Labels Milestones
BackAudio Switronic ST-005-G 3.5mm Horizontal Waterproof Stereo Headphones Jack, https://www.technik.com.hk/images/pdf_product/WP3002-PA66-A.pdf audio jack stereo horizontal waterproof 6.35mm (1/4 in) Vertical Jack, 2 Poles (Mono / TS)
- Shielded power inductor http://www.abracon.com/Magnetics/power/ASPI-3012S.pdf Bourns.
- Reflective opto couple photo coupler IR Receiver Vishay.