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Radio Time MachineRF History Explorer

Travel through 130+ years of radio technology. Tap any era to see its signal waveform, hear its sound, and learn about the inventors who shaped wireless communication — from spark gap transmitters to WiFi 7.

Spark Gap

18871920

The first practical radio transmitters. A high-voltage spark across a gap created broadband electromagnetic pulses — noisy, inefficient, but revolutionary.

Frequency: Broadband (0.1 – 2 MHz)
Modulation: Damped oscillation (OOK)
Key Figures
Heinrich Hertz / Guglielmo Marconi

Hertz proved EM waves exist (1887). Marconi commercialised wireless telegraphy, sending signals across the Atlantic in 1901.

Spark GapDamped oscillation (OOK)
Compare with another era:

How RF Technology Evolved

  • Analog Era (1887–1980)

    From spark gaps to FM radio — engineers learned to shape continuous electromagnetic waves to carry voice, music, and television across vast distances.

  • Digital Revolution (1991–2010)

    Digital modulation unlocked encryption, error correction, and spectral efficiency. GSM, WiFi, and early LTE transformed how billions connect.

  • Modern Wireless (2019–present)

    5G NR and WiFi 7 push the boundaries with massive MIMO, beamforming, OFDMA, and multi-link operation for unprecedented speed and reliability.

Radio Time Machine