Hey everyone, wanted to share my latest build! I call it the "Meshphone" - a standalone dual-node Meshtastic device built into a Samsung Galaxy A5 I got on eBay for 20€.

I love my T-Deck, but wanted the full feature set and the ability to run two different configs/protocols simultaneously. Plus, connecting two nodes via USB hub feels cleaner than Bluetooth coupling with potential radio interference.

Build Details

Hardware:

• 2x RAK4630 modules (low power, integrated USB)
• CH334P USB hub IC
• TP4056 + DW01 for battery management
• TI TPS62203DBVT 3.3V buck converter
• 8000mAh 18650 pack (~48h runtime)
• 7 status LEDs with clear PETG light pipes (really proud of how these turned out!) Chassis:
• Samsung Galaxy A5 (battery removed, powered from PCB)
• 3D printed PLA housing for nodes and battery, hot glued in place

Learning Moments

First time working with USB - went with the CH334P because it's cheap and the reference schematic looked straightforward. Differential pair routing was trickier than expected, but USB worked first try! Had to flash the bootloader via SWD to get the USB drive mode working (double-click reset). Also bodged some 5.1k resistors on CC1/CC2 and 5V to VBUS - all fixed in the PCB design though. One quirk: whenever I switch on either node, the hub reconnects completely, so I can't differentiate which node is which USB device. Not sure why, but it's manageable.

Links

Full project on GitHub Happy to answer questions if anyone's interested in building something similar!