Befaco MAIN PCB User manual

SAMPLING MODULATOR V1.6.1_UPGRADE - ASSEMBLY GUIDE – Rev. Apr 19
THANKS FOR CHOOSING ONE OF OUR KITS!
Thi manual ha been written taking into account the common i ue that we often find people experience in our
work hop . The order in which the component are placed on the board i meant to make a embly a ea y a po ible.
Some tep are not obviou , o even if you're an experienced DIYer plea e read the tep thoroughly before tarting.
If thi i your fir t project, plea e read thi article before you tart a embling the kit:
www.befaco.org/howto/
GOOD LUCK!
MAIN PCB (THE SMALL ONE)
OPEN MAIN BOARD BAG A
RESISTORS
Qty Value Code Name on PCB
11 10k Brown, black, black, red, brown R5, R10, R11, R14, R18, R25, R26,
R28, R32, R34, R38
7 100k Brown, black, black, orange, brown R7, R15, R23, R31, R33, R35, R36
3 20k Red, black, black, red, brown R13, R17, R29
2 1K Brown, black, black, brown, brown R2, R21
2 2k2 Red, red, black, brown, brown R19, R20
2 4k7 Yellow, violet, black, brown, brown R24, R30
2 6K2 Blue, red, black, brown, brown R8, R9
1 4.22 Ohm Yellow, red, red, silver, brown R12 (mount in vertical)
2 47k Yellow, violet, black, red, brown R27, R37
195K3 White, green, orange, red, brown R4
1 820 Ohm Gray, red, black, black, brown R39
1 2k Red, black, black, brown, brown R40
1 2k7 Red, violet, black, brown, brown R3
1 330K Orange, orange, black, orange, brown R22
1 820k Gray, red, black, orange, brown R16
DIODES
Solder the diode respecting the p larity. Black or white line on the diode mu t be in the ame place a white line
on diode ymbol on PCB ilk creen.
Qty Value Name on PCB
2 1N5817 (Black) D22, D23
2 1N4148 D1, D2
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SAMPLING MODULATOR V1.6.1_UPGRADE - ASSEMBLY GUIDE – Rev. Apr 19
FERRITES
Solder the two ferrite bead by u ing a recycled re i tor leg pa ed through each ferrite and proceed a if it were a
re i tor. Ferrite bead don't have polarity.
Qty Name on PCB
2 FERRITE+, FERRITE-
OPEN ICs BAG
ICs
Fir t place the s ckets (taking care to orientate them properly – the notch or dot on one end of the IC hould match
the image on the ilk creen) and older them into their correct po ition .
Next place the IC in their re pective ocket (again taking note of their orientation – the notch or dot on the top of
the IC mu t match that of the ocket and ilk creen).
Qty Value Name on PCB
3 TL072 IC1, IC2, IC3
1 LM393 IC4
1 LF398 IC5
OPEN MAIN BOARD BAG B
CAPACITORS
Identifying capacitor can be quite tricky. Code tated are indicative, plea e take a look at thi guide for help
identifying capacitor : http://www.wikihow.com/Read-a-Capacitor
Qty Value Code Name on PCB
7 100n 104 C1, C4, C7, C9, C11, C15, C16
3 2n2 222 C6, C8, C12
1 10n 103 C2
1 1n 102 C5
1 47p 47p C10
1 100p 101 C3
ELECTROLYTIC CAPACITORS
Value are written on the ide of the capacitor. Mind their polarity (The long leg of the capacitor i the po itive (+)).
Qty Value Code Name on PCB
2 10 Fµ10 FµC13, C14
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SAMPLING MODULATOR V1.6.1_UPGRADE - ASSEMBLY GUIDE – Rev. Apr 19
TRANSISTORS
Be ure they are orientated correctly. The curved and flat ide of the ilk creen outline of the tran i tor on the PCB
mu t match that of the tran i tor’ body.
Qty Value Name on PCB
6 2n3904 T1, Q1, Q2, Q3, Q4, Q5
TRIMMER
Solder the 10k trimmer at “V/Oct” where the ilk creen indicate on the PCB, with the crew facing out from from the
edge of the PCB.
MALE PIN HEADERS
Place and older the Male Pin Header on the ilk creen ide where the ilk creen indicate (it i the horter pin that
you are oldering).
POWER CONNECTOR
Solder the power connector at “EPOWER”. The mall arrow on the connector mu t be on the ide with the thick white
line.
Buen trabaj ! Y u’ve already made it quite far thr ugh the build. H w are y ur f cus and
energy levels? D y u think a 15 minute break w uld better prepare y u f r the rest f the
build? Maybe y u c uld call s me ne y u haven’t talked t in a while r d s mething
useful like debate p litics n faceb k r l k at vide s f cats being jerks?
CONTROL PCB
OPEN CONTROL BOARD BAG A
RESISTORS
Qty Value Code Name on PCB
8 18k Brown, gray, black, red, brown R103, R104, R105, R106, R107, R108, R109, R111
3 100K Brown, black, black, orange, brown R100, R114, R115
2 3k9 Orange, white, black, brown, brown R102, R110
1 1M Brown, black, black, yellow, brown R112
1 180k Brown, gray, black, orange, brown R113
1 1K Brown, black, black, brown, brown R101
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SAMPLING MODULATOR V1.6.1_UPGRADE - ASSEMBLY GUIDE – Rev. Apr 19
DIODES
Solder the diode bserving their p larity. The black or white line on the diode mu t match with the white line on
the diode ymbol on the PCB ilk creen.
