# ILSE Build Instructions for Revision 1-3
**URL:** https://discourse.chair.audio/t/ilse-build-instructions-for-revision-1-3/107
**Category:** Eurorack
**Created:** [December 9, 2021, 4:28pm UTC](https://discourse.chair.audio/t/ilse-build-instructions-for-revision-1-3/107 "2021-12-09T16:28:33Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@clemens](https://discourse.chair.audio/u/clemens)
#### Post date: [December 9, 2021, 4:28pm UTC](https://discourse.chair.audio/t/ilse-build-instructions-for-revision-1-3/107/1 "2021-12-09T16:28:33Z")
New version (Revision 4): [ILSE Build instructions for Revision 4](https://discourse.chair.audio/t/ilse-build-instructions-for-revision-4/151)
Archive for old version:
### 0. Check Parts
Check if all parts are included in the package. There should be:
- a printed circuit board (PCB)
- a [parts list](https://github.com/clwe/ILSE/blob/main/ilse_rev1.pdf) 📄
- a lot of bags with components
Look at the parts list and check that there is a bag of components for each reference from the parts list. E.g. there should be a bag containing the battery connectors with the reference `BT1,BT2` written on it.
| Item | Qty | Reference(s) | Value |
| --- | --- | --- | --- |
| 1 | 2 | BT1, BT2 | 9 V |
| 2 | 3 | C1, C5, C11 | 1u |
| 3 | 2 | C2, C6 | 0.1u |
| 4 | 2 | C3, C4 | 10n |
| 5 | 1 | C7 | 47n |
| 6 | 2 | C8, C9 | 22n |
| 7 | 1 | C10 | 1n |
| 8 | 2 | C12, C13 | 10u |
| 9 | 2 | D1, D2 | LED Superbright |
| 10 | 5 | J1, J4-J7 | AUDIO / CV JACK |
| 11 | 1 | J2 | EURO RACK POWER |
| 12 | 1 | J3 | CV Input Header Pins |
| 13 | 1 | JP1 | Freq Gate Jumper |
| 14 | 3 | Q1, Q2, Q3 | BC560 |
| 15 | 3 | Q4, Q5, Q6 | BC550 |
| 16 | 3 | R1, R12, R34 | 4k7 |
| 17 | 7 | R2, R21, R23, R24, R25, R29, R37 | 47k |
| 18 | 10 | R3, R4, R8, R20, R26, R27, R28, R36, R38, R39 | 100k |
| 19 | 3 | R5, R6, R16 | 1k |
| 20 | 1 | R7 | 20k |
| 21 | 2 | R9, R35 | 1k |
| 22 | 3 | R10, R11, R22 | 47k |
| 23 | 4 | R13, R14, R17, R18 | 100k |
| 24 | 1 | R15 | 1.5k |
| 25 | 5 | R19, R30, R32, R33, R40 | 10k |
| 26 | 1 | R31 | 2k2 |
| 27 | 1 | RV1 | 5kB |
| 28 | 6 | RV2, RV4, RV5, RV6, RV7, RV8 | 100kB |
| 29 | 1 | RV3 | 500 |
| 30 | 1 | SW1 | Power Switch |
| 31 | 1 | SW2 | LFO to Filter / Freq CV |
| 32 | 1 | SW3 | Resonance L/H |
| 33 | 2 | U1, U2 | TL074 |
Some similar parts are grouped in the same bag to save packaging materials, e.g. `R7`, `R15` and `R31`. Also the bag with 100kOhm resistors will be marked `R3...R39` for brevity but will nonetheless contain 10 resistors.
Always start soldering the components of lowest height first! For the ILSE diy kit these are the resistors. Depending on the parts supply situation at the day you are reading this manual you might need to diverge a little bit from the order of soldering components. E.g. capacitors `C12` and `C13` might be larger then the Euro Rack power connector `J2`. If that is the case, consider soldering them after the Euro Rack power connector.
## A: Back side
Solder the components on the back side of PCB first, since these are the smaller components. Otherwise it might get difficult to solder the resistors in-between the long knobs on the front panel!
### 1. Flat resistors
- So take the bag marked `R1,R12,R34` and find their markings on the back side of the PCB.
- Bend their legs by 90° close to the end of their bodies
- Put their legs through the holes and bend them over on the front side, so they won’t fall out anymore.
- Now you can turn around the board, such that the resistors are facing away from you and you are looking at the bend over legs.
- Solder them: Heat up the pads on the circuit board and the legs of the resistors together, so the solder can melt around it. Once melted, wait a little bit until the solder sucks into the pads. Otherwise you might get loose connections that are hard to debug!
- Now take a wire cutter and cut away the legs after the solder joint.
- Repeat these steps for all flat resistors (items 16,17,18,20,21,24 and 25 on the parts list)!
- Do not solder the standing resistors yet (items 19, `R5,R6,R16`, 22 `R10,R11,R22` and 23 `R13,R14,R17,R18`)
### 3. Opamps
The opamps are marked with the reference `U1,U2`. So these are the big black chips with 14 legs.
