24">
<contactref element="R5" pad="2"/>
<contactref element="BIAS2" pad="2"/>
<contactref element="C11" pad="+"/>
<contactref element="W2" pad="1"/>
</signal>
<signal name="N$25">
<contactref element="R14" pad="1"/>
<contactref element="D1" pad="C"/>
<contactref element="Q6" pad="3"/>
<contactref element="C8" pad="+"/>
</signal>
<signal name="N$7">
<contactref element="R14" pad="2"/>
<contactref element="R13" pad="2"/>
<contactref element="Q6" pad="2"/>
<contactref element="C7" pad="+"/>
<contactref element="C6" pad="2"/>
</signal>
<signal name="N$4">
<contactref element="C2" pad="-"/>
<contactref element="AG3" pad="1"/>
</signal>
<signal name="N$18">
<contactref element="C3" pad="2"/>
<contactref element="G2" pad="1"/>
</signal>
<signal name="N$22">
<contactref element="R10" pad="1"/>
<contactref element="PH.P" pad="1"/>
</signal>
<signal name="N$3">
<contactref element="D2" pad="A"/>
<contactref element="D3" pad="C"/>
</signal>
<signal name="N$1">
<contactref element="G3" pad="1"/>
<contactref element="Q2" pad="3"/>
</signal>
</signals>
</board>
</drawing>
</eagle>
