PCB and Schematic:
BOM:
Qty | Value | Device | Package | Description |
|---|---|---|---|---|
| 2 | 100R | Resistor | R0805 | |
| 2 | 100n | Capacitor | C0603 | 0603 PACKAGE! |
| 1 | 10n | Capacitor | C0805 | |
| 1 | 1M | Resistor | R0805 | |
| 2 | 1k | Resistor | R0805 | |
| 4 | 1u | Capacitor | C0805 | |
| 1 | 22k | Resistor | R0805 | |
| 1 | 2k2 | Resistor | R0805 | |
| 2 | A100k | Potentiometer | 9mm vertical snap-in | Alpha / Panasonic style with 6mm built-in knob. |
| 1 | Tile Tail | "Futaba J" power connector | ||
| 2 | M7 / 1n4007 | Diode (Power) | DO214AC | |
| 3 | 3.5mm Jack | THONKICONN | 3.5mm socket for Eurorack modular synths | |
| 1 | TL072 | SO08 | OP AMP |
Assembly:
- Clean the PCB with Isopropyl Alcohol.
- Solder the surface-mount components to the PCB.
- Begin with resistors and capacitors.
- The small unlabelled footprints (0603 size) are 100n capacitors.
- The two large unlabelled footprints near the power header are M7/1n4007 diodes. Make sure the polarity is correct.
- Finally, add the OpAmp, making sure it’s in the correct position (pin 1 is by the large white dot).
- If using hot-air or an oven to solder the surface-mount components then do this now.
- Inspect all of the soldered components for solder bridges between pins and components, especially around the OpAmps.
- Solder the Tile-Tail power lead and 3-pin BP LP header.
- Solder the front components (pot and jacks). It’s a good idea to put the panel on before soldering to make sure they are aligned.
- Again inspect all of the soldered components for solder bridges between pins.
Testing:
Check that there’s no continuity between the red, white, and black wires on the power lead. If there is continuity then for shorts between the components around the power lead and diodes.
Check that there’s no continuity between the both ends of each of the small 0603 capacitors, located near the OpAmp. If there’s continuity then check all of the soldered connections for shorts.
Plug the module in and test all functions.