https://sensorrig.com/tags/calibration/Recent content in Calibration on SensorRig — Real Raspberry Pi Sensor MonitoringHugoen-usThu, 27 Aug 2026 00:00:00 +0000https://sensorrig.com/posts/ct-clamp-burden-resistor-calibration-ads1115/Thu, 27 Aug 2026 00:00:00 +0000https://sensorrig.com/posts/ct-clamp-burden-resistor-calibration-ads1115/When measuring AC current with a CT clamp (SCT013) and an ADS1115 ADC, voltage drift makes readings unreliable — a problem that surfaces repeatedly in Home Assistant communities and DIY sensor projects. This builds on my earlier whole-house energy monitor with CT clamps and an ADS1115 and uses the same asyncio collector that logs the rest of my house; the burden-resistor detail below is the one piece I left vague in that first post.https://sensorrig.com/posts/dht11-vs-dht22-honest/Fri, 07 Aug 2026 00:00:00 +0000https://sensorrig.com/posts/dht11-vs-dht22-honest/One DHT11 in my house has been logging on a one-minute interval into the same SQLite database as everything else since 25 January 2025. As of this morning that is 558 distinct days and 26,318 rows in my rollup table. A note on that table: despite being named measurements_1h it actually stores half-hour buckets — every timestamp lands on :00 or :30 — so 26,318 rows is roughly 13,160 hours, not 26,318 hours.