VU GPSDR: RK3399 Touchscreen SBC with GPS-Disciplined SDR
Rockchip RK3399-based touchscreen SBC paired with GPS-disciplined SDR using R860 and RTL2832U, covering 500 kHz–1.766 GHz with PPS-stabilized clocking.
VU GPSDR touchscreen SBC
The Vivid Unit, a palm-sized Rockchip RK3399-based touchscreen SBC, is the prospective market for UUGear’s VU GPSDR, an inexpensive GPS-disciplined SDR expansion board. The Rafael Micro R860 tuner and RTL2832U ADC form the foundation of the VU GPSDR.
This module guarantees high frequency stability and timing accuracy with a high-precision 24 MHz PPS clock produced by the onboard u-blox NEO-M8N GPS module in reference to the Si5351 local oscillator. VU GPSDR becomes a fully functional, portable SDR system with a touchscreen when combined with Vivid Unit and Vivid Unit Extender. The RK3399 CPU, 4GB RAM, and 32GB eMMC storage are features of the Vivid Unit. With a 5.5-inch touch screen, speaker, microphone, Wi-Fi, Bluetooth, and multiple interfaces, this device is small enough to fit in a palm size.
VU GPSDR touchscreen SBC Top and Bottom
VU GPSDR specifications:
- MCU: STM8S003F
- RF:
- Tuner: Rafael Micro R860
- ADC: Realtek RTL2832U
- Frequency Range: 500 kHz to 1.766 GHz
- Bandwidth: Up to 3.2 MHz (2.4 MHz recommended for stability)
- HF Up conversion: An integrated 108 MHz up-converter for amateur/shortwave bands that allow reception below 30 MHz
- Antenna:
- 1x SMA (SDR antenna input); no Bias-Tee
- 1x SMA Output (software-adjustable clock output via Si5351)
- Clocking:
- Local Oscillator: Si5351, disciplined by 24 MHz PPS from u-blox NEO-M8N GPS
- GPS-adjusted clock for long-term frequency accuracy
- 1x onboard GPS antenna connected via IPEX 1st gen connector with 5V Bias-Tee support
- I2C header for u-blox NEO-M8N GPS
- Misc:
- Dual rotary encoders
- 2x push buttons for controls
- GPS fix green LED
- SWD header for STM8 MCU
- Dimension: 210 × 110 × 10 mm
- Weight: 0.065 kg
VU GPSDR Interfaces
GPSDR++, a fork of the open-source SDR++ (v1.2.0) project, is compatible with the VU GPSDR. The company advises turning on GPU acceleration for the Mali-T860 GPU to avoid lag because the RK3399 SoC of the Vivid Unit must manage real-time waterfall displays and demodulation. On the Debian-based OS of the Vivid Unit, installing the gpsdrpp binary and the Vue (Vivid Unit Extender) package is simple using apt.
On the UUGear E-Shop, the VU GPSDR expansion board costs €65.00, or roughly $77.40 USD. It is not a stand-alone device, though; users also need the Vivid Unit (€99.00) and the Vivid Unit Extender (€28.00). Without antennas, a full handheld system costs about €192 (about $205 USD). Additional information can be obtained from the news page.
Images used courtesy of uugear
RTL2832U, why do people still use that crap? It was cool when you could buy a <$10 DVB stick and reuse it as a cheap SDR, but if you’re paying >$100 anyway, then buy something better already.