BandScand

BandScand is a student‑friendly, hobbyist‑friendly AM and SSB receiver that covers everything from 500 kHz to 150 MHz. Instead of hiding the RF magic inside chips, it exposes the entire signal chain using discrete circuits you can see, probe, and understand. If you’ve ever wanted to learn how real radios work—from antenna to audio—this board is built for you.

At the front end, BandScand uses high‑speed SiGe RF transistors to create a low‑noise amplifier and an active mixer. This mixer design is AC‑coupled, which helps eliminate LO feedthrough and lets you experiment with a real, high‑sensitivity RF front end.

The receiver uses a fixed 1 MHz IF, with the LO for that stage generated directly by the FPGA. The RF tuning LO comes from a discrete VCO running inside a delta‑sigma fractional‑N PLL, giving you smooth tuning across the entire band without complicated analog adjustments.

To help you explore gain control, the IF stage includes a 5‑bit programmable‑gain amplifier with power‑of‑two steps. You can write your own digital AGC loop and watch how it affects real signals. A second 1 MHz demodulator lets you switch between AM and SSB reception, and the final baseband output feeds into a discrete third‑order delta‑sigma ADC for digitization.

BandScand is designed to work with your PC, where you can control every block using simple Python scripts. You can start with the included examples and build your own scanner, spectrum monitor, or automated signal‑logging tool.

Whether you’re a student learning RF for the first time or a hobbyist who wants to go deeper than SDR dongles allow, BandScand gives you a rare chance to explore both analog RF and digital signal processing in one hands‑on platform.