TV Sign-Off

Before 24-hour broadcasting, stations signed off every night, and these are the screens they left behind, drawn live on a canvas:

• Color Bars — the SMPTE-style pattern engineers used to calibrate color and levels, complete with the optional 1 kHz reference tone (you know the one)
• Test Card — a generic circle-and-grid card for checking geometry, focus, and gray levels; stations aired these for hours
• Static — pure analog snow; about 1% of it is actually the cosmic microwave background left over from the Big Bang, which made channel 3 surprisingly profound
• Sign-Off Sequence — the full ritual: color bars, an "END OF BROADCAST DAY" announcement, then... static until morning

Take it fullscreen for the real effect; any click or key turns the "TV" back off. The tone is synthesized with the Web Audio API. No transmitters were shut down in the making of this tool.

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