Aion Electronics Halo Fuzz, Руководство пользователя

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4 BIG MUFF PI / HALO FUZZ
Variant: Fire Red Fuzz
A boutique BMP clone from BJFE in Sweden. It’s somewhat close to a Violet Ram’s Head, but take note of the
alternate JFET gain recovery stage.
* For the JFET gain recovery stage , omit R20 and add C101 and R101. JFETs have different pinouts than
bipolar transistors, so an extra pad has been provided to keep you from having to twist the legs around.
Assuming your JFET’s pinout is D-S-G (typical for 2N5485), keep the transistor facing the same direction as
the silkscreen but shift it down by one pad. (The two outer pads are connected.)
** For the JFETs in the first clipping stage , tie together the source and drain. However, make sure to check
the datasheet for your brand of JFET. 2N3819s tend to be D-G-S, different from a 2N5485, but sometimes
different brands have different pinouts. For a D-G-S pinout you will need to tie together the two outer pins
which takes some dexterity. Leave plenty of space around the middle pin so nothing shorts against it!
Capacitors
C1 1uF
C2 (omit)
C3 1uF
C4 100n
C5 470pF
C6 100n
C7 100n
C8 (omit)
C9 1uF
C10 3n9
C11 10n
C12 220n
C13 1uF
C14 100uF
C15 100n
C101 10uF
Resistors, cont.
R18 22k
R19 22k
R20 (omit)
R21 68k
R22 14k7
R23 6k8
R24 100R
R101 2k
Semiconductors
Q1 - Q3 BC550C
Q4 2N5485*
D1 - D2 2N3819**
D3 - D4 1N914
Resistors
R2 33k
R3 100k
R4 470k
R5 100R
R6 15k
R7 470R
R8 8k2
R9 100k
R10 470k
R11 100R
R12 10k
R13 8k2
R14 100k
R15 470k
R16 150R
R17 15k
Additional Part Notes
• For all variants listed above,
the
Sustain
and
Tone
pots are 100kB and
Volume
is 100kA.
• In some of the configurations, capacitors such as C4 and C7 are 1uF. I left space around these so you
can use Panasonic ECQ-V film capacitors . Some others such as WIMA box film will fit as well.
• Values above are assuming the midrange mod is not used . If you do use this mod, you’ll want R18 to
be 2.2k or 3.3k and C10 to be 12n. This may not always sound exactly like the original since many of the
variants get their distinctive sound from the tone section, so it’s advisable to socket R18, R19 and C10
and experiment.
• Potentiometers are Alpha 16mm right-angle PCB mount.
• I recommend using these dust covers / insulators from Small Bear to insulate the back of the pots from
the board and prevent shorts. If you don’t use these, use some electrical tape or cardboard to act as
insulation. The right-angle pots will make direct contact with the solder pads otherwise.