Diagram bluetooth receiver module audio circuit xs couple wire understand symbols arduino connect don explains following found also online Bluetooth module 5v Bluetooth speaker project
Android Bluetooth Remote Controlled Relay Project using 8051/89c2051
Bc04 class 1 bluetoothmodule
Android bluetooth remote controlled relay project using 8051/89c2051
Bluetooth speaker project .
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![bluetooth - I don't understand a couple of symbols on this diagram](https://i2.wp.com/i.stack.imgur.com/0Llsh.png)
![Android Bluetooth Remote Controlled Relay Project using 8051/89c2051](https://i2.wp.com/www.hobbyprojects.com/bluetooth-device-control/images/android-controlled-relay-using-89C2051-bluetooth-module-large.jpg)
![BC04 Class 1 BluetoothModule](https://i2.wp.com/www.oemblue.com/images/BC04Class1 BluetoothModule_clip_image002.gif)
![Bluetooth Speaker Project - tataylino.com](https://i2.wp.com/tataylino.com/wp-content/uploads/2015/11/alma01_s.png)
![Bluetooth Speaker Project - tataylino.com](https://i2.wp.com/tataylino.com/wp-content/uploads/2015/11/alma01_sch.png)