MothSynth OLED has a 3V power terminal on the back. You can power it with an inexpensive 3V 2x AA (Double A) battery pack commonly available online or purchase MothSynth OLED pre-modded. The battery pack can be glued, or attached with double sided tape (which we do in-house).

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Simply solder the red wire from the battery pack to the + terminal on the back of the MothSynth OLED, and the black wire to the - terminal.