Intro: Real Mc Tube ( Stompbox Guitar Preamp)
This i real Mc tube guitar stompbox that cointain tube 12ax7 that sound superb...for me
based on Fred Nachbaur work and Tone pad, feel free to see th pdf file that they build
WARNING! - Please Read this Information Carefully:
The project described in these pages utilizes POTENTIALLY FATAL HIGH VOLTAGES. If you are in any way unfamiliar with high voltage circuits or are uncomfortable working around high voltages,
PLEASE DO NOT RISK YOUR LIFE BY BUILDING THEM. Seek help from a competent technician before building any unfamiliar electronics circuit. While efforts are made to ensure accuracy of these
circuits, no guarantee is provided, of any kind!
USE AT YOUR OWN RISK: I EXPRESSLY DISCLAIM ALL LIABILITY FOR INJURY OR
PROPERTY DAMAGE RESULTING FROM THIS INFORMATION! ALL INFORMATION IS PROVIDED 'AS-IS' AND WITHOUT WARRANTY OF ANY KIND.
Step 1: Electronic Part
You must make pcb form tonepad that contain real mac tube part. It has 2 pcb first PCB for Power supply (PS) and signal. I print the PDF file and make pcb in local shop tht can make pcb from printed form, you can use another way that suit to you.(etching etc)
From the schematic the first thing to do are make power supplay unit it easy because two transformator combined together to make 12v and 120V ac voltage ( see shematic for more detail) and pcb make it dc voltage so you have to check (with multimeter) both voltage.
please be carefull it contain high voltage ( you can change with anoter tube transformator also but it will cost you more)
the transormator are dual non Center tap (CT) 500mA output input are 220 v (in Indonesia) and output you can connect to 9 v tap.
and output check are 12v for tube heater.
Idont add standby switch but to make safe i add fuse just in case.
tube that i use are not 12ax7 i use( 12at7 or 12BH7 ) because that all in my stock, i also try 12 ax7 but both of them sound better for me.
Step 2: The Stomp Box
It contain only two knobs , 1 input, 1 output jack and ac adapter for your wall 220 v wall adapter , the chasing must fit two transformmer it has
Step 3: The Sound Check
I tried this stomp box with a CORA GM200C guitar apms made in indonesia amplifier with solidstate 200Watt
This is my arrange ment instrument
Guitar->> Mctube->> high input>> amps
please see this
sorry for low light ..