One of the World's Largest Free Schematic Libraries — First to Feature AI Circuit Analysis

Many thousands of schematic diagrams spanning numerous brands and manufacturers — vintage hi-fi, pro audio, consumer electronics, guitar amps, tube gear, and more. Every schematic is free to view, page by page, at full resolution. No sign-up. No PDF download. No nonsense. Sign up if you want to download the single PDF or the PDF + AI Analysis package.

🔬 Introducing AI Circuit Analysis — our master-engineer AI reads each schematic page and tells you exactly what you're looking at: signal path, stage-by-stage operation, component roles, known failure modes, repair tips, and design quirks. The kind of insight that used to live only in the heads of 40-year bench veterans. Now on every page.

Search by brand, model, or part number. Find the schematic. Understand the circuit. Fix the gear. Schems.com — built by techs, for techs.

🤖 Introducing SchemsBot — our AI assistant that knows everything in the library. Ask it anything: "What caps fail in the Accuphase A-35?"   "How do I bias a 6L6 output stage?"   "What's the difference between a 12AX7 and 12AU7?" — SchemsBot draws on thousands of schematics, AI-generated repair intelligence, tube data sheets, technical manuals, and engineering references to give you a direct, expert answer. It's like having a 40-year bench veteran on call, 24/7.

📄 AI-Analysis PDF Packets — download a professionally packaged schematic bundle: original circuit pages interleaved with AI-generated analysis, component breakdowns, repair flags, and technical notes — all in one print-ready PDF you can take straight to the bench. The schematic and the expertise, together.

Library includes: Tube Datasheet Archive — the definitive vacuum tube & valve reference • Old Tube Books and Manuals archive • NEETS (Navy Electricity & Electronics Training Series) • MIT Radiation Laboratory Series • manufacturer data sheets, application notes, and engineering classics — all searchable, all queryable via SchemsBot.