bluetoothbox for stereo headphones and speakers
But I didn\'t want to throw away my love for headphones so I thought of making a small box where I could turn the headphones into Bluetooth headphones.
This project shows how to convert all wired headphones or speakers to headphones or Bluetooth wireless speakers and be able to fully charge for at least 6 hours and be able to charge without any complications. .
This is an open hardware project: blueboxbox we need a bit of motivation before we start, look at the pictures and find out what you\'re going to do.
Anyone can complete this project and with just a little bit of electronic skills you can make yourself a unique Bluetooth box.
It only takes 3 days to complete the design and share this project, I hope this project will be of great help to you.
I like Bluetooth, short distance hi-
Technology radio that can transmit all kinds of data.
The Bluetooth headset is great because you can listen to music, play games, or call your friends without a rope.
You can connect this box to any Bluetooth-enabled device, such as a tablet, computer, or almost any mobile phone.
No need for dongle, just $25.
Here are the materials needed to make a Bluetooth box: Tools: Electronics: you can get all the materials on Ebay for a very cheap price.
The audio capacity output directly from the Bluetooth module is too small, so I decided to use the power amplifier module to provide a powerful output signal for speakers and headphones.
The Pam 8403 module meets my requirements with a compact size with 3 w output on both left and right lines.
This is a great choice for mini speakers, and you can also use this module to build your own unique pair of speakers without spending a lot of time on circuit design.
The input signal is connected to the audio output of the Bluetooth module. Here are a few features of module pam 8403: Note: Please make sure the power supply does not exceed 5.
5 V, please do not do reverse polarity for \"and\"\";
Otherwise, it will burn out the board.
This is the most important part of this project: BC-
05B BLK stereo Bluetooth module.
I already got to know Bluetooth a few weeks ago and it was great to know this module.
It is a fully flexible board and you can do a lot of projects with it without any problems.
According to the manufacturer\'s chart, you can build a complete sound system for yourself without a lot of knowledge about them.
The size of the module is completely flexible and I have had the motherboard assembly and success from the first time.
Here are some of the features offered by the manufacturer: BC05-
B The main chip of Bluetooth stereo receiving module is designed with CSR bluecore 5mm.
High integration, small size and other features, only need a small peripheral components to achieve its powerful functions.
A2DP, AVRCP transmission and remote control protocols that can and have any bluetooth source device (
Such as: Bluetooth mobile phone, Bluetooth stereo audio transmission module, Bluetooth adapter, etc. )
High quality stereo audio stream wireless reception is realized, and the player can be controlled remotely. BC05-
B user Bluetooth stereo module with remote control button interface, working status indication interface, stereo audio output interface, microphone input interface.
Features: application area: Great.
About A2DP protocol: the Advanced Audio Distribution Profile is a Bluetooth profile that allows stereo audio to be wirelessly transmitted from A2DP sources (
Usually a phone or computer)
To the A2DP receiver (
A set of Bluetooth headsets or stereo systems).
The AVRCP profiles are also generally supported by these devices in order to allow track selection, etc.
A common misconception is that A2DP is supported for all Bluetooth 2.
0 device, this is not the case, and A2DP is only available on Bluetooth 2.
0 device, this is also incorrect.
A2DP support can exist in older versions of Bluetooth, just not usually supported.
Although this module has been built
In the lithium battery charging circuit, but I still need to use a different battery charging management IC to ensure the safety of this module.
I used 5-to save board area and control flexibility-way switch.
You can see the picture of it on it, this switch is compact in structure, so it is flexible so I can design the board easily.
It has all 10 pins, including four common pins, two pin centers to be pressed down, and four pins in the remaining four directions (
Right, left, up, down).
On this switch, I press center to play/pause, press right to play the next song, press left to play the previous track, press up to increase the volume, and finally press down to reduce the volume.
Next is the headphone jack. I selected a 3.
5mm headphone jack, fully compatible with all types of phone headphones and mini speakers.
There are 5 pins, but I used 4, including 2 pins for GND, one for Righ channel and one for left Channel signal.
If you use a 2-pin stand, you should weld them into two mini speakers.
It works like this: the mini speaker plays music when you don\'t plug the headset into the Bluetooth box.
Otherwise, the speaker stops when you plug in the headset and you hear the music with the headset.
The headphone jack works as a mechanical switch.
If you are interested in rechargeable batteries, you will know tp4056.
The rechargeable battery is completely complicated and can cause damage if you just power the battery with a rechargeable battery, which can cause your battery to explode.
The battery charger should have a complex circuit to manage the current and voltage of each charging cycle.
But don\'t worry, TP4056 provides you with an integrated circuit so you can easily charge the battery without causing any problems.
As a complete module, you can get the TP4056 and you can do other things by simply plugging in the battery.
But I want to redesign the charging circuit to make it fit my motherboard.
Just like the circuit design of the manufacturer in the datasheet, you can see the chart above.
The TP4056 can work with USB and wall adapters, and you can charge up to 1000 mA of your battery.
When the battery is not fully charged, the signal pin on the TP4056 shows you the status of the battery and I connect it to the red LED.
After the battery is fully charged, other signal pins will tell you that the battery status is full and I connect it to the blue LED.
Make sure to connect the correct pin \"and pin \"-
In order not to endanger the safety of the battery.
The power charger is also important and you have to make sure that your power supply is within the manufacturer\'s range.
