MJK Macro Oscillator User manual

Build Guide
Macro Oscillator in 5U (MOTM)
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Build Guide:!
Macro Oscillator for 5U modular synthesizer
Format: MOTM!
Version: v2a
Introduction
This module is an 5U adaption based on the
famous Eurorack module "Plaits" invented by Émilie
Gillet, the successor to the popular "Braids"
module:
https://www.martinjankoehler.com/synthesizers/
synth-macro-oscillator-in-5u/
This document describes the assembly of the
ported module.
License information
•PCB, Panel & Build Guide: !
CC-by-SA-3.0 Martin Köhler
•Schematics & Firmware: !
CC-by-SA-3.0 Émilie Gillet
https://mutable-instruments.net/modules/plaits/
open_source/

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Macro Oscillator in 5U (MOTM)
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Table of Contents
Introduction!1"
License information!1"
Table of Contents!2"
Bill of Materials (1 / 2)!3"
Bill of Materials (2 / 2)!4"
PCB overview and recommendations!5"
Soldering the Main Board!6"
1. Part A – Water Washable Flux!6"
1.1.SMT parts (back side)!6"
1.2.Front side!8"
1.3.Back side!8"
2. Separate PCB parts!9"
3. Prepare and Solder Cables!11"
4. Front panel: hex nuts!12"
5. Buttons!12"
6. LEDs and screws!13"
7. Potentiometers!14"
8. Jack board!16"
Tests and Calibration!18

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Macro Oscillator in 5U (MOTM)
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Bill of Materials (1 / 2)
Macro Oscillator / 5U edition !
by martinjankoehler.com
Format: MOTM
PCB v2
BOM v2b
CC-by-SA-3.0 Martin Jan Köhler
CC-by-SA-3.0 Émilie Gillet
Index
Qty
Description
Specs
Value
Package
References
C6 C8 C10 C11 C12 C17 C18
C23 C27 C28 C32 C34 C36
C37 C44 C45 C51 C52 C53
19
Capacitor, ceramic
>= 25V, X5R
100n
SMT
0805
Kemet C0805C104J5RACTU
C29, C31
2
Capacitor, ceramic
>= 25V, X5R
2.2u
SMT
0805
Kemet CC0805KKX7R8225
D3
1
BAT54S diode
SMT
SOT23
NEXPERIA BAT54S.215
U2
1
TLC59281DBQ 16ch LED driver
SMT
TSSOP24
Texas Instruments TLC59281DBQR
U3
1
LD2981ABU33 LDO regulator
3.3V
SMT
SOT89-3
ST LD2981ABU33TR
U5
1
PCM5100APW Audio DAC
SMT
SSOP20
Texas Instruments PCM5100APWR
Rled1 (green, left button)
1
Resistor
<= 1%, >= 200mW
68R
THT
TE Connectivity / Neohm LR1F68R
Rled2 (red, right button)
1
Resistor
<= 1%, >= 200mW
75R
THT
TE Connectivity / Neohm LR1F75R
R46, R47
2
Resistor
<= 1%, >= 200mW
1.0k
THT
Welwyn Components / TT Electronics
MFR4-1K0FI
R11, R12
2
Resistor
<=1%, 100mW
2.2k
THT
TE Connectivity / Neohm LR1F2K2
R37
1
Resistor
<= 1%, >= 200mW
5.6k
THT
Welwyn Components / TT Electronics
MFR4-5K6FI
R3, R16, R21, R45, R48, R49,
R50, R51
8
Resistor
<=1%, 100mW
10k
THT
Welwyn Components / TT Electronics
MFR4-10KFI
R19, R32, R35
3
Resistor
<=1%, 100mW
20k
THT
TE Connectivity / Neohm LR1F20K
R18, R20, R22, R28, R31, R34
6
Resistor
<=1%, 100mW
33k
THT
TE Connectivity / Neohm LR1F33K
R17
1
Resistor
<=1%, 100mW
56k
THT
Welwyn Components / TT Electronics
MFR4-56KFI
R13, R14, R15, R24, R38,
R39, R40, R41
8
Resistor
<=1%, 100mW
100k
THT
Welwyn Components / TT Electronics
MFR4-100KFI
R26
1
Resistor
<=1%, 100mW
110k
THT
TE Connectivity / Neohm LR1F110K
R23, R33, R36
3
Resistor
<=1%, 100mW
120k
THT
TE Connectivity / Neohm LR1F120K
R29
1
Resistor
<=1%, 100mW
140k
THT
Yageo MF0207FTE52-140K
R25, R27, R30
3
Resistor
<=1%, 100mW
200k
THT
TE Connectivity / Neohm LR1F200K
L1, L2, L3, L4, L5
5
EMI Filter Bead
>= 1k ohm, 300mA
THT
MURATA BL01RN1A1F1J
C50
1
Capacitor, ceramic
>= 25V, X6S
1u
THT 5mm
5mm radial
KEMET C333C105K5R5TA
C1, C2, C13
3
Capacitor, ceramic
>= 25V, X5R
22u
THT 5mm
5mm radial
TDK FG24X5R1E226MRT6
C38, C42, C43, C46
4
Capacitor, ceramic
>= 25V, C0G, <= 5%
100p
THT 5mm
5mm radial
TDK FG28C0G1H101JNT06
C33, C35, C39, C40, C41,
C47, C48, C49
8
Capacitor, ceramic
>= 25V, C0G, <= 5%
1n
THT 5mm
5mm radial
TDK FG28C0G1H102JNT06
U8
1
IC Socket DIP-8
THT
DIP-8
AliExpress
U6, U7
2
IC Socket DIP-14
THT
DIP-14
AliExpress
U4
1
IC Socket DIP-40
THT
DIP-40
AliExpress
Power MOTM
1
MTA-156 4-way Header
THT
MTA-156
MOLEX MX-26-60-4040
Audio Outputs
2
MTA-156 4-way Header
THT
MTA-100
Molex 538-22-23-2041
LED/Switches
1
MTA-100 7-way header
THT
MTA-100
Normalization
1
MTA-100 5-way header
THT
MTA-100
Molex 538-22-23-2051
Control Voltages
1
MTA-100 8-way header
THT
MTA-100
MOLEX 022232081 A-6373-08A222
CP3, CP7, CP16, CP22, CP30
5
Capacitor, electrolytic
>= 16V
10u
THT 5mm
5mm radial
Panasonic EEUFR1H100
CP4, CP5
2
Capacitor, electrolytic
>= 35V
22u
THT 5mm
5mm radial
Panasonic EEUFR1H220
D1, D2
2
1N5819 diode
THT
DO41
DIODES INCORPORATED 1N5819-T
D4
1
LM4040 Shunt Vref
C grade (0.5%, 100ppm)
10V
THT
TO92
Texas Instruments LM4040BIZ-10.0/NOPB

