A read-only tracking-quality gauge built from real pivoted-tonearm geometry: a headshell sweeps a 215mm-pivot arm across a spinning record from lead-in to run-out while a small error needle reads the actual geometric tracking-error function, centering exactly at the two Baerwald null radii (66mm, 120mm) and drifting off zero everywhere else.
pnpm dlx shadcn@latest add "https://design.helpmarq.com/r/tonearm-skate.json"