I have an old music center, which eventually "moved" to the country, but I really like it. Appearance of the apparatus is so-so, but the sound is simply gorgeous! I especially admire his low frequency amplifier.
The music center is in good condition, works great. There is a CD-changer for three discs, two decks, one of which records. But, unfortunately, there is no way to read information from modern media - USB drives and flash memory cards in MicroSD format.
side of which there are slots for connecting USB and microSD memory cards. In addition, the player controls are displayed on the panel and there is a small display. The device also contains an FM tuner. It is powered by 5 volts (although there are also models with a 12 V supply). There are exactly the same models with a Bluetooth module.
After evaluating the size and appearance of the device, I decided to embed the player in my music center. About how I did it, and what came of it, I will tell you today.
Required Tools
For work we need:
Built-in MP3 player 5V;
screwdriver;
soldering iron with solder and flux;
mounting wires;
a tool for creating a slot in a plastic case (vibration cutter);
multimeter;
screwdriver, 2 screws and a 2mm drill.
The sequence of modernization of the music center
For the player to work, you need to connect:
power circuits (to a voltage source of +5 Volts);
output signal circuits (left and right channel).
Since there is an AUX mode in the center, and there are corresponding tulip-shaped connectors on the back panel, I decided to connect the player's output signal circuits to the AUX connectors from the inside.
So, to search for connection points for +5 Volt power circuits and access the inside of the AUX connectors, we remove the side cover of the case.
On the common board of the music center we find three points with the inscription AUX: GND - common, R - right, L - left. We will solder the conclusions of our player GND, RO and OL to them, respectively, common, right, left.
On the loop going from the power supply of the music center to the common board, we are looking for a voltage source of +5 Volts. Since the points on the board are not signed, we find the required voltage by measuring with a multimeter. To do this, we connect one of its probes to the GND contact or to the chassis of the music center, which is connected to ground (GND), with the second probe we check all the wires of the loop. Yes, it is very important to search when the AUX mode is on, since it is in this mode that I am going to listen to the player in the future.
After finding the connection points, I solder all five wires of the player according to the temporary scheme (the sixth output is ANT - I do not use the antenna, since there is an FM tuner in the center). When performing soldering, the music center must be disconnected from the mains. I place the player on the top panel of the music center and plug it into the network without putting back the side cover.
Conclusion
I want to remind you that you can start work of this kind, having a clear idea of \u200b\u200bthe danger of electric shock. It should be remembered that the voltage of a household electrical network of 220 volts is fatal. It is strictly forbidden to connect electrical devices to the network with the covers removed during operation.
Therefore, when manipulating with the plugged in without a cover, you need to exercise increased caution and accuracy without touching the board with your hands. When working with a multimeter, you should not allow the probe to close adjacent pads on the board, which can damage the music center circuit.
As for the 5 V power supply, if for some reason you could not find it, but a voltage of 9 - 15 Volts is available, then you can use another modification of the built-in MP3 player with a 12 V power supply, it just works in this range.
