GM LAB PICOSYNTH User manual

PICOSYNTH MONOPHONIC SYNTHESIZER
A DIGITAL SYNTHESIZER PROJECT BASED ON RASPBERRY PI PICO
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Thank you for purcha ing GMLab Pico ynth! Whether you bought the kit
ver ion or the pre-a embled ver ion, plea e refer to thi document for
ba ic information and in truction . If you purcha ed the kit ver ion,
plea e refer to the full ver ion of the guide that you will find online,
here:
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Pico ynth i a ba ic monophonic ynthe izer, ea y to learn and to operate
with all the ection well defined by labeling . It al o have few nice
add-on like the pre et management and a delay ection. Two o cillator
with 5 waveform , L.F.O., filter, envelope, mixer and glide control.
If you are reading thi document or you purcha ed GMLab Pico ynth, you're
likely familiar with ynthe izer , you know how to operate them and how to
generate, manipulate and modify the ound.
No power upply unit i upplied with a KIT purcha e. GMLab Pico ynth
require a 12v DC 500mA minimum power upply in order to correctly
operate. The e are very common and it' likely that you already have one
compatible laying around omewhere. Ju t be ure that the DC male plug i
5.5/2.1 with the po itive in the central pin and the negative in the
external frame of the plug.
You can al o u e a power upply with le voltage (for example 9v) but
plea e don't u e the one for guitar pedal , they are normally with center
negative. You can al o power on your Pico ynth ju t connecting a MICRO-USB
cable into the Ra pberry PI PICO port but we won't ugge t to do thi for
a long period of time. U ing a different power ource that the one
ugge ted (12v DC) won't harm your in trument, unle you connect a power
upply with a voltage higher than 12v; but thi will affect the audio
quality becau e the operational amplifier circuitry u ed in thi project
i de igned around 12v DC for optimal performance.
GMLab Pico ynth i ending out mono audio from the headphone 3.5 jack
plug and the 6.3 jack plug: you can u e them at the ame time.
The MIDI connector of GMLab Pico ynth i a MIDI IN port, there you are
uppo ed to plug a device capable of ending MIDI, typically MIDI NOTE
ON/OFF me age . Plug there your MIDI keyboard, your computer or your
equencer. Pico ynth recognize MIDI data on CH1 and upport MIDI USB.
It recognize CC#1 (modulation wheel) and pitch bender, PC# from 0 to 31
and the "all note off" me age.
With the "+" and "-" pu hbutton you can croll the pre et , pre "STORE"
to ave a pre et (overwrite the exi ting one). To activate the "MANUAL"
mode pre the pu hbutton "+" and "-" at the ame time: when "MANUAL"
mode i engaged, the in trument will ound exactly re pecting the actual
potentiometer' po ition.
If you would like to revert to factory default (original pre et ), pre
and hold "-" with your Pico ynth off and connect the power upply.
GMLAB Pico ynth i old on-line on the web ite www.gmlab.it and on
www.MyRigShop.com by V.M.Connection, an enterpri e ba ed in Italy.
You can get the project file for thi and other GMLab project on our
GitHub account:
http ://github.com/ZioGuido
If you need pare part or blank PCB , ju t let u know.
All trademark mentioned in thi document belong to their re pective
owner and are u ed for reference purpo e only.
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MOUNTING INSTRUCTIONS
Welcome to the mounting in truction heet for the GMLAB Pico ynth
monophonic ynthe izer. To a emble thi kit correctly and et it up to
work properly, a good kill and experience with electronic and computer
i required, plu ome tool and a little bit of patience and attention.
You mu t be able to recognize electronic component , re i tor ,
capacitor , integrated circuit , you mu t be able to older them properly
on the PCB.
Plea e note that we are not re pon ible for in trument not working due to
improper mounting, improper oldering/de oldering of component or part
broken during the mounting proce .
REQUIRED TOOLS
1. Soldering iron, preferably a temperature-controlled 60W iron with a
1,5 ~ 2,5 mm wide tip;
2. Solder tin wire, preferably good quality 0,8 ~ 1 mm diameter;
3. Good quality cutter , plier , crewdriver ;
4. Patience.
PREPARATION
Prepare a clean and tidy urface, with ju t the required tool handy and
make ure you have di charged your body from electro tatic charge by
touching ome metal object that make contact with the floor. Optionally,
wear an ESD wri tband.