Learn more in the TP4056 data sheet.
I finished the schematic of the blue tooth box. Simply right-
Click the attached file and select Save link as download file.
You should open this file in Eagle version 6. 4 or higher.
For anyone who does not have the software Eagle installed, there is also a PDF file.
In the schematic I used 3 blue LEDs to indicate that the Bluetooth case is already connected to the transmitter.
I use the 2N3906 PNP transistor to control the LED flashing light from the signal of BLK BC-05 module.
The next step is the printing circuit.
I have split the circuit into two parts, one for USB and headphone jack, and the other for other components.
There are three holes in the positioning of the circuit board.
All components are tightly arranged together to minimize the size of the blue tooth box.
I like to make a printed circuit board at home and it saves costs and is easy to design changes when there is a mistake in the circuit diagram.
Of course, this is not very good.
There are many different ways to make printed circuit boards at home.
You can easily find it on structures, just search.
To optimize the circuit design, I used a two-layer circuit board.
However, you can still use a layer of board because you can route it on the ground floor.
In this step, I show you how to cut the printed circuit board with a crochet cutter PCB copper.
You can get this tool on Ebay for a cheap price.
You can also use the iron ruler, do not use the plastic ruler, it is too soft, you can cut it into a ruler.
Another way is that you can cut the board with a hand saw.
Next is the printed PCB File.
Remember, when you have finished washing the printed circuit board, you should drill holes with drill bit 0.
6mm through holes.
I also designed a case for the Bluetooth box with acrylic resin.
I chose 5mm and 3mm acrylic to make the border and 2mm acrylic to cover the border.
The design of the Corel Draw is simple, but I have to calculate the dimensions carefully to fit the panel board placed in the chassis.
In order to composite the acrylic panel together, I designed more 3 screw holes for each acrylic.
The inner diameter of the hole is 2.
5mm, after laser cutting, put into the screw to rotate.
However, the hole should be 2. 7mm.
Next, I designed a ring that can penetrate the blue LED light, which creates a bright circle when the Bluetooth box is enabled.
To complete this task, I chose the opaque acrylic sheet.
This acrylic looks like only half of the light goes through it and the rest of the light stays in it, so you\'ll see a faint light effect that looks really good.
The light from the LEDs to the acrylic circle has 3 positions.
You can see in the picture the alternate position between the screw holes.
Finally, I designed the lid of the blue tooth box.
There are two covers, one at the top and one at the bottom.
\"Hole\" is where you can control the blue tooth box by pressing the button.
I also put the screw hole and the charging status light.
The words \"USB\" and \"headset\" are the places where you plug in the micro USB port charging and headphone jack.
I also don\'t forget to add names on and below.
The text will be engraved with fully automatic laser.
Here are a few photos of my acrylic sheets after laser cutting in a shop.
The cut is completely accurate, smooth and looks very beautiful.
This is the cover of The Blue Tooth box carved with laser.
Can\'t wait any longer, I tested and assembled the Bluetooth box.
Better than expected. haha.
The printed circuit board is installed in the acrylic coronary artery.
Can\'t be more beautiful :))
I forgot to cut the hole for the headphone jack and micro usb port with the laser cutter because the hole is horizontal and not acrylic so I can\'t see the design of it, which is a big mistake.
So this hole must have been made by hand.
I use a hand saw with a thin thickness that can be cut easily.
Be very careful when doing this because I have broken the Last 3rd of the poles.
Now I sprayed this acrylic case.
Let\'s draw any color you like and I chose red.
I like the combination of red and black acrylic and it looks very beautiful.
When the blue LED light comes on, it looks more beautiful.
I can\'t find any material that goes through the two-story board.
So I decided to do it with a resistor leg.
The resistors are very cheap and I don\'t feel wasted when leaving a few resistors.
After passing through the welding hole, I weld it on the circuit line to protect the hole from oxidation.
Looks much better now.
I welded all the components on the board and finally the battery was welded for testing.
Make sure to connect the correct pin \"and pin \"-
\"In order not to endanger the test, the battery is low: If unfortunately you can\'t start the Bluetooth board, you may have run out of battery.
Start again with a fully charged battery.
If you can\'t start up yet, you should check the board.
I connect the acrylic layer together with hex screws.
The acrylic ring is fragile and fragile. be careful when screwing.
The outside diameter of the screw is 3mm.
Here are the pictures of how the component layout I show fits the case.
The bottom is the panel board, followed by the battery and the board at the top, which includes a micro usb port and headphone jack.
Once fully assembled, it will look like this.
I checked again to make sure the Bluetooth connection is absolutely normal.
A rechargeable battery is required for several hours to use a Bluetooth box.
Plug one end of the USB cable into the USB port of the laptop or charge the phone, plug the other end into the micro USB port, and the red LED lights up indicating that the battery is charging.
After about 1 hour, the blue LED lights up when your battery is fully charged, indicating that you need to disconnect the USB charger cable.
I checked the battery life three times and the Bluetooth box was used continuously for 6 hours after you were fully charged to open with an average volume.
This is correct for predictions, Bluetooth molude energy consumption is very low, it automatically reduces power to save energy when you no longer play music, and wait until you play music again.
So if you forget to turn off the toothbox, you won\'t lose much energy.
Plug in the headset, put it on, enjoy your Bluetooth box, and also connect it to the mini speaker for a larger capacity.
Now you can turn all your audio devices into wireless audio devices.