NBTV Player

Narrow-Bandwidth Television Decoder

40×3212.5 fps

target: 12.5 fps

0:00.0--:--

Signal Waveform

PLL Lock

Signal

📼

Drop audio/video file here

WAV, MP3, OGG, FLAC, MP4, WebM

Test Patterns

Television Standard

Timing

Frame period: 80.0 ms (1/12.5)

Line period: 2.500 ms

Line rate: 400.0 Hz (32×12.5)

Pixels/line: 40

12.5 Hz Frame Sync: ✓ Standard

Sync mode: Threshold (sub-black)

Sync pulse: 120μs, Clamp: 35μs, Flywheel: ON

Sync & Signal Processing

▼

Sync Mode

Blacker-than-black pulse detection (sub-black at −0.4V)

Sync Threshold: 0.15

Brightness: 50

Contrast: 50

H.PHASE

V.PHASE

BRIGHT

CONTRAST

PLL Lost

Stopped

No Signal

Flywheel 0%

Sync Timing

Sync pulse: 120μs (~5 samples)

Clamp point: 35μs into pulse (~2 samples)

Line sync: 400 Hz (32 lines × 12.5 fps)

Frame sync: 12.5 Hz via threshold detection

Signal levels: sync=-0.4V, black=0V, white=1V

📖 How NBTV Works

▶