CubeSat Simulator
Overview
The CubeSat Simulator is a ground-based amateur-radio device that mimics a real CubeSat's radio behavior on the ground, transmitting live telemetry over UHF so operators can practice receiving and decoding satellite signals without an actual satellite. This deep dive covers the full build (boards, power/solar subsystem, RF payload), the RF and systems theory (telemetry framing, modulation modes, link budget, Part 97 envelope), the schematics for all three boards, and step-by-step usage — from powering up to decoding telemetry on a ground station.
Context
The AMSAT CubeSatSim is an open-source educational platform that mimics a real CubeSat's radio behavior on the ground — a working model satellite that transmits authentic telemetry frames over the air in the 70 cm amateur band, enabling ground-station operators to practice tuning, receiving, and decoding satellite signals without waiting for an actual pass overhead. Jeff's deep dive documents the v2.1 hardware (Main/Battery/Solar boards), all six operating modes (APRS/FSK/BPSK/SSTV/CW/Cross-Band-Repeater), and a full machined-aluminum 1U frame build on a Carbide 3D Nomad 3.
