Electrician, then developer, now industrial automation student as a side quest alongside my dev job. I write about IT/OT: sensor data you can't trust, and OT security for developers. mariusgjerd.github.iohttps://bsky.app/profile/mariusgjerd.bsky.socialhttps://bsky.app/profile/mariusgjerd.bsky.social/post/3mrkbkverac24The 4-20mA Signal: Why Your Sensor Data Still Uses 70-Year-Old Tech https://marius-newsletter-d94bcd.beehiiv.com/p/the-number-in-your-database-was-a-current-in-a-wire26 Jul 2026 11:26 +0000at://did:plc:afrc5ivrn2pr5jtorf37s4nr/app.bsky.feed.post/3mrkbkverac24