- Make sure the orientation is correct: they have a small dip on the left side of the label that is printed on them, this dip is also marked on the PCB, so make sure they align.
- Turn around the board again, so the chips lie on there back and you can see the legs from the other side of the board.
- Solder them!
### 4. Transistors
The transistors are marked `Q1,Q2,Q3` and `Q4,Q5,Q6`. Their orientation matters, so put them such that the printed shapes on the PCB match with their bodies.
### 5. Capacitors
- Solder `C1,C5,C11`,`C3,C4` and `C8,C9`
- then `C2,C6` and `C10`
- then `C12,C13` (in order of ascending height of the parts).
### 6. Standing Resistors
Solder the standing resistors now. These are the following items on the parts list:
- item 19: `R5,R6,R16`,
- item 22: `R10,R11,R22` and
- item 23: `R13,R14,R17,R18`
Now you need to bend them to make them stand on the board:
- Bend only leg of every resistor by 180°, such that is is parallel to the leg on the other side of the resistor.
- Put the unbent leg of the resistors into the hole that has the circuit drawn around them to prevent shorts.
### 7. Euro Rack Power 🔌 Connector
The Euro Rack power connector is marked `J2` on the bag and PCB. Again, orientation matters! There is a small opening both on the body of the connector and on the PCB drawing. Make sure they align.
### 8. Trimmer
The octave scaling trimmer is the highest part on the back side of the PCB, it is marked `RV3`. Solder it now.
### 9. Battery 🔋 Connectors
The battery clips `BT1,BT2` serve as an alternative power source if you haven’t got a Euro Rack power supply yet. You don’t need to solder them, if you plan to put your ILSE in a modular synthesizer rack, since you won’t need batteries and they are just dangling in the case - potentially causing shorts. At least you should **consider isolating the metal contacts** of the battery clips with electrical tape if you solder them and put them inside of a self powered rack.
Yes! Back side is done!!!
## B: Front side
### 1. LEDs 💡
Orientation matters also with LEDs! They have a long and a short leg. The short leg should go where the little dip is on the drawing on the circuit board. Solder them in and cut the legs as you did with the other components, but this time from the front side of the PCB!
### 2. Pin Headers
Solder the pin headers `J3` and the jumper `JP1` to the front side of the PCB so you can access them more easily. But it doesn’t really matter, it rather depends on how you plan to use your ILSE module. E.g. you might want to hide additional circuitry behind the ILSE PCB that connects to the headers. If not, then it is probably better to solder them to the front.
### 3. Audio Jacks
The audio jack inputs `J1`, `J4-J7` go into the rectangular marks were the connections are written out:
- Filter In
- 1V/Oct
- Gate
- Cutoff
- Out
### 4. Switches
The orientation of the switches influence in which state they are on. The switches have manufacture codes printed on them, these should face to the side were the prints on the PCB are (facing upwards).
### 5. Potentiometers
There are two kinds of potentiometers: a single 5kOhm pot (`RV1`) and six 100kOhm potentiometers `RV2`, `RV4-RV8`.
- `RV1` is the global tuning pot and should be placed in the according holes.
- Press them in firmly, they will snap and then sit tightly.
- Solder all five contacts so they get maximum stability.
- Repeat for `RV2`, `RV4-RV8`!
Congratulations: you finished soldering your ILSE module!
---
### Author:  [@fotosdelviaje](https://discourse.chair.audio/u/fotosdelviaje)
#### Post date: [December 5, 2023, 7:20pm UTC](https://discourse.chair.audio/t/ilse-build-instructions-for-revision-1-3/107/2 "2023-12-05T19:20:37Z")
Hey @clemens, I just received my ILSE Rev.1 PCB and I’m sourcing the parts. What type of switches did you use for SW1, SW2 and SW3? I can’t find it in the documentation.
Thank you.
---
### Author:  [@fotosdelviaje](https://discourse.chair.audio/u/fotosdelviaje)
#### Post date: [December 5, 2023, 7:28pm UTC](https://discourse.chair.audio/t/ilse-build-instructions-for-revision-1-3/107/3 "2023-12-05T19:28:36Z")
Looks like they could be [Apem MHPS2285](https://mouser.com/ProductDetail/Apem/MHPS2285)?
---
### Author:  [@clemens](https://discourse.chair.audio/u/clemens)
#### Post date: [December 5, 2023, 9:29pm UTC](https://discourse.chair.audio/t/ilse-build-instructions-for-revision-1-3/107/4 "2023-12-05T21:29:27Z")
Hello @fotosdelviaje,
We used ‎[PVA2EEH4 1.7N V2](https://www.ckswitches.com/media/1343/pva.pdf). You might find other switches which fit the footprints as well, but make sure they have the same switching characteristics.
---
### Author:  [@fotosdelviaje](https://discourse.chair.audio/u/fotosdelviaje)
#### Post date: [December 6, 2023, 1:31am UTC](https://discourse.chair.audio/t/ilse-build-instructions-for-revision-1-3/107/5 "2023-12-06T01:31:11Z")
Thank you @clemens. I’ll try to find an equivalent.