Composite Video on the NES: Why's it so wobbly?

A deep technical dive into why the NES produces a wobbly composite video image. The NES PPU generates color signals directly in the composite domain using a 21.47727 MHz oscillator divided to produce 12 color phases, resulting in 227.33 colorburst cycles per scanline rather than the ideal 227.5. This creates a three-line repeating artifact pattern. Ricoh's engineers addressed this with a 'missing dot' trick — alternating scanlines between 341 and 340 dots — reducing the visible pattern to a two-frame alternation. The post also covers how games like Battletoads that disable rendering to access VRAM bypass this correction, revealing the underlying three-frame pattern.

Nguồn: https://nicole.express/2026/phase-altering-by-line.html. 8sync News chỉ tóm tắt và dẫn link; bản quyền nội dung thuộc tác giả và nguồn gốc.

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Hackaday Europe 2026: Is Your Blood Pressure Monitor Lying To You?

Digital blood pressure monitors using the oscillometric method are less accurate than commonly assumed. These $30-50 devices inflate an arm cuff and detect pressure oscillations during deflation, using fixed percentage thresholds (e.g., 40% and 80% of oscillation amplitude) to estimate systolic and diastolic values — an approximation rather than a direct measurement. Category A monitors are only required to land within ±15 mmHg for 85% of readings. To investigate this, Milos Rasic built the Open Cardiography Signal Measuring Device, an open-source platform that combines arm cuff pressure sensing with PPG, ECG, and digital stethoscope inputs to test alternative measurement algorithms and evaluate off-the-shelf monitor accuracy.

#signal-processingNguồn