Android hates HC-06, but loves HC-05

Hi guys, i'm writing right now to report a strange behavior of the couples Android ---- HC-06 bluetooth and Android ----HC-05 bluetooth.

I've worked on a project that involved bluetooth remote control and so i decided to develop my application on the popular HC-06. I'm quite familiar with that module, AT commands , etc .

Once developed my sketch, i developed an android app to connect and get the trick done from remote. But i noticed that something wasn't working the way it was supposed to. Android ( Xperia SP smartphone, jellybean 4.3) was connecting to the module but only after a few tryouts. then it worked like a charm. So i decided to inspect my android app ( just have basic android programming skills ) but everything was fine. So i checked my module and tried different tricks like resistors on TX,RX line, etc . but nothing changed. Trying to connect to hc-06 several times every time i wanted to get remote control , made me nervous.

Then, just a few days ago , i decided to get an HC-05 module and replace the HC-06. Same wiring, same app, same sketch. Working like a charm from the start. No more problems , no more annoying tryouts, all was just perfect.

So i am here asking : WHY???? i can't find any reason why hc-06 shouldn't work! i thought that the only difference between 05 and 06 was the possibility to change the master-slave mode.

Just to be clear, i tried different hc-06s with same results before getting the hc-05

funksoulbrother: So i am here asking : WHY???? i can't find any reason why hc-06 shouldn't work!

Who knows? but I think it's true - up to a point.

I have three JY-MCU devices, one HC-06 and two HC-05s. All worked OK off a Uno and connected to a Dell laptop. After that, all operations were with the HC-06, simply because I had not connected the LED on the HC-05s, and I had no immediate need for them..

The HC-06 has worked perfectly with laptop and the phone, a Huawei Y210.

While my first cheapo tablet could usually see the HC-06, I never got it to connect and work with it. The main reason why I got the phone was that I had despaired of ever getting the tablet to work. The tablet finally died and I now have a new one. It connects OK with HC-06 but it must have taken tern seconds to pair and I nearly gave up.

I turned out that the original tablet worked just fine with a bluetooth keyboard I had bought for the phone, and I eventually found that it connected fine and worked OK with an HC-05. It still wouldn’t work with the HC-06.

I am still inclined to blame the tablet, but things are clearly not all they might be in the bluetooth world. In short, my HC-06 works fine with laptop, tablet and phone, and is the module I routinely use, but I would always recommend getting an HC-05. They are more versatile than the HC-06, the price difference, if any, is trivial, and they have never been known to give grief.