NOTE
==============
This repo has been cloned with permission from its original author at 
https://git.e1e0.net/brymen_bm869s_ir_cable.git

The modifications I made were to make it work with an attiny84a MCU which I 
happened to have available. The schematic has been updated to reflect this 
as well.
==============

# Brymen 869s Serial cable

BOM:

  * micro controller ATTiny85
  * One infrared diode.
  * One photodiode.
  * 3 resistors (75R 4k7 2k)
  * One NPN BJT (like the 2N2222A)
  * A usb to serial adapter that can provid 5v.

I built it on a perfboard, so no pcb design is provided.

The 3D desigh fits perfectly and leaves 48 x 11 mm (more or less) of
space for the pcb. An STL file can be found at (in case you don't know
how to use FreeCAD):

https://onna.be/files/brymen_cable_attachemnt_v2.stl