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“Baby Will” Valve Junior Conversion
Version 4
Build Manual
22 September 2009
5 of 36
Table of Contents
1.
Introduction ............................................................................................................................. 2
2.
Electrical Shock Warning ........................................................................................................ 4
3.
Disclaimer of Liability .............................................................................................................. 4
4.
Project Overview..................................................................................................................... 6
4.1
Here’s what you’ll need: ................................................................................................. 6
4.1.1
Parts: ..................................................................................................................... 6
4.1.2
Tools: ..................................................................................................................... 6
4.1.3
Supplies: ................................................................................................................ 6
5.
Let’s get started…................................................................................................................... 7
5.1
Remove the EVJ chassis ............................................................................................... 7
5.2
Remove the EVJ’s Stock Components .......................................................................... 8
5.2.1
Remove the Tubes and Tube Retainers ............................................................... 8
5.2.2
Remove the Output Transformer........................................................................... 8
5.2.3
Clean Up the Power Transformer........................................................................ 10
5.2.4
Remove the Volume Potentiometer .................................................................... 11
5.2.5
Remove the Stock EVJ Circuit Board.................................................................. 11
6.
Prepare the Chassis ............................................................................................................. 13
6.1
Layout and Drill ............................................................................................................ 13
6.1.1
Layout the Drill Plans........................................................................................... 13
6.1.2
Drilling the Chassis.............................................................................................. 14
7.
The Baby Will........................................................................................................................ 16
7.1
Assemble the Baby Will Circuit Board.......................................................................... 16
7.1.1
Tube Sockets....................................................................................................... 16
7.1.2
PCB Standoffs ..................................................................................................... 17
7.1.3
The Power Grid ................................................................................................... 17
7.1.4
Signal Path and Cathode Resistors .................................................................... 19
7.1.5
Sag Resistor ........................................................................................................ 19
7.1.6
Signal Path and Cathode Capacitors .................................................................. 20
7.1.7
Hum Balance ....................................................................................................... 20
7.1.8
Filter Capacitors and Ground Wire...................................................................... 21
7.1.9
Jumper Wires ...................................................................................................... 21
7.1.10
Input Jack Hookup............................................................................................... 22
7.1.11
Volume and Tone Controls.................................................................................. 25
8.
Putting it All Together............................................................................................................ 26
8.1
Install the New Components ........................................................................................ 26
8.1.1
The New Output Transformer.............................................................................. 26
8.1.2
The Baby Will PCB and Tube Hardware ............................................................. 28
8.1.3
Hookup the Leads to the Baby Will ..................................................................... 29
9.
Turn on the Power ................................................................................................................ 31
9.1
Check Your Work ......................................................................................................... 31
9.1.1
Take a Break ....................................................................................................... 31
9.1.2
Visual Inspection ................................................................................................. 31
9.2
Power Up without Tubes .............................................................................................. 32
9.2.1
The First Power Up.............................................................................................. 32
9.3
Power Up with Tubes ................................................................................................... 33
9.3
Power Up with Tubes ................................................................................................... 34
9.3.1
The Real Test ...................................................................................................... 34
11.
Finish Things Up............................................................................................................... 35
11.
Finish Things Up............................................................................................................... 36
11.1
Re-Assemble the Amp ................................................................................................. 36
