DIY Portable Bluetooth Speaker with LED Display

If you have a small LED screen and want to pair it with a Bluetooth speaker, you can build your own portable Bluetooth speaker with an LED display.

First, open the LED screen enclosure and inspect the internal space. Then, plan where to install each component to ensure everything fits properly.

The entire device supports an external 12V battery for power. You can use a buck converter to step the voltage down to 5V, which also powers an IBM laptop cooling fan to provide adequate heat dissipation and prevent heat buildup during extended operation.

Next, arrange the circuit boards inside the enclosure. Install the Bluetooth decoder board and buck converter in sequence, then connect the radio antenna. Organize and secure all the wiring properly.

However, after completing the assembly, you may notice significant background power noise, which seriously affects the audio quality. After repeated troubleshooting and careful consideration, you can decide to tackle the problem at the power supply stage by adding noise filtering. You can repurpose a laptop power supply for this modification.

Remove the transformer-related section from the power supply and make targeted modifications to the remaining circuitry. You should also adjust the circuit routing as needed.

After these modifications, you should notice a significant reduction in noise. You can further improve the results by adding shielding. Use aluminum plates and aluminum foil to create a shielding barrier and suppress electromagnetic interference.

Once you have completed all the adjustments, test the device to confirm that the unwanted noise has been almost completely eliminated. Finally, close the enclosure and finish your custom-built portable Bluetooth speaker.