black Magic MkII
PNP fuzz with built in voltage Inverter
Resistors Capacitors Transistors R1 100k C1 10n Q1‐Q3 Ge PNP R2 R3 10k 100k C2 C3 4u7 100n Diodes R4 R5 100k 470R C4 C5 4u7 10n Integrated Circuits R6 R7 CLR 8k2 1M5 4k7 C6 C7 C8 C9 47uF 100uF 10uF 10uF Pots D1,D2 IC1 1 1N4001 TC1044SCPA Level A100K Attack B1K Notes:
The black Magic MKii is a modern take on the classic sola sound tone bender mkii fuzz.
An onboard voltage inverter has been added in front of the circuit to allow the user the
option to power it along with their other pedals using a one-spot (tm) style power
supply. The power section has also been modified to filter out unwanted noise and to
provide reverse polarity protection.
This PCB was designed for right angle 9mm alpha potentiometers and a 1590a enclosure.
The idea was to allow the builder the option of PCB mounting the pots in a 1590a!
Although it takes some planning and careful drilling it can be accomplished by an
experienced builder. There is a drill template at the end of this build doc that should
work (I’ve used it myself). I would still recommend that the builder take it slowly and
verify before drilling. One small mistake can have large consequences down the line!
The first obstacle is fitting the 1/4 inch jacks between the PCB and the footswitch. I am in
the process of trying some new jacks, but as of date, I have only made this work with
standard open frame mono jacks. Simply bend the solder terminals 90 degrees as
pictured below and you should not have any issues. Do not attempt to make it perfect.
The more you bend, the weaker the metal becomes. I’m a bit of a perfectionist and had
to learn the hard way!
2 Another obstacle is fitting the 9vdc jack at the top of the enclosure. There are two
ways I have discovered to make this work. First, you can simply bend the terminals on
the DC jack (pictured above). This will easily work if you use a small DC jack such as the
lumbergs found here. The other option would be to mount the electrolytic caps on the
bottom side of the PCB between the 9mm PCB mounted jacks (pictured below). I
personally like this choice more as It makes for a cleaner build! If you go this route I
would need to use low profile electrolytic caps like these.
The final requirement for the 1590a PCB mount build is to cut off both metal tabs on the
bottom side of the potentiometers (pictured below). A sharp pair of dikes will easily cut
the tabs but it is even easier to bend the tabs back and forth until they snap off. This
step is made to prevent shorting the circuit (I revised my layout and overlooked the
tabs when placing parts).
3 The led indicator is also included on this pcb along with a current limiting resistor (labeled
clr on the pcb). The “sw” pad at the bottom of the pcb connects to 3pdt footswitch lug
that you would normally connect to the led cathode. If you do not plan to mount your
led to the PCB you can just leave off the clr and wire an led as normal.
4 Links:
Alpha 9mm right angle potentiometers:
Small Bear:
http://www.smallbearelec.com/servlet/Detail?no=1139
Mammoth Electronics:
http://www.mammothelectronics.com/category-s/159.htm
Tayda:
http://www.taydaelectronics.com/1k-ohm-linear-taper-potentiometer-roundshaft-pcb-9mm.html
http://www.taydaelectronics.com/100k-ohm-logarithmic-taper-potentiometerround-shaft-pcb-9mm.html
Lumberg 9VDC Jacks:
DIY guitar pedals:
http://www.diyguitarpedals.com.au/shop/index.php?main_page=product_info&cPa
th=15&products_id=130
Small Bear:
http://www.smallbearelec.com/servlet/Detail?no=1362
Low profile Electrolytic Capacitors:
DIY guitar pedals:
http://www.diyguitarpedals.com.au/shop/index.php?main_page=index&cPath=12_14
Mouser:
4u7: http://www.mouser.com/ProductDetail/Panasonic/ECEA1EKS4R7/?qs=sGAEpiMZZMtZ1n0r9vR22RyzzjEKRzqKRu3e7DH7EtM%3d
10uF: http://www.mouser.com/ProductDetail/Panasonic/ECEA1EKA100/?qs=sGAEpiMZZMtZ1n0r9vR22ZJeXBnf%252bMH2xe2xaDqrj9g%3d
47uF: http://www.mouser.com/ProductDetail/Panasonic/ECEA1EKA470/?qs=sGAEpiMZZMtZ1n0r9vR22ZJeXBnf%252bMH2NmmkVovpnpc%3d
100uF: http://www.mouser.com/ProductDetail/Panasonic/ECEA1CKA101/?qs=sGAEpiMZZMtZ1n0r9vR22ZJeXBnf%252bMH2zqk0CFC1sZg%3d
5 Schematic
6