Qty Value Name on PCB
1 1N4148 D100
CAPACITORS
Qty Value Code Name on PCB
1 100n 104 C100
FEMALE PIN HEADERS
Place and older the female Pin Header on the ilk creen ide where the ilk creen indicate
FRONT PANEL COMPONENTS MOUNTING TIPS:
Now we will proceed to mount the jack , potentiometer , witche and LED . Thi part of the a embly i CRITICAL.
Plea e take your time and read the following in truction carefully. The e component mu t NOT be oldered until they
are placed on the PCB and fully attached to the front panel.
There are two rea on for thi :
•The height of the panel component are not all the ame. Becau e of thi , if not attached properly before
oldering, they will not tay properly eated again t the panel. Thi might cau e mechanical tre reducing
their life expectancy and in the wor t ca e cau e them to break.
•The econd rea on i that it i very difficult to align the component to the hole if the panel i not po itioned
prior to oldering. In the ca e of the LED , they are almo t impo ible to et to the correct height without
reference to the front panel.
OPEN CONTROL BOARD BAG B
SPACERS
Secure the pacer onto the CONTROL PCB (through the hole with the ilver outline) with the main body of the pacer
on the component ide, and the nut on the oppo ite.
LEDs
Place the LED onto the PCB minding, their polarity, but d n't s lder them until the front panel i in place. Thi i
the only way to older them in the right po ition.
The long leg i the po itive and the hort the negative. On the PCB the quare pad indicate the negative ide and
there i a + ymbol to indicate the po itive.
Qty Name on PCB
8 D3, D4, D5, D6, D7, D8, D9, D10
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SAMPLING MODULATOR V1.6.1_UPGRADE - ASSEMBLY GUIDE – Rev. Apr 19
MINI-JACKS
Place all the mini-jack onto the PCB en uring they are on the ilk creen ide, but d n't s lder yet.
Cauti n: the witch nut and the jack nut look the ame, but they are not equally ized and will not fit in each
other ' thread, o make ure to keep them eparate!
POTENTIOMETERS
Now place potentiometer on the PCB but... d n't s lder them.
Do not put them all the way down. They mu t be flat again t the panel and leveled with minijack . Al o, you could
hort circuit pin underneath!!
Qty Type Name on PCB
2 Single (3pin) 100K FINE, COARSE
SWITCHES
Place the toggle witche but d n't s lder them until they are ecured to the front panel. Thi way it' ea ier to
older them in the right po ition.
You will know which one i the two and tree po ition by flipping the witch and noting how many po ition it can re t
at.
Qty Type Name on PCB
1 Single two po ition SW1
8 Single Three po ition SW2, SW3, SW4, SW5, SW6, SW7, SW8, SW9
FRONT PANEL
Attach the fr nt panel adju ting the part one by one if nece ary until they fit. At thi point a pair of fine tweezer
can be helpful.
To fini h:
- Secure the part to the panel in thi order: A) Mini-jacks B) Switches and C) P ts
- En uring all of the above part are flu h with the panel then you can finally s lder them!
- Next, adju t the LEDs o that they are flu h with the panel and older them.
- Connect the main PCB to the c ntr l PCB u ing the pin header and by threading the M3 crew through
the main PCB and ecuring it to the pacer. The main PCB hould be orientated o that the component ide i facing
toward the front panel.
- Put the kn bs on the potentiometer and the caps on all witche .
- Connect the p wer ribb n cable: The red wire (-12V) on the power ribbon cable corre pond to pin number
one on the male power connector. The number one pin i indicated with a mall triangle on the male power connector
and a white line on the main PCB. A white or black line (or “-12v”) marked on your power bu normally indicate the
corre ponding pin.
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SAMPLING MODULATOR V1.6.1_UPGRADE - ASSEMBLY GUIDE – Rev. Apr 19
CALIBRATION
Mo t of the feature of the ampling modulator will work correctly after a embly, but in order to achieve preci e
V/Oct tracking you hould adju t the V/Oct trimmer carefully u ing the following method:
You will need:
- A decent multimeter.
- A mall flat-head crew driver (or better yet a trimming tool).
- An electronic in trument tuner.
- A calibrated DC voltage ource.
If you do not have a DC voltage ource to hand you can create one with a multi-turn potentiometer ( et up a voltage
divider) u ing the following method
•Connect Leg 1 to a po itive voltage ource, Leg 3 to negative (or ground) and u e Leg 2 a your voltage
ource output. NOTE: Alway mea ure your voltage when they are connected to CV IN.
The calibration proce i an iteration of ucce ive approximation a follow :
•Connect a tuner to the CLOCK OUTPUT or to Pin 1 of IC3, then:
1 - Move the RATE and FINE RATE pot on the module until you have an E2 on your tuner.
2 - Add 3.000 Volt to the V/Oct CV input u ing your voltage ource. Mea ure thi voltage once it ha been
connected to the module to en ure it i 3.000 (3 volt )
3 - Adju t RATE until you have E5 (+/- 0 cent ) on your tuner.
4 - Di connect the voltage ource from CV IN3 and adju t the V/Oct trimmer until you reach E2 + 0 cent
5 – Go back through tep 2 - 4 until there i no need of adju tment after adding the 3.000 volt .
You can al o u e a decent MIDI to CV interface or any device that can end pitch CV accurately a the voltage
ource. Ju t move within three octave to make ure it' tracking properly.
ENJOY YOUR NEW BEFACO MODULE!
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SAMPLING MODULATOR V1.6.1_UPGRADE - ASSEMBLY GUIDE – Rev. Apr 19
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