ptSolar APRS Tracker
The ptSolar from Project: Traveler is a lightweight, solar-powered APRS tracker designed for high-altitude Pico balloon flights. With a ready-to-fly mass of just 17 grams, it's engineered for long-duration missions—including potential circumnavigation of the globe.
Key Features
- Ultra-Light Design: 17.2g ready-to-fly with included 3D-printed holder.
- Solar-Only Power: No batteries required—ideal for extended flights.
- APRS Compatibility: Transmits on 144.390 MHz (North America) and configurable for other regions.
- Open Source: Firmware and schematics available on GitHub.
Proven Performance
The ptSolar has successfully flown in multiple long-duration missions. Its solar-only design has demonstrated reliable APRS packet transmission across continents.





Requirements
To successfully configure and launch the ptSolar APRS tracker, you'll need the following:
- Amateur Radio License*. A valid FCC Amateur Radio license of at least Technician class is required to legally transmit APRS signals in the U.S.
- Configuration Cable Used to program the tracker with your callsign, transmission frequency, and other flight parameters. Available separately via our eBay store.
- Basic Tools
- Soldering iron and solder – for attaching the transmitter, super capacitor, solar panels, and antenna.
- Small hand tools – optional, for fine adjustments or mounting
- Pico Balloon A lightweight balloon suitable for high-altitude, long-duration flights. Sold separately.
- Lifting Gas Either helium or hydrogen is required to fill the balloon. Ensure proper safety precautions when handling gases.
Ordering a Kit
Tracker kits are available for purchase on the Custom Digital Service's eBay store. The kit contains an entire APRS tracker unit, including the solar panels and takes less than 30 minutes to assemble. The only other thing required is a Configuration Cable (also available in the eBay store), and the Pico balloon (sold separately).
Specification | Value |
---|---|
Mass (Tracker) | 14.7g |
Mass (Ready to Fly**) | 17.2g |
Dimensions (with solar panels) |
174mm x 38mm x 17mm
|
Dimensions (without panels)
| 74mm x 38mm x 17mm
|
Frequency | 144.000MHz - 148.000MHz |
RF Output | 500mW |
* Users are responsible for ensuring compliance with local amateur radio regulations. International users should verify APRS frequency allocations in their region.
** Using the supplied 3D printed holder, and minimal amount of kevlar fishing line. Your exact mass may vary.
ptSolar is intended for experimental and educational use. Flight results may vary depending on environmental conditions and launch parameters.