Writeup for D's Signpost from NDIAS Automotive/IoT CTF 2026. Five overlapping transmissions at 915 MHz hide Morse hints, an FM voice hint, an AX.25/APRS password, and a DQPSK-encoded password-protected ZIP.
Writeup for Quantum Message from EHAX CTF 2026. A forensic audio challenge analyzing high-speed custom DTMF-style symbol transmission and extracting the encoded decimal streams.