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Macro Oscillator in 5U (MOTM)
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Bill of Materials (2 / 2)
An XLS version of the BOM is available over at:
https://www.martinjankoehler.com/synthesizers/synth-macro-oscillator-in-5u/
Macro Oscillator / 5U edition !
by martinjankoehler.com
Format: MOTM
PCB v2
BOM v2b
CC-by-SA-3.0 Martin Jan Köhler
CC-by-SA-3.0 Émilie Gillet
Index
Qty
Description
Specs
Package
References
LED1, LED2, LED3, LED4, LED5,
LED6, LED7, LED8
8
LED 3mm red/green common anode
THT
T-1 (3 mm)
Lumex SSL-LX3059IGW-CA
Jgate1, Jtrig1, Jharmonics1,
Jmodel1, Jfm1 Jmorph1 Jtimbre1,
JoutL1 JoutR1, Jvoct1
10
Mono 1/4“ jack PCB Mounted, Switched
THT
AMPHENOL ACJM-MV-2S
Audio Outputs
2
MTA-100 4-way Connector (KK for Coax)
-
MTA-100
Molex 22-01-2047
Crimp Terminals
8
KK Crimp Terminals
-
MTA-100
Molex 08-50-0114
LED/Switches
1
MTA-100 7-way Connector (IDC or KK)
-
MTA-100
Normalization
1
MTA-100 5-way Connector (IDC or KK)
-
MTA-100
Control Voltages
1
MTA-100 8-way Connector (IDC or KK)
-
MTA-100
U1
1
DC-DC converter R-78E3.3-0.5
3.3V, 500mA
THT
Recom R-78E3.3-0.5
U6, U7
2
MCP6004 quad op-amp R2R IO
THT
DIP-14
Microchip MCP6004-I/P
U8
1
TL072 dual op-amp
THT
DIP-8
Texas Instruments TL072ACP
RVfreq1 RVfreqatt1
RVharmonics1 RVmorph1
RVmorphatt1 RVtimbre1
RVtimbreatt1
7
10k linear pot, 16mm Alpha, angled
THT
Alpha 16mm 10k linear
SW1
1
Illuminated Tactile Switch, Red
THT
Highly PB61303BL-1
SW2
1
Illuminated Tactile Switch, Green
THT
Highly PB61303BL-3
AWG 22 wire different colors (for
all signal cables except audio)
RG174AU coax wire for audio
Panel
1
PCB
1
MCU Daughterboard
1
M3 x 11mm hex nuts
5
M3 x 8mm screws, Black, ISO
7380
5
M3 Washers, Black, DIN 125 3,2
9
M3 x 8mm screws, ISO 7380F,
black
4

