2 layers40 × 79.6 mm
ESP32 Transmitter and Receiver
hackclub/OnBoard
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48 parts915
2 layers135.7 × 90.1 mm
- Size
- 135.7 × 90.1 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 48
- Nets
- 44
- Pads
- 234
- Tracks, vias
- 270, 26
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 25 Dec 2025
- Updated
- 6 Nov 2026
Overview
Bias is an open-source printed circuit board by hhiroshell, from the hhiroshell/optokbd repository on GitHub, published under the Apache-2.0 licence. It is a 2-layer board of 135.7 × 90.1 mm with 48 parts on 44 nets, routed with 270 tracks and 26 vias.
Its parts include 23 switches, 22 diodes, 2 connectors and 1 IC.
README
README.mdDIY Keyboard "Opto" ⌨
Parts
48| Qty | Value | Footprint | References |
|---|---|---|---|
| 22 | D | Diode_SMD:D_SOD-123 | D1, D2, D3, D10, D11, D12, D13, D14, D15, D16, D17, D18, D19, D20, D21, D22 +6 |
| 22 | SW_Push | kbd_SW:CherryMX_Hotswap_1u | SW1, SW2, SW3, SW10, SW11, SW12, SW13, SW14, SW15, SW16, SW17, SW18, SW19, SW20, SW21, SW22 +6 |
| 1 | Conn_01x02 | kbd_Parts:Battery_2pin | J2 |
| 1 | Micon_BLEMicroPro | kbd_Parts:Micon_BMP_7sKB | U1 |
| 1 | SW_Push | kbd_Parts:ResetSW | SW23 |
| 1 | TRRS_MJ-4PP-9 | kbd_Parts:TRRS_MJ-4PP-9 | J1 |
Questions
How big is the Bias PCB?
It measures 135.7 × 90.1 mm and has 2 copper layers, 1.6 mm thick.
What parts does the Bias use?
48 parts. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the Bias KiCad files?
From the hhiroshell/optokbd repository on GitHub, at the commit this page was made from: the board is pcbs/assemble_l/bias.kicad_pcb and its schematic pcbs/assemble_l/bias.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Bias design in my own project?
Its repository publishes it under the Apache-2.0 licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).
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