WHAT'S IN THE KIT
1x Active Panel bottom PCB
1x Top Panel PCB with premounted SMD component
1x Front panel PCB
1x Rear panel PCB
1x Left panel PCB
1x Right panel PCB
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20x REDCUBE
5x Rubber feet
5x M3x20 M/F HEX pacer
28x M3x5 crew
3x M3 nut
7x Pu h witch
2x 7-Segment di play
30x Tran parent potentiometer
2x 40 pin long female header
4x 20 pin long male header
4x 20 pin hort female header
4x 20 pin hort male header
1x 2 pin hort male header
1x Jumper
1x 6 pin hort male header
1x 9 pin hort male header
1x IC LM4558 or TL072 or TL082
1x IC 6N137
1x IC 7805
1x IC 7809
1x IC 1117
4x IC CD4051 or equivalent
1x IC 74HC165 or equivalent
2x IC 74HC595 or equivalent
1x IC 74HC138 or equivalent
2x Ra pberry PI Pico
1x DAC board
1x Jack TRS 6.3
1x MIDI Connector
1x DC Connector
10x 100nF ceramic capacitor
3x 10uF electrolitic capacitor
2x 1uF capacitor
2x 10kOhm re i tor
2x 220Ohm re i tor
2x 51kOhm re i tor
2x 100kOhm re i tor
3x 1kOhm re i tor
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NOTE ABOUT REDCUBES
Redcube are little component that allow to fix the ide panel of the
ynthe izer without compromi ing the ae thetical end re ult of the
product. They need to be oldered to the bottom and top PCB . The
procedure i not very ea y and we ugge t to do thi operation before
anything el e.
You are required to older 10 piece on the bottom PCB and 10 piece on
the top PCB: 2 piece on every angle plu 2 piece in the middle. Plea e
take a look at the PCB in order to find out where they are located.
Once mounted you will be able to fix the ide panel of your ynthe izer
with the crew to improve the overall tructure and appearance.
The oldering procedure require time: plea e follow our in truction
carefully!
- Locate a REDCUBE pad and place one on it: be ure that the two mall
pin are in ide the 2 mall hole in the pad.
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- You will notice that the pad i a little bit bigger in the in ide area:
that i the place where you have to tart oldering it.
Put the tip of your oldering iron there and tart applying the oldering
tin wire to it: hold them firmly, don't apply the older tin on the pad
before po itioning the REDCUBE, otherwi e it will be difficult then to re-
po ition it again. Plea e don't forget that the area and the redcube will
become very hot!
- You can help your elf in thi operation u ing a tool to firmly hold the
REDCUBE until the older tart melting and attache to the PCB. Don't
move the oldering iron tip!
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- The oldering tip need to heat both the PCB and the REDCUBE before the
tin tart melting. Thi require time, it can be from 10 to 30 econd
depending on the temperature.
- When the older tin tart melting you will ee the tin going everywhere
in the pad and al o underneath the REDCUBE, firmly attaching it to the
PCB. You need a lot of older tin there! Wait until everything i well
covered with the tin and then remove the oldering iron tip gently without
dropping the REDCUBE.
- When the older tin i olid again, the end-re ult hould look like
thi :
- You can now proceed with all 20 piece .
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ACTIVE BOTTOM BOARD
fig. 1
fig. 2
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STEP 1: Let' tart from the electronic . All pa ive component fir t,
tarting from the lowe t till the talle t. Take the re i tor , bend the
terminal 90 degree (if not already bent) and add them to the main PCB in
the correct po ition (check the chematic , ilk creen on the PCB and the
component numbering and value). Do the ame with the capacitor and keep
in mind that electrolitic capacitor do have a polarity.
STEP 2: Let' place and older all the connector (male and female SIL and
DIL header ). Let' tart from the two 2x20 pin female header for the
two Ra pberry PI PICO board .
Then you can proceed with the two 2x20 long male header (the e are u ed
to connect the bottom board to the top board).
Then mount the 2 pin header that i u ed to give or remove power to the
LED underneath the potentiometer in the TOP panel. Adding a jumper the
LED will lit, without the jumper the LED will tay off.