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PCB overview and recommendations
The PCB contains 3 parts that will be interconnected using MTA-100:
1. main board
2. push button and LED board
3. jack board
I recommend not to break out the three parts of the PCB at this point, that’s nicer to solder IMHO.
Using 2 kinds of soldering wire is recommended:
1. 0,4 mm solder wire with Kester 331 water soluable flux core.!
This is corrosive, which is a good thing as it will eat through any component oxide layer. After
washing drying you should get a perfect looking shiny solder joints.!
VERIFY: Make sure to thoroughly wash the PCB with warm/hot tap water after every couple of
hours.
2. 0,6mm solder wire with no clean flux core for the parts that should not better not be washed
(like potentiometers, etc…)

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Soldering the Main Board
1. Part A – Water Washable Flux
Start with the back side (opposed to the front side which is oriented towards front panel).
1.1. SMT parts (back side)
Start with soldering the SMT ICs U2 and U5.
NOTE: PLEASE use extreme care!
Should this goes wrong, there is no point in continuing.
It’s important to take care not to destroy the PCB pads. It’s a 4-layer PCB and mistakes can
not always be MacGyver’ed in every case. Correct only using hot air or if you use solder wick,
use very narrow ones suited for SMT.
Recommended steps:
1. Place IC and align with an ESD pin
2. VERIFY: silkscreen dot marking pin 1 is aligned with the chip and all pads are aligned
correctly
3. Solder the pin 1 at the dot
4. VERIFY: alignment of pads/pins
5. Solder the pin diagonally on the other side
6. VERIFY: alignment of pads/pins
7. Apply flux
8. Add tiny amounts of solder (if you use too much, you risk bridging pins)
9. Apply flux
10. Use hot air gun to reflow
11. VERIFY: there are no shorts between using the continuity testing function of your
multimeter
OK! You did it! Awesome!
From now on, it’s a piece of cake.
Continue with the remaining back side SMT parts :
1. D3, U3, 0805 SMT Caps).
2. VERIFY: there are no undesired shorts against the
schematics using the continuity testing function of
your multimeter

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1.3. Front side
We’ll leave the front side as-is until later when the user interface elements (potentiometers, LEDs, push
buttons) will be fitted.
1.4. Back side
Populate the PCB according to the large
photograph on the next page.
For axial parts (resistors, diodes, ferrite
beads) a wire bending utiilty can come in handy.
Recommended order:
1. Resistors
2. THT diodes
3. Ferrite beads
4. Radial MLCCs (be sure to use
C0G according where specified)
5. IC sockets
6. MTA sockets
7. Pin Headers
8. Voltage reference (D4)
9. DC-DC converter (U1)
10. Electrolytics
NOTES:
•I recommend leaving out the main board MTA headers (Switches, Normalization, Control
Voltages), and directly soldering the wires on the main board side.
•The distance between resistors and screws on the push button board is too tight.
Therefore make sure to bend Rled1, Rled2 away to prevent contact with the screws.

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2. Separate PCB parts
Use a fine side cutter to separate PCB !
into the 3 parts / boards by cutting the little
bridges between the mouse bites.

