I built a light that reacts to radio waves [video]

Original Article ↗ Hacker News Discussion ↗

Overall reaction and artistic impact

  • Strongly positive response: many describe the piece as mesmerizing, beautiful, and conceptually powerful.
  • Several emphasize that it should be viewed primarily as an art project, not just a technical hack.
  • Viewers like how it makes the invisible RF environment tangible and reflective of urban life and proximity.
  • A minority find it visually noisy or potentially irritating, suggesting diffusers or questioning why one would add such a stimulus to a room.

Perception, mapping, and visualization

  • One thread raises the mismatch between dB (log scale) and human light perception, suggesting a linearization + gamma curve and a precomputed lookup table for more intuitive brightness changes.
  • Others imagine RF “cameras” or AR overlays: mapping direction and frequency to colors, seeing RF fields in 3D, and interacting with shielding (e.g., tinfoil).

Technical design: hardware, driving LEDs, RF capture

  • Questions about the many inductors lead to an explanation: each LED channel is constant-current driven to reduce flicker and extend lifespan; inductors are cheap.
  • Some ask if simpler DC + PWM could be used; others accept the current design as fine for an art piece.
  • HackRF is considered overkill and not state-of-the-art; people discuss cheaper SDRs or using chips like nRF52840 as coarse spectrum analyzers, with debate over whether that qualifies as a “waterfall.”
  • Total build cost is reported around $1k; sheet metal fabrication alone is about $200.

Potential applications and variations

  • Ideas include:
    • Walking around with the lamp to see edge cases of RF density.
    • Visualizing Wi-Fi strength in a home or office, perhaps per channel.
    • Hunting down interference sources in audio studios.
    • Detecting SAR satellite scans (noting the need for directional antennas).
    • Audio-output versions that sonify RF, or Morse/steganographic light communication.
    • RF visualization similar to acoustic cameras or night vision.

Video production and creator practice

  • Many praise the editing, narration, and soundtrack; some ask how such polished videos are learned—answer: by watching lots of YouTube and iterating, no formal training.
  • There’s curiosity about sponsorship/brand placement (PCBWay, JLCPCB) and manufacturing choices; both fabs are reported as similarly priced and effective.
  • Some request open-sourcing of code/hardware and an RSS feed for following future works.

Related works and ethical/artistic critiques

  • Commenters reference related RF-visualization projects (Wi-Fi antenna arrays, RF art films, Phillips Hue motion mapping).
  • Another of the creator’s projects (involving scraped poetry on phones) draws criticism for uncredited use of others’ work, seen as a commentary—intended or not—on tech’s treatment of artistic labor.
  • The darknet marketplace artwork spurs speculation about the nature of “illegal data” (e.g., credit cards, PII), framed as part of the piece’s conceptual prompt.