--- title: The Seemingly Impossible Oscillator | daily.dev description: A deep dive into the reverse avalanche oscillator — a circuit using a backwards-connected 2N2222 transistor, a capacitor, a resistor, and an LED, with nothing... canonical: https://daily.dev/posts/the-seemingly-impossible-oscillator-ix8szafdg twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: The Seemingly Impossible Oscillator | daily.dev og:description: A deep dive into the reverse avalanche oscillator — a circuit using a backwards-connected 2N2222 transistor, a capacitor, a resistor, and an LED, with nothing... og:url: https://daily.dev/posts/the-seemingly-impossible-oscillator-ix8szafdg og:image: https://api.daily.dev/og/posts/IX8SZAfDG.png og:image:alt: The Seemingly Impossible 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. # The Seemingly Impossible Oscillator **[Hackaday](https://daily.dev/sources/hackaday)** · 2 min read · 0 upvotes · 0 comments ## Summary A deep dive into the reverse avalanche oscillator — a circuit using a backwards-connected 2N2222 transistor, a capacitor, a resistor, and an LED, with nothing connected to the base, yet the LED flashes. The behavior is explained through avalanche breakdown: as voltage across the capacitor rises, the reverse-biased emitter-base junction eventually breaks down, discharging the capacitor in a relaxation oscillator cycle. The post explains why a transistor exhibits this behavior (due to a 'hump' in its I/V curve) while a simple diode does not, and why the emitter-base junction has a lower breakdown voltage than the collector-base junction. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Cursed circuits \#6: reverse avalanche oscillator](https://daily.dev/posts/cursed-circuits-6-reverse-avalanche-oscillator-hc2vdmwvm) · Hacker News · 0 upvotes · 0 comments - [Analog Circuitry Lets You Blow This LED Out](https://daily.dev/posts/analog-circuitry-lets-you-blow-this-led-out-avz6pro26) · Hackaday · 0 upvotes · 0 comments --- [View this post on daily.dev](https://daily.dev/posts/the-seemingly-impossible-oscillator-ix8szafdg) ```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":"The Seemingly Impossible Oscillator","url":"https://daily.dev/posts/the-seemingly-impossible-oscillator-ix8szafdg","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/the-seemingly-impossible-oscillator-ix8szafdg"},"datePublished":"2026-07-14T08:21:50.569Z","dateModified":"2026-07-14T11:44:05.796Z","description":"A deep dive into the reverse avalanche oscillator — a circuit using a backwards-connected 2N2222 transistor, a capacitor, a resistor, and an LED, with nothing...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/1943fb55f032bc5cfd3a60e6174111dc?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/1943fb55f032bc5cfd3a60e6174111dc?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Hackaday","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Hackaday","logo":"https://media.daily.dev/image/upload/s--JhDfhy70--/f_auto,q_auto/v1767541814/logos/hackaday","url":"https://daily.dev/sources/hackaday"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/the-seemingly-impossible-oscillator-ix8szafdg","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"","timeRequired":"PT2M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Hackaday","item":"https://daily.dev/sources/hackaday"},{"@type":"ListItem","position":3,"name":"The Seemingly Impossible Oscillator"}]} ```