A quick morning project I did to detect whether my turntable was turned on so I could automate powering on my monitors (speakers). Note - the easiest and safest way to do this was probably with an energy detecting smart plug but I didnt have enough space for one. Another advantage is that it resulst in having an esphome close to my turntable which may come in helpful for future automations. Another better alternative is probably just using a CT clamp.
- ESPHome device - I used an ESP32 DEVKIT 1
- Optocoupler
- Project box
- I also got some heatshrink