Biography

Born on 20 March 1973. Former CB operator with early experience in HF/11 m propagation and antenna experimentation.
Started amateur radio activity on 20 February 2026 as CR7BYS (CAT3).

Operating from Espinho, near Oporto, grid IN51or, Atlantic coastal environment with favorable VHF/UHF propagation, maritime ducting and low RF noise levels. Typical noise floor ranges between S1–S3 on VHF/UHF and S2–S4 on HF depending on band and time of day.

Current station activity includes APRS, LoRa APRS, SDR monitoring, FT8, WSPR, SSTV, and satellite reception experiments.
Technical interests: SDR-based spectrum analysis, weak-signal digital modes, airband monitoring, LEO satellite reception (NOAA, METEOR, ISS), Meshtastic mesh networking, LoRa APRS, antenna modeling, GPS-disciplined timing systems, and coastal propagation studies.

Equipment

APRS VHF – 144.800 MHz
• Antenna: Diamond X‑50
• Filtering: Diplexer
• Receiver: NooElec Smart v5 SDR
• Host: Raspberry Pi Zero 2 W
• Software: Direwolf (APRS decoder / iGate)

LoRa APRS – 433 MHz
• Antenna: Diamond X‑50
• Hardware: LilyGO T3 v1.6.1
• Filtering: Diplexer
• Mode: LoRa APRS beaconing and monitoring

HF Digital Modes – FT8 / WSPR / SSTV
• Antenna: MLA‑30+ active loop
• Receiver: NooElec Smart v5 SDR
• Timing: GPS Stratum‑1 disciplined clock
• Host: Raspberry Pi 4
• Software: WSJT‑X, OpenWebRX
• Notes: FM filter significantly reduces broadcast interference from strong coastal FM transmitters, improving HF SNR and weak-signal decoding.

SDR & Monitoring Tools
• NooElec Smart v5, Airspy (when applicable)
• NanoVNA for antenna tuning, impedance sweeps and feedline analysis

Other Equipment
• LoRa APRS / Meshtastic: 433/868 MHz modules
• Multiple experimental antennas for wideband SDR reception

Antennas
• Diamond X‑50 (VHF/UHF)
• MLA‑30+ (HF loop)
• DIY VHF eggbeater (under construction)
• Experimental omni-directional LEO satellite antennas
• Various SDR monitoring antenna