KV4P HT DIY Guide-Add MagSafe Mount for Android Ham Radio
KV4P HT DIY Guide: Add MagSafe Mount for Android Ham Radio
All design files can be found in my github
What is KV4P HT?
KV4P HT is an open-source DIY project that turns an Android phone into a portable ham radio transceiver. It connects hardware and software to enable radio communication directly from your smartphone.
KV4P-HT is currently one of the most popular open-source amateur radio projects. It allows your Android phone to function as a portable handheld transceiver (HT). Depending on the RF module selected, it can operate on either the V-band (144 MHz) or U-band (430 MHz), but not both at the same time.
The official project provides implementations using off-the-shelf development boards, as well as a custom PCB version designed in KiCad. After dedicating time last year to learning KiCad and completing two practical projects, I have become comfortable designing circuits with it.
Why Add a MagSafe Mount?
Adding MagSafe improves usability:
Easier mounting on phone Better portability Cleaner setup Quick attach/detach
Although KV4P-HT does not yet support iOS, many modern Android phones now feature MagSafe-like magnetic attachment. Designing a magnetic version of KV4P-HT would make it much more convenient to attach and detach on the go. Inspired by the sleek MagSafe case from the Meshmastic project, I decided to create my own magnetic enclosure.
Additionally, I found the official KiCad project could be improved in terms of style, organization, and standardization. Therefore, I am refactoring and optimizing it.
Materials and Tools Needed
KV4P HT board MagSafe magnet ring Power components 3D printed case (if any) Tools (soldering iron, etc.)
Main Changes in This Revision:
- Schematic connectivity remains largely unchanged.
- Replaced the USB-to-serial chip from CP2102N to CH340K (the original CP2102N is more expensive and harder to hand-solder).
- Improved the schematic drawing style by using local net labels within pages instead of cross-page or global port connections.
Current Issues:
- The PID of the CH340K is not yet supported by the official Android App (Web App works without any problems).
- The enclosure design is too thick. I plan to switch to a sandwich-style SMA connector to reduce thickness.
- The 3D model lacks a dedicated slot for the ferrite bead, causing it to protrude significantly and affecting the overall appearance.
Common Issues and Fixes
KV4P HT not working? Check wiring Check app config MagSafe not aligned? Adjust ring position Use stronger magnets
Who Is This Project For?
Ham radio hobbyists DIY electronics enthusiasts Android tinkerers
Final Thoughts
KV4P HT + MagSafe makes setup cleaner Easy portable radio solution Great DIY project