PCB Assembly

PCB Bill of Materials

The following components are required to assemble the PCB:
Item NamePart NumberQuantity
Lantern Soldering JigLPMSJ11
3.5mm Headphone JackPJ-3583-B16
10KΩ ResistorC3854412
68KΩ ResistorC3855411
33KΩ ResistorC3854981
12KΩ ResistorC3854491
180KΩ ResistorC3854601
10uF 25V 4*5 CapacitorC438461
22uF 25V 4*7 CapacitorC438401
40-pin GPIO headerC1698191
The boards sold by Lantern are RoHS compliant and require lead free solder. If you print the boards yourself, just make sure your solder matches your boards.

1. Headphone Jacks

Aligning all 16 headphone jacks is incredibly difficult. It's recommended that you acquire or print a Lantern Soldering Jig to help with aligning the headphone jacks. If you choose to do it without one, balance the board on headphone jacks at the corners first, get them soldered, and then move on to the others.
The labeled side of the PCB goes face down on the jig. Make sure the pins on the headphone jacks match orientation in the photo above. When placing the PCB on the headphone jacks, you might have to jiggle it some to get it to drop on the pins. If it doesn't go on easily, check for any bent pins on the headphone jacks.

2. Resistors

All 6 resistors are clearly labeled on the PCB, so soldering these on should be fairly straightforward. Use the color banding guide below to make sure you have the right resistor for each spot.

3. Capacitors

There are two capacitors, one 10µF and one 22µF. The 10µF goes in C10 and the 22µF goes in C20 (on V1 boards) or C22 (on all new boards). The board has a + sign on the hole for the positive terminal of the capacitor. The longer of the two terminals on the capacitor is positive, the short side has a white stripe with a negative symbol on it. Make sure the positive terminal goes through the positive hole.

4. Analog to Digital Converters

The ADCs must be soldered in the proper orientation. There is a small indentation on the diagram on the board and a small dot on the chip that must align. The pins need to be compressed a little bit to get it to go into the board.

5. 40 Pin Header

To get the board to sit on the header properly, one side of it needs to be propped up so it sits level while you solder.