navigationGo.pngQuick Navigation
allprojects32.pngAll projects

favoriteStar32.pngTop projects
Alan numitron clock
Clapclap 2313/1386
SNES Pi Webserver
USB Volume/USB toys
Smokey amp
Laser cutter
ardReveil v3
SNES Arcade cabinet
Game boy projects
Home Presence Detector


navigationMail.pngContact me

3flags.pngWho's Alan?

Rand Nerd Tut
Datasheet Lib
Reddit Elec
Carnet du maker (fr)
ATmel blog (defunct)

bc05b bluetooth module



Well, I bought that small BC05B module on eBay some times ago, in those moments of "hmmm I might need that one day". And guess what: I need it now (^_^).

Points of interrest

  • Soldering those tight ass microscoping 0.7mm connectors on the side of the module and taking the decision of never ever again use that kind of modules :) No seriously, it works, it's doable with a bit of time and patience, but it's really not fun.
  • It worked for a morning, quite well even on my Kenwood CLX-70. I used the jack in and also the red/white composite ones at the back, no problem. Then I tried to stuff it inside, steal some power from the stereo (using a LM317 to feed it with 3.7v) and there catastrophe! Sound went from great to awful, to nothing. Now it's out of the beast, and I just can't get any sound from it. Like zero, just static. The Vol+ also does not seem to work, only Vol- and I fear that my stupid module is stuck at Vol=0 (mute) ... bummer!
  • EDIT: it's fixed!! There was an invisible short between VOL+ and BACK pins, and that rendered the VOL+ button inefficient and added a big bunch of noise to the board. Now I have it run next to me for one hours to confirm it's all good in term of power regulation. And since I'm a lazy b*stard, instead of shortening and resoldering the ugly air wires I just placed them nicely and drowned the sh*t of that module in hot snort (^_^)v hehehe.


    Recommended setup (taken from site)

    Bill of materials


    Source code


    The infamous module. Pitch between those pins is very small, it's 0.7mm ! Don't shake while soldering.
    Top view: ugliest air wire soldering, a few buttons (blue=power VREG, red=VOL+, yellow=VOL-)

    Side view: where that S.o.B. of BACK and VOL+ were shorted. Fixed on this shot before I litterally drowned it under hot glue.

    Thought I was joking about being lazy and the mountain of hot snort?


    Helpful sources

  • All one needs to know
  • Inspiration

  • A project that implemented it
  • All content on this site is shared under the MIT licence (do what u want, don't sue me, hat tip appreciated) ~ Formerly known as (AlanFromJapan [2009 - 2019])