PA0FRI Active Antenna Redux - The final version?

I recently worked on a PA0FRI Active Antenna design with fast BFR93A / BFR106 transistors. Design 3D render: Schematic: Previous Next     / [pdf] View the PDF file here. Simulation Results ...

February 12, 2026 · 1 min · 81 words · Dhiru Kholia

A Sustainable Radio Design?

Future radio receiver design ideas (from Ismo, Pete and other folks): Antenna ➔ (BPF) ➔ BFR93A based pre-amp from mcHF project ➔ MC1496 (Mixer) ➔ 455 kHz IF ➔ Ceramic filter SMD (HCI) ➔ 'IF amplifier' (20-40 dB gain?) ➔ Overclocked Pico 2's ADC (3+ MSPS) ➔ Digital down-conversion and processing in digital domain ➔ Expose the processed audio samples over USB (Pico 2 acts as a sound card). Benefits: This enables reception of SSB and CW signals! The 455 kHz IF with digital processing gives us the best of both analog selectivity (ceramic filter) and digital flexibility. ...

October 17, 2025 · 1 min · 205 words · Dhiru Kholia