--- title: Building An LC Meter With A Franklin Oscillator | daily.dev description: A DIY LC meter built around the Franklin oscillator circuit, a historically obscure design from the 1920s Marconi era. The meter uses an Arduino to count the... canonical: https://daily.dev/posts/building-an-lc-meter-with-a-franklin-oscillator-ux9ly4iki twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Building An LC Meter With A Franklin Oscillator | daily.dev og:description: A DIY LC meter built around the Franklin oscillator circuit, a historically obscure design from the 1920s Marconi era. The meter uses an Arduino to count the... og:url: https://daily.dev/posts/building-an-lc-meter-with-a-franklin-oscillator-ux9ly4iki og:image: https://api.daily.dev/og/posts/UX9lY4iKi.png og:image:alt: Building An LC Meter With A Franklin Oscillator og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Building An LC Meter With A Franklin Oscillator **[Hackaday](https://daily.dev/sources/hackaday)** · 2 min read · 0 upvotes · 0 comments ## Summary A DIY LC meter built around the Franklin oscillator circuit, a historically obscure design from the 1920s Marconi era. The meter uses an Arduino to count the resonant frequency of an LC tank circuit, then measures the frequency shift when an unknown capacitor or inductor is added. By comparing frequency differences rather than absolute values, parasitic effects are minimized. Calibration uses a known reference capacitor, implemented either via relay or manual switch. The design achieved inductance measurements as low as 0.1 µH. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [xkcd: OH Scale](https://daily.dev/posts/xkcd-oh-scale-ybep0kzxl) · xkcd · 3 upvotes · 0 comments - [Reverse Engineering SimTower](https://daily.dev/posts/reverse-engineering-simtower-hsuy1zx6s) · Hacker News · 0 upvotes · 0 comments - [You don't need an expensive GPU to run a local LLM that actually works](https://daily.dev/posts/you-don-t-need-an-expensive-gpu-to-run-a-local-llm-that-actually-works-djjqlzkre) · XDA Developers · 0 upvotes · 0 comments --- Tags: [#iot](https://daily.dev/tags/iot) [View this post on daily.dev](https://daily.dev/posts/building-an-lc-meter-with-a-franklin-oscillator-ux9ly4iki) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Building An LC Meter With A Franklin Oscillator","url":"https://daily.dev/posts/building-an-lc-meter-with-a-franklin-oscillator-ux9ly4iki","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/building-an-lc-meter-with-a-franklin-oscillator-ux9ly4iki"},"datePublished":"2026-03-18T08:13:11.083Z","dateModified":"2026-03-18T08:13:29.860Z","description":"A DIY LC meter built around the Franklin oscillator circuit, a historically obscure design from the 1920s Marconi era. 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