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There are two more header that you need to add: they are tho e for the
DAC board:
Now we are ready for the next tep: integrated circuit and the two
Ra pberry Pi Pico board .
STEP 3: Add the Integrated Circuit . Pay attention not to keep the older
pin for too long, and that all pin have been oldered correctly. Do not
older two or more pin together, each pin i oldered eparately from the
urrounding . Al o pay attention to the direction and polarity. Drawing
on the PCB have a notch on a ide indicating where pin 1 goe . The ame
notch i generally pre ent in the IC it elf, or you'll al o find a mall
dot. Plea e take a clo e look at the code in the integrated circuit
(they all look the ame but they have different code , 4051 i not 595,
6N137 i not the OPAMP!). Thi i a delicate tep, do not make mi take !
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Let' now proceed with the voltage regulator : they are pecial integrated
circuit that, in thi ca e, al o need to be crewed onto the PCB u ing
three 3x5 crew and three M3 nut . Before oldering them, you have to
bend the pin ; plea e al o pay attention on their code , they are three
different one .
Now it' time to add the DAC board: you already oldered two male header ,
one with 9 pin and one with 6 pin . Now plug the DAC board and older it:
plea e note the the board need to touch the pla tic enclo ure of the SIL
header o it will reach the correct height.
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La t thing to do in thi tep i adding the brain of your ynthe izer:
the two Ra pberry PI PICO board . There' a mart way to do thi . Fir t of
all, plug the four 1x20 male header in the four 1x20 female header you
previou ly oldered, like thi :
Then in ert there the two Ra pberry PI PICO board . Plea e note that the
USB connector are facing out ide the board. The two board delivered with
thi kit are pre-programmed and they are labeled "CTRL" and "DSP". Mount
them in the correct po ition!
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STEP 4: Add the MIDI connector, the DC plug and the TRS 6.3 jack and
older them: thi i an ea y procedure.
STEP 5: thi i the la t tep for the bottom board and con i t in
mounting the 5 pla tic Hex pacer and the 5 rubber feet, one for each
corner of the PCB and one in the middle.
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Thi hould be the end-re ult:
Now your bottom board i complete and it hould look a the fig. 1 and
fig. 2 on page 8. Let' now proceed with the top board.
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TOP PANEL BOARD
Fig. 3
Fig. 4
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STEP 6: the top panel board, once mounted, will be the the control urface
of your GMLab Pico ynth, where you will find all the potentiometer ,
di play and the pu hbutton . The potentiometer we elected, have a
tran parent haft, when the jumper in the header named "LED_PWR" in the
bottom board i plugged in, the SMD LED premounted on thi PCB will lit
illuminating the potentiometer' haft. Let' uppo e that you already
oldered the 10 Redcube on thi board ( ee page 5) o let' proceed.
Fir t of all in ert and older the two 1x40 long female header :
Step 7: Now it' time to mount all potentiometer and pu hbutton .
Once again, pay much attention to have them it perfectly on the urface
of the PCB, o they will pa through the panel hole correctly. Our
advice i to keep them with a finger and older ju t one pin, repeat thi
operation for all button and potentiometer , at the end older the re t
of the pin .
Start with the pu hbutton , in ert them in the PCB and older.
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Then in ert the two di play and older them: PLEASE PAY ATTENTION TO THE
DIRECTION! The two dot mu t face toward the bottom. See thi photo.
Then in ert the potentiometer one by one in the board and tart oldering
them.
When you are done, the board hould look a the photo fig. 3 and fig. 4
on page 15.
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STEP 8: In thi tep, you are required to connect together the bottom
board and the top board you ju t finalized. The electric connection
between the two board i made by the two 1x40 pin female and male
header : they need to be connected together. Once the two board are
connected, you will notice that al o the five pla tic Hex pacer will be
in the correct po ition, ju t underneath the corre ponding hole of the
top board. So, ju t crew five M3 crew there.
STEP 9: The very la t tep i mounting the four ide panel for your
Pico ynth. Plea e note that they are all different. You have one for the
rear ide, where you will al o find the labeling for the connection .
One completely black for the left ide, another one for the left ide with
two mall window for the USB connector of the PI PICO board .
The la t one in the front panel with the Pico ynth logo.
They are fixed in the ynthe izer ju t with M3 crew that will go in the
Redcube .
The mounting procedure i over! Good Job!
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