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3. Prepare and Solder Cables
From now on, no clean solder is used.
Solder according to the motherboard to photos on the next page.
VERIFY: use pin number next to the MTA footprint to match the pinout on both sides of the cables.
Type
Qty
Pins
Length
Mother Board
Connection
Daughter Board
Connection
Normalization
AWG 22 multi
strand drilled
5
5P
6 cm
Directly soldered
according to PIN 1
alignment
MTA-100 "
(KK or IDC)
Control
Voltage
AWG 22 multi
strand non-
drilled
8
8P
8 cm
Directly soldered
according to PIN 1
alignment
MTA-100 "
(KK or IDC)
Switches/
LEDs
AWG 22 multi
strand non-
drilled
7
7P
13 cm
Directly soldered
according to PIN 1
alignment
MTA-100 "
(KK or IDC)
Audio
Coax RG174U
2
4P
4 cm
MTA-100 (KK)
MTA-100 (KK)

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4. Front panel: hex nuts
Fit the five hex nuts to the back side front panel to secure the button/LED board.
5. Buttons
Solder the push buttons to the LED/button PCB.

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6. LEDs and screws
Fit the LEDs through the
footprints on the front side of
the PCB.
VERIFY: Match the orientation
according to the picture
(shorted lead goes through the
left-most hole).
Put the front panel on top and
turn over the sandwich.
Skrew down the two of the
screws (MH2 and MH5), then
check that the knobs do not
touch the holes in the front
panel, but can be pressed
smoothly before you screw
down the rest and re-check.
VERIFY: The knobs do not
touch the holes in the front
panel, but can be pressed smoothly.
Use your fingers to align the
LEDs so that they all fit equally
into the LED holes.
Solder one leg each, then
double check they’re all in their
holes, else reflow and correct.
Then clip and solder all the
remaining legs.
VERIFY: All LEDs are equally
and fully through their holes

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7. Potentiometers
Using the pliers, break off the little tabs of the
potentiometers.
For securing the potentiometer nuts, a tool is
recommended that does not scratch the front
panel. So do not use a regular wrench, but a hex
key tool as in the picture.
10mm is needed for the Alpha potentiometers.
Now flip the PCB again so you can see the
potentiometers on the silk screen on top.
Place the PCB on an open cubic box somewhat
smaller than the PCB. This will make it easy to lift it up.
Place the 7 potentiometers according to the silk screen image and
slide the Panel on top of the potentiometers.
Carefully lift up the sandwich, without allowing the potentiometers
to fall out of position,
and press your finger against the middle of the PCB to ensure
this.
Place the smooth side of the Alpha washers towards the panel
and lock the potentiometers with the nuts first by finger, than with
the hex key.
VERIFY that they are centered before tightening them down.

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8. Jack board
Place the jacks through the jack
board.
Then slide the front panel over and
carefully use pliers to align them to fit
through the mounting holes.
Hold the sandwich in place and flip it
around.
Then pin the jacks down in place with
a dab of solder on just one pin.
Place the washers (smooth side
towards the panel) and tighten down
the nuts with a 12mm hex tool.
Start with the middle (FM, V/OCT),
then work your way towards the
edges.
VERIFY: to conform to MJK’s OCD, make sure to align
the hex nuts with one corner facing top ;-)
The backside of the finished modules should look
somewhat like the photo on the next page.

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Tests and Calibration
Set your lab power supply to +15V (current limit 70mA) and -15V (current limit 15mA)
and turn it on and verify that the current limit is not reached (which could mean that there are shorts),
and that no parts are getting hot or magic smoke escapes.
After programming the push buttons should cycle through the LEDs, it’s normal that the LEDs do
strange things at this point before calibration.
Follow the „Calibration Procedure“ from the official manual:
https://mutable-instruments.net/modules/plaits/manual/
1. Disconnect all CV inputs.
2. Connect the note CV output of a well-calibrated keyboard interface or MIDI-CV converter to
the V/OCT input. Leave all the other CV inputs unpatched.
3. Press both buttons (A). The first LED slowly blinks in green.
4. Send a voltage of 1.000V to the V/OCT input.
5. Press any button. The first LED now blinks in orange.
6. Send a voltage of 3.000V to the V/OCT input.
7. Press any button.
The module should work by now.
In case of issues there’s a thread on muffwiggler:
https://www.muffwiggler.com/forum/viewtopic.php?t=216177